From 689cf2a5ee255f1e1f53d31bff5047d96f08290d Mon Sep 17 00:00:00 2001
From: Audrius Butkevicius <audrius.butkevicius@gmail.com>
Date: Tue, 23 Jun 2020 09:47:15 +0100
Subject: [PATCH] lib/ur: Normalise contract between syncthing and ursrv
 (#6770)

* Fix ui, hide report date

* Undo Goland madness

* UR now web scale

* Fix migration

* Fix marshaling, force tick on start

* Fix tests

* Darwin build

* Split "all" build target, add package name as a tag

* Remove pq and sql dep from syncthing, split build targets

* Empty line

* Revert "Empty line"

This reverts commit f74af2b067dadda8a343714123512bd545a643c3.

* Revert "Remove pq and sql dep from syncthing, split build targets"

This reverts commit 8fc295ad007c5bb7886c557f492dacf51be307ad.

* Revert "Split "all" build target, add package name as a tag"

This reverts commit f4dc88995106d2b06042f30bea781a0feb08e55f.

* Normalise contract types

* Fix build add more logging
---
 cmd/uraggregate/main.go                       |  52 +-
 cmd/ursrv/analytics.go                        |  17 +
 cmd/ursrv/main.go                             | 613 +-----------------
 cmd/ursrv/migration.go                        | 143 ++++
 .../syncthing/core/syncthingController.js     |  10 +-
 .../usageReportPreviewModalView.html          |   6 +-
 lib/api/api.go                                |  19 +-
 lib/api/mocked_model_test.go                  |   4 +-
 lib/model/model.go                            |  63 +-
 lib/ur/contract/contract.go                   | 425 ++++++++++++
 lib/ur/contract/contract_test.go              | 130 ++++
 lib/ur/memsize_darwin.go                      |   7 +-
 lib/ur/memsize_linux.go                       |  13 +-
 lib/ur/memsize_netbsd.go                      |  11 +-
 lib/ur/memsize_solaris.go                     |   8 +-
 lib/ur/memsize_unimpl.go                      |   6 +-
 lib/ur/memsize_windows.go                     |   8 +-
 lib/ur/usage_report.go                        | 296 ++++-----
 18 files changed, 976 insertions(+), 855 deletions(-)
 create mode 100644 cmd/ursrv/migration.go
 create mode 100644 lib/ur/contract/contract.go
 create mode 100644 lib/ur/contract/contract_test.go

diff --git a/cmd/uraggregate/main.go b/cmd/uraggregate/main.go
index f2fef605c..adcdf465e 100644
--- a/cmd/uraggregate/main.go
+++ b/cmd/uraggregate/main.go
@@ -175,13 +175,13 @@ func aggregateVersionSummary(db *sql.DB, since time.Time) (int64, error) {
 	res, err := db.Exec(`INSERT INTO VersionSummary (
 	SELECT
 		DATE_TRUNC('day', Received) AS Day,
-		SUBSTRING(Version FROM '^v\d.\d+') AS Ver,
+		SUBSTRING(Report->>'version' FROM '^v\d.\d+') AS Ver,
 		COUNT(*) AS Count
-		FROM Reports
+		FROM ReportsJson
 		WHERE
 			DATE_TRUNC('day', Received) > $1
 			AND DATE_TRUNC('day', Received) < DATE_TRUNC('day', NOW())
-			AND Version like 'v_.%'
+			AND Report->>'version' like 'v_.%'
 		GROUP BY Day, Ver
 		);
 	`, since)
@@ -195,11 +195,11 @@ func aggregateVersionSummary(db *sql.DB, since time.Time) (int64, error) {
 func aggregateUserMovement(db *sql.DB) (int64, error) {
 	rows, err := db.Query(`SELECT
 		DATE_TRUNC('day', Received) AS Day,
-		UniqueID
-		FROM Reports
+		Report->>'uniqueID'
+		FROM ReportsJson
 		WHERE
 			DATE_TRUNC('day', Received) < DATE_TRUNC('day', NOW())
-			AND Version like 'v_.%'
+			AND Report->>'version' like 'v_.%'
 		ORDER BY Day
 	`)
 	if err != nil {
@@ -276,16 +276,16 @@ func aggregatePerformance(db *sql.DB, since time.Time) (int64, error) {
 	res, err := db.Exec(`INSERT INTO Performance (
 	SELECT
 		DATE_TRUNC('day', Received) AS Day,
-		AVG(TotFiles) As TotFiles,
-		AVG(TotMiB) As TotMiB,
-		AVG(SHA256Perf) As SHA256Perf,
-		AVG(MemorySize) As MemorySize,
-		AVG(MemoryUsageMiB) As MemoryUsageMiB
-		FROM Reports
+		AVG((Report->>'totFiles')::numeric) As TotFiles,
+		AVG((Report->>'totMiB')::numeric) As TotMiB,
+		AVG((Report->>'sha256Perf')::numeric) As SHA256Perf,
+		AVG((Report->>'memorySize')::numeric) As MemorySize,
+		AVG((Report->>'memoryUsageMiB')::numeric) As MemoryUsageMiB
+		FROM ReportsJson
 		WHERE
 			DATE_TRUNC('day', Received) > $1
 			AND DATE_TRUNC('day', Received) < DATE_TRUNC('day', NOW())
-			AND Version like 'v_.%'
+			AND Report->>'version' like 'v_.%'
 		GROUP BY Day
 		);
 	`, since)
@@ -303,22 +303,22 @@ func aggregateBlockStats(db *sql.DB, since time.Time) (int64, error) {
 	SELECT
 		DATE_TRUNC('day', Received) AS Day,
 		COUNT(1) As Reports,
-		SUM(BlocksTotal) AS Total,
-		SUM(BlocksRenamed) AS Renamed,
-		SUM(BlocksReused) AS Reused,
-		SUM(BlocksPulled) AS Pulled,
-		SUM(BlocksCopyOrigin) AS CopyOrigin,
-		SUM(BlocksCopyOriginShifted) AS CopyOriginShifted,
-		SUM(BlocksCopyElsewhere) AS CopyElsewhere
-		FROM Reports
+		SUM((Report->'blockStats'->>'total')::numeric) AS Total,
+		SUM((Report->'blockStats'->>'renamed')::numeric) AS Renamed,
+		SUM((Report->'blockStats'->>'reused')::numeric) AS Reused,
+		SUM((Report->'blockStats'->>'pulled')::numeric) AS Pulled,
+		SUM((Report->'blockStats'->>'copyOrigin')::numeric) AS CopyOrigin,
+		SUM((Report->'blockStats'->>'copyOriginShifted')::numeric) AS CopyOriginShifted,
+		SUM((Report->'blockStats'->>'copyElsewhere')::numeric) AS CopyElsewhere
+		FROM ReportsJson
 		WHERE
 			DATE_TRUNC('day', Received) > $1
 			AND DATE_TRUNC('day', Received) < DATE_TRUNC('day', NOW())
-			AND ReportVersion = 3
-			AND Version like 'v_.%'
-			AND Version NOT LIKE 'v0.14.40%'
-			AND Version NOT LIKE 'v0.14.39%'
-			AND Version NOT LIKE 'v0.14.38%'
+			AND (Report->>'urVersion')::numeric >= 3
+			AND Report->>'version' like 'v_.%'
+			AND Report->>'version' NOT LIKE 'v0.14.40%'
+			AND Report->>'version' NOT LIKE 'v0.14.39%'
+			AND Report->>'version' NOT LIKE 'v0.14.38%'
 		GROUP BY Day
 	);
 	`, since)
diff --git a/cmd/ursrv/analytics.go b/cmd/ursrv/analytics.go
index d52c6c96c..0e802a06c 100644
--- a/cmd/ursrv/analytics.go
+++ b/cmd/ursrv/analytics.go
@@ -114,6 +114,23 @@ func statsForInts(data []int) [4]float64 {
 	return res
 }
 
+func statsForInt64s(data []int64) [4]float64 {
+	var res [4]float64
+	if len(data) == 0 {
+		return res
+	}
+
+	sort.Slice(data, func(a, b int) bool {
+		return data[a] < data[b]
+	})
+
+	res[0] = float64(data[int(float64(len(data))*0.05)])
+	res[1] = float64(data[len(data)/2])
+	res[2] = float64(data[int(float64(len(data))*0.95)])
+	res[3] = float64(data[len(data)-1])
+	return res
+}
+
 func statsForFloats(data []float64) [4]float64 {
 	var res [4]float64
 	if len(data) == 0 {
diff --git a/cmd/ursrv/main.go b/cmd/ursrv/main.go
index 6a6a99be8..c7c16b583 100644
--- a/cmd/ursrv/main.go
+++ b/cmd/ursrv/main.go
@@ -10,10 +10,7 @@ import (
 	"bytes"
 	"crypto/tls"
 	"database/sql"
-	"database/sql/driver"
 	"encoding/json"
-	"errors"
-	"fmt"
 	"html/template"
 	"io"
 	"io/ioutil"
@@ -29,8 +26,9 @@ import (
 	"time"
 	"unicode"
 
-	"github.com/lib/pq"
-	geoip2 "github.com/oschwald/geoip2-golang"
+	"github.com/oschwald/geoip2-golang"
+
+	"github.com/syncthing/syncthing/lib/ur/contract"
 )
 
 var (
@@ -103,585 +101,44 @@ func getEnvDefault(key, def string) string {
 	return def
 }
 
-type IntMap map[string]int
-
-func (p IntMap) Value() (driver.Value, error) {
-	return json.Marshal(p)
-}
-
-func (p *IntMap) Scan(src interface{}) error {
-	source, ok := src.([]byte)
-	if !ok {
-		return errors.New("Type assertion .([]byte) failed.")
-	}
-
-	var i map[string]int
-	err := json.Unmarshal(source, &i)
-	if err != nil {
-		return err
-	}
-
-	*p = i
-	return nil
-}
-
-type report struct {
-	Received time.Time // Only from DB
-
-	UniqueID       string
-	Version        string
-	LongVersion    string
-	Platform       string
-	NumFolders     int
-	NumDevices     int
-	TotFiles       int
-	FolderMaxFiles int
-	TotMiB         int
-	FolderMaxMiB   int
-	MemoryUsageMiB int
-	SHA256Perf     float64
-	MemorySize     int
-
-	// v2 fields
-
-	URVersion  int
-	NumCPU     int
-	FolderUses struct {
-		SendOnly            int
-		ReceiveOnly         int
-		IgnorePerms         int
-		IgnoreDelete        int
-		AutoNormalize       int
-		SimpleVersioning    int
-		ExternalVersioning  int
-		StaggeredVersioning int
-		TrashcanVersioning  int
-	}
-	DeviceUses struct {
-		Introducer       int
-		CustomCertName   int
-		CompressAlways   int
-		CompressMetadata int
-		CompressNever    int
-		DynamicAddr      int
-		StaticAddr       int
-	}
-	Announce struct {
-		GlobalEnabled     bool
-		LocalEnabled      bool
-		DefaultServersDNS int
-		DefaultServersIP  int
-		OtherServers      int
-	}
-	Relays struct {
-		Enabled        bool
-		DefaultServers int
-		OtherServers   int
-	}
-	UsesRateLimit        bool
-	UpgradeAllowedManual bool
-	UpgradeAllowedAuto   bool
-
-	// V2.5 fields (fields that were in v2 but never added to the database
-	UpgradeAllowedPre bool
-	RescanIntvs       pq.Int64Array
-
-	// v3 fields
-
-	Uptime                     int
-	NATType                    string
-	AlwaysLocalNets            bool
-	CacheIgnoredFiles          bool
-	OverwriteRemoteDeviceNames bool
-	ProgressEmitterEnabled     bool
-	CustomDefaultFolderPath    bool
-	WeakHashSelection          string
-	CustomTrafficClass         bool
-	CustomTempIndexMinBlocks   bool
-	TemporariesDisabled        bool
-	TemporariesCustom          bool
-	LimitBandwidthInLan        bool
-	CustomReleaseURL           bool
-	RestartOnWakeup            bool
-	CustomStunServers          bool
-
-	FolderUsesV3 struct {
-		ScanProgressDisabled    int
-		ConflictsDisabled       int
-		ConflictsUnlimited      int
-		ConflictsOther          int
-		DisableSparseFiles      int
-		DisableTempIndexes      int
-		AlwaysWeakHash          int
-		CustomWeakHashThreshold int
-		FsWatcherEnabled        int
-		PullOrder               IntMap
-		FilesystemType          IntMap
-		FsWatcherDelays         pq.Int64Array
-	}
-
-	GUIStats struct {
-		Enabled                   int
-		UseTLS                    int
-		UseAuth                   int
-		InsecureAdminAccess       int
-		Debugging                 int
-		InsecureSkipHostCheck     int
-		InsecureAllowFrameLoading int
-		ListenLocal               int
-		ListenUnspecified         int
-		Theme                     IntMap
-	}
-
-	BlockStats struct {
-		Total             int
-		Renamed           int
-		Reused            int
-		Pulled            int
-		CopyOrigin        int
-		CopyOriginShifted int
-		CopyElsewhere     int
-	}
-
-	TransportStats IntMap
-
-	IgnoreStats struct {
-		Lines           int
-		Inverts         int
-		Folded          int
-		Deletable       int
-		Rooted          int
-		Includes        int
-		EscapedIncludes int
-		DoubleStars     int
-		Stars           int
-	}
-
-	// V3 fields added late in the RC
-	WeakHashEnabled bool
-
-	// Generated
-
-	Date    string
-	Address string
-}
-
-func (r *report) Validate() error {
-	if r.UniqueID == "" || r.Version == "" || r.Platform == "" {
-		return errors.New("missing required field")
-	}
-	if len(r.Date) != 8 {
-		return errors.New("date not initialized")
-	}
-
-	// Some fields may not be null.
-	if r.RescanIntvs == nil {
-		r.RescanIntvs = []int64{}
-	}
-	if r.FolderUsesV3.FsWatcherDelays == nil {
-		r.FolderUsesV3.FsWatcherDelays = []int64{}
-	}
-
-	return nil
-}
-
-func (r *report) FieldPointers() []interface{} {
-	// All the fields of the report, in the same order as the database fields.
-	return []interface{}{
-		&r.Received, &r.UniqueID, &r.Version, &r.LongVersion, &r.Platform,
-		&r.NumFolders, &r.NumDevices, &r.TotFiles, &r.FolderMaxFiles,
-		&r.TotMiB, &r.FolderMaxMiB, &r.MemoryUsageMiB, &r.SHA256Perf,
-		&r.MemorySize, &r.Date,
-		// V2
-		&r.URVersion, &r.NumCPU, &r.FolderUses.SendOnly, &r.FolderUses.IgnorePerms,
-		&r.FolderUses.IgnoreDelete, &r.FolderUses.AutoNormalize, &r.DeviceUses.Introducer,
-		&r.DeviceUses.CustomCertName, &r.DeviceUses.CompressAlways,
-		&r.DeviceUses.CompressMetadata, &r.DeviceUses.CompressNever,
-		&r.DeviceUses.DynamicAddr, &r.DeviceUses.StaticAddr,
-		&r.Announce.GlobalEnabled, &r.Announce.LocalEnabled,
-		&r.Announce.DefaultServersDNS, &r.Announce.DefaultServersIP,
-		&r.Announce.OtherServers, &r.Relays.Enabled, &r.Relays.DefaultServers,
-		&r.Relays.OtherServers, &r.UsesRateLimit, &r.UpgradeAllowedManual,
-		&r.UpgradeAllowedAuto, &r.FolderUses.SimpleVersioning,
-		&r.FolderUses.ExternalVersioning, &r.FolderUses.StaggeredVersioning,
-		&r.FolderUses.TrashcanVersioning,
-
-		// V2.5
-		&r.UpgradeAllowedPre, &r.RescanIntvs,
-
-		// V3
-		&r.Uptime, &r.NATType, &r.AlwaysLocalNets, &r.CacheIgnoredFiles,
-		&r.OverwriteRemoteDeviceNames, &r.ProgressEmitterEnabled, &r.CustomDefaultFolderPath,
-		&r.WeakHashSelection, &r.CustomTrafficClass, &r.CustomTempIndexMinBlocks,
-		&r.TemporariesDisabled, &r.TemporariesCustom, &r.LimitBandwidthInLan,
-		&r.CustomReleaseURL, &r.RestartOnWakeup, &r.CustomStunServers,
-
-		&r.FolderUsesV3.ScanProgressDisabled, &r.FolderUsesV3.ConflictsDisabled,
-		&r.FolderUsesV3.ConflictsUnlimited, &r.FolderUsesV3.ConflictsOther,
-		&r.FolderUsesV3.DisableSparseFiles, &r.FolderUsesV3.DisableTempIndexes,
-		&r.FolderUsesV3.AlwaysWeakHash, &r.FolderUsesV3.CustomWeakHashThreshold,
-		&r.FolderUsesV3.FsWatcherEnabled,
-
-		&r.FolderUsesV3.PullOrder, &r.FolderUsesV3.FilesystemType,
-		&r.FolderUsesV3.FsWatcherDelays,
-
-		&r.GUIStats.Enabled, &r.GUIStats.UseTLS, &r.GUIStats.UseAuth,
-		&r.GUIStats.InsecureAdminAccess,
-		&r.GUIStats.Debugging, &r.GUIStats.InsecureSkipHostCheck,
-		&r.GUIStats.InsecureAllowFrameLoading, &r.GUIStats.ListenLocal,
-		&r.GUIStats.ListenUnspecified, &r.GUIStats.Theme,
-
-		&r.BlockStats.Total, &r.BlockStats.Renamed,
-		&r.BlockStats.Reused, &r.BlockStats.Pulled, &r.BlockStats.CopyOrigin,
-		&r.BlockStats.CopyOriginShifted, &r.BlockStats.CopyElsewhere,
-
-		&r.TransportStats,
-
-		&r.IgnoreStats.Lines, &r.IgnoreStats.Inverts, &r.IgnoreStats.Folded,
-		&r.IgnoreStats.Deletable, &r.IgnoreStats.Rooted, &r.IgnoreStats.Includes,
-		&r.IgnoreStats.EscapedIncludes, &r.IgnoreStats.DoubleStars, &r.IgnoreStats.Stars,
-
-		// V3 added late in the RC
-		&r.WeakHashEnabled,
-		&r.Address,
-
-		// Receive only folders
-		&r.FolderUses.ReceiveOnly,
-	}
-}
-
-func (r *report) FieldNames() []string {
-	// The database fields that back this struct in PostgreSQL
-	return []string{
-		// V1
-		"Received",
-		"UniqueID",
-		"Version",
-		"LongVersion",
-		"Platform",
-		"NumFolders",
-		"NumDevices",
-		"TotFiles",
-		"FolderMaxFiles",
-		"TotMiB",
-		"FolderMaxMiB",
-		"MemoryUsageMiB",
-		"SHA256Perf",
-		"MemorySize",
-		"Date",
-		// V2
-		"ReportVersion",
-		"NumCPU",
-		"FolderRO",
-		"FolderIgnorePerms",
-		"FolderIgnoreDelete",
-		"FolderAutoNormalize",
-		"DeviceIntroducer",
-		"DeviceCustomCertName",
-		"DeviceCompressAlways",
-		"DeviceCompressMetadata",
-		"DeviceCompressNever",
-		"DeviceDynamicAddr",
-		"DeviceStaticAddr",
-		"AnnounceGlobalEnabled",
-		"AnnounceLocalEnabled",
-		"AnnounceDefaultServersDNS",
-		"AnnounceDefaultServersIP",
-		"AnnounceOtherServers",
-		"RelayEnabled",
-		"RelayDefaultServers",
-		"RelayOtherServers",
-		"RateLimitEnabled",
-		"UpgradeAllowedManual",
-		"UpgradeAllowedAuto",
-		// v0.12.19+
-		"FolderSimpleVersioning",
-		"FolderExternalVersioning",
-		"FolderStaggeredVersioning",
-		"FolderTrashcanVersioning",
-		// V2.5
-		"UpgradeAllowedPre",
-		"RescanIntvs",
-		// V3
-		"Uptime",
-		"NATType",
-		"AlwaysLocalNets",
-		"CacheIgnoredFiles",
-		"OverwriteRemoteDeviceNames",
-		"ProgressEmitterEnabled",
-		"CustomDefaultFolderPath",
-		"WeakHashSelection",
-		"CustomTrafficClass",
-		"CustomTempIndexMinBlocks",
-		"TemporariesDisabled",
-		"TemporariesCustom",
-		"LimitBandwidthInLan",
-		"CustomReleaseURL",
-		"RestartOnWakeup",
-		"CustomStunServers",
-
-		"FolderScanProgressDisabled",
-		"FolderConflictsDisabled",
-		"FolderConflictsUnlimited",
-		"FolderConflictsOther",
-		"FolderDisableSparseFiles",
-		"FolderDisableTempIndexes",
-		"FolderAlwaysWeakHash",
-		"FolderCustomWeakHashThreshold",
-		"FolderFsWatcherEnabled",
-		"FolderPullOrder",
-		"FolderFilesystemType",
-		"FolderFsWatcherDelays",
-
-		"GUIEnabled",
-		"GUIUseTLS",
-		"GUIUseAuth",
-		"GUIInsecureAdminAccess",
-		"GUIDebugging",
-		"GUIInsecureSkipHostCheck",
-		"GUIInsecureAllowFrameLoading",
-		"GUIListenLocal",
-		"GUIListenUnspecified",
-		"GUITheme",
-
-		"BlocksTotal",
-		"BlocksRenamed",
-		"BlocksReused",
-		"BlocksPulled",
-		"BlocksCopyOrigin",
-		"BlocksCopyOriginShifted",
-		"BlocksCopyElsewhere",
-
-		"Transport",
-
-		"IgnoreLines",
-		"IgnoreInverts",
-		"IgnoreFolded",
-		"IgnoreDeletable",
-		"IgnoreRooted",
-		"IgnoreIncludes",
-		"IgnoreEscapedIncludes",
-		"IgnoreDoubleStars",
-		"IgnoreStars",
-
-		// V3 added late in the RC
-		"WeakHashEnabled",
-		"Address",
-
-		// Receive only folders
-		"FolderRecvOnly",
-	}
-}
-
 func setupDB(db *sql.DB) error {
-	_, err := db.Exec(`CREATE TABLE IF NOT EXISTS Reports (
+	_, err := db.Exec(`CREATE TABLE IF NOT EXISTS ReportsJson (
 		Received TIMESTAMP NOT NULL,
-		UniqueID VARCHAR(32) NOT NULL,
-		Version VARCHAR(32) NOT NULL,
-		LongVersion VARCHAR(256) NOT NULL,
-		Platform VARCHAR(32) NOT NULL,
-		NumFolders INTEGER NOT NULL,
-		NumDevices INTEGER NOT NULL,
-		TotFiles INTEGER NOT NULL,
-		FolderMaxFiles INTEGER NOT NULL,
-		TotMiB INTEGER NOT NULL,
-		FolderMaxMiB INTEGER NOT NULL,
-		MemoryUsageMiB INTEGER NOT NULL,
-		SHA256Perf DOUBLE PRECISION NOT NULL,
-		MemorySize INTEGER NOT NULL,
-		Date VARCHAR(8) NOT NULL
+		Report JSONB NOT NULL
 	)`)
 	if err != nil {
 		return err
 	}
 
 	var t string
-	row := db.QueryRow(`SELECT 'UniqueIDIndex'::regclass`)
-	if err := row.Scan(&t); err != nil {
-		if _, err = db.Exec(`CREATE UNIQUE INDEX UniqueIDIndex ON Reports (Date, UniqueID)`); err != nil {
+	if err := db.QueryRow(`SELECT 'UniqueIDJsonIndex'::regclass`).Scan(&t); err != nil {
+		if _, err = db.Exec(`CREATE UNIQUE INDEX UniqueIDJsonIndex ON ReportsJson ((Report->>'date'), (Report->>'uniqueID'))`); err != nil {
 			return err
 		}
 	}
 
-	row = db.QueryRow(`SELECT 'ReceivedIndex'::regclass`)
-	if err := row.Scan(&t); err != nil {
-		if _, err = db.Exec(`CREATE INDEX ReceivedIndex ON Reports (Received)`); err != nil {
+	if err := db.QueryRow(`SELECT 'ReceivedJsonIndex'::regclass`).Scan(&t); err != nil {
+		if _, err = db.Exec(`CREATE INDEX ReceivedJsonIndex ON ReportsJson (Received)`); err != nil {
 			return err
 		}
 	}
 
-	// V2
-
-	row = db.QueryRow(`SELECT attname FROM pg_attribute WHERE attrelid = (SELECT oid FROM pg_class WHERE relname = 'reports') AND attname = 'reportversion'`)
-	if err := row.Scan(&t); err != nil {
-		// The ReportVersion column doesn't exist; add the new columns.
-		_, err = db.Exec(`ALTER TABLE Reports
-		ADD COLUMN ReportVersion INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN NumCPU INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderRO  INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderIgnorePerms INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderIgnoreDelete INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderAutoNormalize INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN DeviceIntroducer INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN DeviceCustomCertName INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN DeviceCompressAlways INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN DeviceCompressMetadata INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN DeviceCompressNever INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN DeviceDynamicAddr INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN DeviceStaticAddr INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN AnnounceGlobalEnabled BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN AnnounceLocalEnabled BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN AnnounceDefaultServersDNS INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN AnnounceDefaultServersIP INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN AnnounceOtherServers INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN RelayEnabled BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN RelayDefaultServers INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN RelayOtherServers INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN RateLimitEnabled BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN UpgradeAllowedManual BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN UpgradeAllowedAuto BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN FolderSimpleVersioning INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderExternalVersioning INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderStaggeredVersioning INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderTrashcanVersioning INTEGER NOT NULL DEFAULT 0
-		`)
-		if err != nil {
+	if err := db.QueryRow(`SELECT 'ReportVersionJsonIndex'::regclass`).Scan(&t); err != nil {
+		if _, err = db.Exec(`CREATE INDEX ReportVersionJsonIndex ON ReportsJson (cast((Report->>'urVersion') as numeric))`); err != nil {
 			return err
 		}
 	}
 
-	row = db.QueryRow(`SELECT 'ReportVersionIndex'::regclass`)
-	if err := row.Scan(&t); err != nil {
-		if _, err = db.Exec(`CREATE INDEX ReportVersionIndex ON Reports (ReportVersion)`); err != nil {
-			return err
-		}
-	}
-
-	// V2.5
-
-	row = db.QueryRow(`SELECT attname FROM pg_attribute WHERE attrelid = (SELECT oid FROM pg_class WHERE relname = 'reports') AND attname = 'upgradeallowedpre'`)
-	if err := row.Scan(&t); err != nil {
-		// The ReportVersion column doesn't exist; add the new columns.
-		_, err = db.Exec(`ALTER TABLE Reports
-		ADD COLUMN UpgradeAllowedPre BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN RescanIntvs INT[] NOT NULL DEFAULT '{}'
-		`)
-		if err != nil {
-			return err
-		}
-	}
-
-	// V3
-
-	row = db.QueryRow(`SELECT attname FROM pg_attribute WHERE attrelid = (SELECT oid FROM pg_class WHERE relname = 'reports') AND attname = 'uptime'`)
-	if err := row.Scan(&t); err != nil {
-		// The Uptime column doesn't exist; add the new columns.
-		_, err = db.Exec(`ALTER TABLE Reports
-		ADD COLUMN Uptime INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN NATType VARCHAR(32) NOT NULL DEFAULT '',
-		ADD COLUMN AlwaysLocalNets BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN CacheIgnoredFiles BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN OverwriteRemoteDeviceNames BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN ProgressEmitterEnabled BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN CustomDefaultFolderPath BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN WeakHashSelection VARCHAR(32) NOT NULL DEFAULT '',
-		ADD COLUMN CustomTrafficClass BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN CustomTempIndexMinBlocks BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN TemporariesDisabled BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN TemporariesCustom BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN LimitBandwidthInLan BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN CustomReleaseURL BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN RestartOnWakeup BOOLEAN NOT NULL DEFAULT FALSE,
-		ADD COLUMN CustomStunServers BOOLEAN NOT NULL DEFAULT FALSE,
-
-		ADD COLUMN FolderScanProgressDisabled INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderConflictsDisabled INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderConflictsUnlimited INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderConflictsOther INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderDisableSparseFiles INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderDisableTempIndexes INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderAlwaysWeakHash INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderCustomWeakHashThreshold INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderFsWatcherEnabled INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN FolderPullOrder JSONB NOT NULL DEFAULT '{}',
-		ADD COLUMN FolderFilesystemType JSONB NOT NULL DEFAULT '{}',
-		ADD COLUMN FolderFsWatcherDelays INT[] NOT NULL DEFAULT '{}',
-
-		ADD COLUMN GUIEnabled INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN GUIUseTLS INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN GUIUseAuth INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN GUIInsecureAdminAccess INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN GUIDebugging INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN GUIInsecureSkipHostCheck INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN GUIInsecureAllowFrameLoading INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN GUIListenLocal INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN GUIListenUnspecified INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN GUITheme JSONB NOT NULL DEFAULT '{}',
-
-		ADD COLUMN BlocksTotal INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN BlocksRenamed INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN BlocksReused INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN BlocksPulled INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN BlocksCopyOrigin INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN BlocksCopyOriginShifted INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN BlocksCopyElsewhere INTEGER NOT NULL DEFAULT 0,
-
-		ADD COLUMN Transport JSONB NOT NULL DEFAULT '{}',
-
-		ADD COLUMN IgnoreLines INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN IgnoreInverts INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN IgnoreFolded INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN IgnoreDeletable INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN IgnoreRooted INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN IgnoreIncludes INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN IgnoreEscapedIncludes INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN IgnoreDoubleStars INTEGER NOT NULL DEFAULT 0,
-		ADD COLUMN IgnoreStars INTEGER NOT NULL DEFAULT 0
-		`)
-		if err != nil {
-			return err
-		}
-	}
-
-	// V3 added late in the RC
-
-	row = db.QueryRow(`SELECT attname FROM pg_attribute WHERE attrelid = (SELECT oid FROM pg_class WHERE relname = 'reports') AND attname = 'weakhashenabled'`)
-	if err := row.Scan(&t); err != nil {
-		// The WeakHashEnabled column doesn't exist; add the new columns.
-		_, err = db.Exec(`ALTER TABLE Reports
-		ADD COLUMN WeakHashEnabled BOOLEAN NOT NULL DEFAULT FALSE
-		ADD COLUMN Address VARCHAR(45) NOT NULL DEFAULT ''
-		`)
-		if err != nil {
-			return err
-		}
-	}
-
-	// Receive only added ad-hoc
-
-	row = db.QueryRow(`SELECT attname FROM pg_attribute WHERE attrelid = (SELECT oid FROM pg_class WHERE relname = 'reports') AND attname = 'folderrecvonly'`)
-	if err := row.Scan(&t); err != nil {
-		// The RecvOnly column doesn't exist; add it.
-		_, err = db.Exec(`ALTER TABLE Reports
-		ADD COLUMN FolderRecvOnly INTEGER NOT NULL DEFAULT 0
-		`)
-		if err != nil {
-			return err
-		}
+	// Migrate from old schema to new schema if the table exists.
+	if err := migrate(db); err != nil {
+		return err
 	}
 
 	return nil
 }
 
-func insertReport(db *sql.DB, r report) error {
-	r.Received = time.Now().UTC()
-	fields := r.FieldPointers()
-	params := make([]string, len(fields))
-	for i := range params {
-		params[i] = fmt.Sprintf("$%d", i+1)
-	}
-	query := "INSERT INTO Reports (" + strings.Join(r.FieldNames(), ", ") + ") VALUES (" + strings.Join(params, ", ") + ")"
-	_, err := db.Exec(query, fields...)
+func insertReport(db *sql.DB, r contract.Report) error {
+	_, err := db.Exec("INSERT INTO ReportsJson (Report, Received) VALUES ($1, $2)", r, time.Now().UTC())
 
 	return err
 }
@@ -689,9 +146,9 @@ func insertReport(db *sql.DB, r report) error {
 type withDBFunc func(*sql.DB, http.ResponseWriter, *http.Request)
 
 func withDB(db *sql.DB, f withDBFunc) http.HandlerFunc {
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+	return func(w http.ResponseWriter, r *http.Request) {
 		f(db, w, r)
-	})
+	}
 }
 
 func main() {
@@ -778,7 +235,7 @@ const maxCacheTime = 15 * time.Minute
 func cacheRefresher(db *sql.DB) {
 	ticker := time.NewTicker(maxCacheTime - time.Minute)
 	defer ticker.Stop()
-	for range ticker.C {
+	for ; true; <-ticker.C {
 		cacheMut.Lock()
 		if err := refreshCacheLocked(db); err != nil {
 			log.Println(err)
@@ -861,7 +318,7 @@ func newDataHandler(db *sql.DB, w http.ResponseWriter, r *http.Request) {
 		addr = ""
 	}
 
-	var rep report
+	var rep contract.Report
 	rep.Date = time.Now().UTC().Format("20060102")
 	rep.Address = addr
 
@@ -1069,11 +526,11 @@ func getReport(db *sql.DB) map[string]interface{} {
 	var numDevices []int
 	var totFiles []int
 	var maxFiles []int
-	var totMiB []int
-	var maxMiB []int
-	var memoryUsage []int
+	var totMiB []int64
+	var maxMiB []int64
+	var memoryUsage []int64
 	var sha256Perf []float64
-	var memorySize []int
+	var memorySize []int64
 	var uptime []int
 	var compilers []string
 	var builders []string
@@ -1112,9 +569,9 @@ func getReport(db *sql.DB) map[string]interface{} {
 
 	var numCPU []int
 
-	var rep report
+	var rep contract.Report
 
-	rows, err := db.Query(`SELECT ` + strings.Join(rep.FieldNames(), ",") + ` FROM Reports WHERE Received > now() - '1 day'::INTERVAL`)
+	rows, err := db.Query(`SELECT Received, Report FROM ReportsJson WHERE Received > now() - '1 day'::INTERVAL`)
 	if err != nil {
 		log.Println("sql:", err)
 		return nil
@@ -1122,7 +579,7 @@ func getReport(db *sql.DB) map[string]interface{} {
 	defer rows.Close()
 
 	for rows.Next() {
-		err := rows.Scan(rep.FieldPointers()...)
+		err := rows.Scan(&rep.Received, &rep)
 
 		if err != nil {
 			log.Println("sql:", err)
@@ -1173,19 +630,19 @@ func getReport(db *sql.DB) map[string]interface{} {
 			maxFiles = append(maxFiles, rep.FolderMaxFiles)
 		}
 		if rep.TotMiB > 0 {
-			totMiB = append(totMiB, rep.TotMiB*(1<<20))
+			totMiB = append(totMiB, int64(rep.TotMiB)*(1<<20))
 		}
 		if rep.FolderMaxMiB > 0 {
-			maxMiB = append(maxMiB, rep.FolderMaxMiB*(1<<20))
+			maxMiB = append(maxMiB, int64(rep.FolderMaxMiB)*(1<<20))
 		}
 		if rep.MemoryUsageMiB > 0 {
-			memoryUsage = append(memoryUsage, rep.MemoryUsageMiB*(1<<20))
+			memoryUsage = append(memoryUsage, int64(rep.MemoryUsageMiB)*(1<<20))
 		}
 		if rep.SHA256Perf > 0 {
 			sha256Perf = append(sha256Perf, rep.SHA256Perf*(1<<20))
 		}
 		if rep.MemorySize > 0 {
-			memorySize = append(memorySize, rep.MemorySize*(1<<20))
+			memorySize = append(memorySize, int64(rep.MemorySize)*(1<<20))
 		}
 		if rep.Uptime > 0 {
 			uptime = append(uptime, rep.Uptime)
@@ -1336,14 +793,14 @@ func getReport(db *sql.DB) map[string]interface{} {
 	})
 
 	categories = append(categories, category{
-		Values: statsForInts(totMiB),
+		Values: statsForInt64s(totMiB),
 		Descr:  "Data Managed per Device",
 		Unit:   "B",
 		Type:   NumberBinary,
 	})
 
 	categories = append(categories, category{
-		Values: statsForInts(maxMiB),
+		Values: statsForInt64s(maxMiB),
 		Descr:  "Data in Largest Folder",
 		Unit:   "B",
 		Type:   NumberBinary,
@@ -1360,14 +817,14 @@ func getReport(db *sql.DB) map[string]interface{} {
 	})
 
 	categories = append(categories, category{
-		Values: statsForInts(memoryUsage),
+		Values: statsForInt64s(memoryUsage),
 		Descr:  "Memory Usage",
 		Unit:   "B",
 		Type:   NumberBinary,
 	})
 
 	categories = append(categories, category{
-		Values: statsForInts(memorySize),
+		Values: statsForInt64s(memorySize),
 		Descr:  "System Memory",
 		Unit:   "B",
 		Type:   NumberBinary,
diff --git a/cmd/ursrv/migration.go b/cmd/ursrv/migration.go
new file mode 100644
index 000000000..9b92d6ef3
--- /dev/null
+++ b/cmd/ursrv/migration.go
@@ -0,0 +1,143 @@
+// Copyright (C) 2020 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"database/sql"
+	"database/sql/driver"
+	"encoding/json"
+	"errors"
+	"log"
+	"strings"
+
+	"github.com/lib/pq"
+
+	"github.com/syncthing/syncthing/lib/ur/contract"
+)
+
+func migrate(db *sql.DB) error {
+	var count uint64
+	log.Println("Checking old table row count, this might take a while...")
+	if err := db.QueryRow(`SELECT COUNT(1) FROM Reports`).Scan(&count); err != nil || count == 0 {
+		// err != nil most likely means table does not exist.
+		return nil
+	}
+	log.Printf("Found %d records, will perform migration.", count)
+
+	tx, err := db.Begin()
+	if err != nil {
+		log.Println("sql:", err)
+		return err
+	}
+	defer tx.Rollback()
+
+	// These must be lower case, because we don't quote them when creating, so postgres creates them lower case.
+	// Yet pg.CopyIn quotes them, which makes them case sensitive.
+	stmt, err := tx.Prepare(pq.CopyIn("reportsjson", "received", "report"))
+	if err != nil {
+		log.Println("sql:", err)
+		return err
+	}
+
+	// Custom types used in the old struct.
+	var rep contract.Report
+	var rescanIntvs pq.Int64Array
+	var fsWatcherDelay pq.Int64Array
+	pullOrder := make(IntMap)
+	fileSystemType := make(IntMap)
+	themes := make(IntMap)
+	transportStats := make(IntMap)
+
+	rows, err := db.Query(`SELECT ` + strings.Join(rep.FieldNames(), ", ") + `, FolderFsWatcherDelays, RescanIntvs, FolderPullOrder, FolderFilesystemType, GUITheme, Transport FROM Reports`)
+	if err != nil {
+		log.Println("sql:", err)
+		return err
+	}
+	defer rows.Close()
+
+	var done uint64
+	pct := count / 100
+
+	for rows.Next() {
+		err := rows.Scan(append(rep.FieldPointers(), &fsWatcherDelay, &rescanIntvs, &pullOrder, &fileSystemType, &themes, &transportStats)...)
+		if err != nil {
+			log.Println("sql scan:", err)
+			return err
+		}
+		// Patch up parts that used to use custom types
+		rep.RescanIntvs = make([]int, len(rescanIntvs))
+		for i := range rescanIntvs {
+			rep.RescanIntvs[i] = int(rescanIntvs[i])
+		}
+		rep.FolderUsesV3.FsWatcherDelays = make([]int, len(fsWatcherDelay))
+		for i := range fsWatcherDelay {
+			rep.FolderUsesV3.FsWatcherDelays[i] = int(fsWatcherDelay[i])
+		}
+		rep.FolderUsesV3.PullOrder = pullOrder
+		rep.FolderUsesV3.FilesystemType = fileSystemType
+		rep.GUIStats.Theme = themes
+		rep.TransportStats = transportStats
+
+		_, err = stmt.Exec(rep.Received, rep)
+		if err != nil {
+			log.Println("sql insert:", err)
+			return err
+		}
+		done++
+		if done%pct == 0 {
+			log.Printf("Migration progress %d/%d (%d%%)", done, count, (100*done)/count)
+		}
+	}
+
+	// Tell the driver bulk copy is finished
+	_, err = stmt.Exec()
+	if err != nil {
+		log.Println("sql stmt exec:", err)
+		return err
+	}
+
+	err = stmt.Close()
+	if err != nil {
+		log.Println("sql stmt close:", err)
+		return err
+	}
+
+	_, err = tx.Exec("DROP TABLE Reports")
+	if err != nil {
+		log.Println("sql drop:", err)
+		return err
+	}
+
+	err = tx.Commit()
+	if err != nil {
+		log.Println("sql commit:", err)
+		return err
+	}
+	return nil
+}
+
+type IntMap map[string]int
+
+func (p IntMap) Value() (driver.Value, error) {
+	return json.Marshal(p)
+}
+
+func (p *IntMap) Scan(src interface{}) error {
+	source, ok := src.([]byte)
+	if !ok {
+		return errors.New("Type assertion .([]byte) failed.")
+	}
+
+	var i map[string]int
+	err := json.Unmarshal(source, &i)
+	if err != nil {
+		return err
+	}
+
+	*p = i
+	return nil
+}
diff --git a/gui/default/syncthing/core/syncthingController.js b/gui/default/syncthing/core/syncthingController.js
index 7d92be1a2..161dd7fdd 100755
--- a/gui/default/syncthing/core/syncthingController.js
+++ b/gui/default/syncthing/core/syncthingController.js
@@ -32,8 +32,6 @@ angular.module('syncthing.core')
         $scope.protocolChanged = false;
         $scope.reportData = {};
         $scope.reportDataPreview = '';
-        $scope.reportDataPreviewVersion = '';
-        $scope.reportDataPreviewDiff = false;
         $scope.reportPreview = false;
         $scope.folders = {};
         $scope.seenError = '';
@@ -2322,13 +2320,13 @@ angular.module('syncthing.core')
             $scope.reportPreview = true;
         };
 
-        $scope.refreshReportDataPreview = function () {
+        $scope.refreshReportDataPreview = function (ver, diff) {
             $scope.reportDataPreview = '';
-            if (!$scope.reportDataPreviewVersion) {
+            if (!ver) {
                 return;
             }
-            var version = parseInt($scope.reportDataPreviewVersion);
-            if ($scope.reportDataPreviewDiff && version > 2) {
+            var version = parseInt(ver);
+            if (diff && version > 2) {
                 $q.all([
                     $http.get(urlbase + '/svc/report?version=' + version),
                     $http.get(urlbase + '/svc/report?version=' + (version - 1)),
diff --git a/gui/default/syncthing/usagereport/usageReportPreviewModalView.html b/gui/default/syncthing/usagereport/usageReportPreviewModalView.html
index 95d5ef156..1064be349 100644
--- a/gui/default/syncthing/usagereport/usageReportPreviewModalView.html
+++ b/gui/default/syncthing/usagereport/usageReportPreviewModalView.html
@@ -6,13 +6,13 @@
     <p translate>The aggregated statistics are publicly available at the URL below.</p>
     <p><a href="https://data.syncthing.net/" target="_blank">https://data.syncthing.net/</a></p>
     <label translate>Version</label>
-    <select id="urPreviewVersion" class="form-control" ng-model="$parent.$parent.reportDataPreviewVersion" ng-change="refreshReportDataPreview()">
+    <select id="urPreviewVersion" class="form-control" ng-model="reportDataPreviewVersion" ng-change="refreshReportDataPreview(reportDataPreviewVersion, reportDataPreviewDiff)">
       <option selected value translate>Select a version</option>
       <option ng-repeat="n in urVersions()" value="{{n}}">{{'Version' | translate}} {{n}}</option>
     </select>
-    <div class="checkbox" ng-if="$parent.$parent.reportDataPreviewVersion > 2">
+    <div class="checkbox" ng-if="reportDataPreviewVersion > 2">
       <label>
-        <input type="checkbox" ng-model="$parent.$parent.$parent.reportDataPreviewDiff" ng-change="refreshReportDataPreview()" />
+        <input type="checkbox" ng-model="reportDataPreviewDiff" ng-change="refreshReportDataPreview(reportDataPreviewVersion, reportDataPreviewDiff)" />
         <span translate>Show diff with previous version</span>
       </label>
     </div>
diff --git a/lib/api/api.go b/lib/api/api.go
index 279e7a56b..bcd1ca693 100644
--- a/lib/api/api.go
+++ b/lib/api/api.go
@@ -1063,10 +1063,15 @@ func (s *service) getSupportBundle(w http.ResponseWriter, r *http.Request) {
 	}
 
 	// Report Data as a JSON
-	if usageReportingData, err := json.MarshalIndent(s.urService.ReportData(context.TODO()), "", "  "); err != nil {
-		l.Warnln("Support bundle: failed to create versionPlatform.json:", err)
+	if r, err := s.urService.ReportData(context.TODO()); err != nil {
+		l.Warnln("Support bundle: failed to create usage-reporting.json.txt:", err)
 	} else {
-		files = append(files, fileEntry{name: "usage-reporting.json.txt", data: usageReportingData})
+		if usageReportingData, err := json.MarshalIndent(r, "", "  "); err != nil {
+			l.Warnln("Support bundle: failed to serialize usage-reporting.json.txt", err)
+		} else {
+			files = append(files, fileEntry{name: "usage-reporting.json.txt", data: usageReportingData})
+
+		}
 	}
 
 	// Heap and CPU Proofs as a pprof extension
@@ -1148,7 +1153,13 @@ func (s *service) getReport(w http.ResponseWriter, r *http.Request) {
 	if val, _ := strconv.Atoi(r.URL.Query().Get("version")); val > 0 {
 		version = val
 	}
-	sendJSON(w, s.urService.ReportDataPreview(context.TODO(), version))
+	if r, err := s.urService.ReportDataPreview(context.TODO(), version); err != nil {
+		http.Error(w, err.Error(), 500)
+		return
+	} else {
+		sendJSON(w, r)
+	}
+
 }
 
 func (s *service) getRandomString(w http.ResponseWriter, r *http.Request) {
diff --git a/lib/api/mocked_model_test.go b/lib/api/mocked_model_test.go
index 24eba2533..553507c4c 100644
--- a/lib/api/mocked_model_test.go
+++ b/lib/api/mocked_model_test.go
@@ -15,6 +15,7 @@ import (
 	"github.com/syncthing/syncthing/lib/model"
 	"github.com/syncthing/syncthing/lib/protocol"
 	"github.com/syncthing/syncthing/lib/stats"
+	"github.com/syncthing/syncthing/lib/ur/contract"
 	"github.com/syncthing/syncthing/lib/versioner"
 )
 
@@ -112,8 +113,7 @@ func (m *mockedModel) State(folder string) (string, time.Time, error) {
 	return "", time.Time{}, nil
 }
 
-func (m *mockedModel) UsageReportingStats(version int, preview bool) map[string]interface{} {
-	return nil
+func (m *mockedModel) UsageReportingStats(r *contract.Report, version int, preview bool) {
 }
 
 func (m *mockedModel) FolderErrors(folder string) ([]model.FileError, error) {
diff --git a/lib/model/model.go b/lib/model/model.go
index a8aa77926..3e95dd937 100644
--- a/lib/model/model.go
+++ b/lib/model/model.go
@@ -34,6 +34,7 @@ import (
 	"github.com/syncthing/syncthing/lib/scanner"
 	"github.com/syncthing/syncthing/lib/stats"
 	"github.com/syncthing/syncthing/lib/sync"
+	"github.com/syncthing/syncthing/lib/ur/contract"
 	"github.com/syncthing/syncthing/lib/util"
 	"github.com/syncthing/syncthing/lib/versioner"
 )
@@ -101,7 +102,7 @@ type Model interface {
 	ConnectionStats() map[string]interface{}
 	DeviceStatistics() (map[string]stats.DeviceStatistics, error)
 	FolderStatistics() (map[string]stats.FolderStatistics, error)
-	UsageReportingStats(version int, preview bool) map[string]interface{}
+	UsageReportingStats(report *contract.Report, version int, preview bool)
 
 	StartDeadlockDetector(timeout time.Duration)
 	GlobalDirectoryTree(folder, prefix string, levels int, dirsonly bool) map[string]interface{}
@@ -443,7 +444,7 @@ func (m *model) stopFolder(cfg config.FolderConfiguration, err error) {
 
 // Need to hold lock on m.fmut when calling this.
 func (m *model) cleanupFolderLocked(cfg config.FolderConfiguration) {
-	// Clean up our config maps
+	// clear up our config maps
 	delete(m.folderCfgs, cfg.ID)
 	delete(m.folderFiles, cfg.ID)
 	delete(m.folderIgnores, cfg.ID)
@@ -520,49 +521,49 @@ func (m *model) newFolder(cfg config.FolderConfiguration) {
 	m.addAndStartFolderLocked(cfg, fset)
 }
 
-func (m *model) UsageReportingStats(version int, preview bool) map[string]interface{} {
-	stats := make(map[string]interface{})
+func (m *model) UsageReportingStats(report *contract.Report, version int, preview bool) {
 	if version >= 3 {
 		// Block stats
 		blockStatsMut.Lock()
-		copyBlockStats := make(map[string]int)
 		for k, v := range blockStats {
-			copyBlockStats[k] = v
+			switch k {
+			case "total":
+				report.BlockStats.Total = v
+			case "renamed":
+				report.BlockStats.Renamed = v
+			case "reused":
+				report.BlockStats.Reused = v
+			case "pulled":
+				report.BlockStats.Pulled = v
+			case "copyOrigin":
+				report.BlockStats.CopyOrigin = v
+			case "copyOriginShifted":
+				report.BlockStats.CopyOriginShifted = v
+			case "copyElsewhere":
+				report.BlockStats.CopyElsewhere = v
+			}
+			// Reset counts, as these are incremental
 			if !preview {
 				blockStats[k] = 0
 			}
 		}
 		blockStatsMut.Unlock()
-		stats["blockStats"] = copyBlockStats
 
 		// Transport stats
 		m.pmut.RLock()
-		transportStats := make(map[string]int)
 		for _, conn := range m.conn {
-			transportStats[conn.Transport()]++
+			report.TransportStats[conn.Transport()]++
 		}
 		m.pmut.RUnlock()
-		stats["transportStats"] = transportStats
 
 		// Ignore stats
-		ignoreStats := map[string]int{
-			"lines":           0,
-			"inverts":         0,
-			"folded":          0,
-			"deletable":       0,
-			"rooted":          0,
-			"includes":        0,
-			"escapedIncludes": 0,
-			"doubleStars":     0,
-			"stars":           0,
-		}
 		var seenPrefix [3]bool
 		for folder := range m.cfg.Folders() {
 			lines, _, err := m.GetIgnores(folder)
 			if err != nil {
 				continue
 			}
-			ignoreStats["lines"] += len(lines)
+			report.IgnoreStats.Lines += len(lines)
 
 			for _, line := range lines {
 				// Allow prefixes to be specified in any order, but only once.
@@ -570,15 +571,15 @@ func (m *model) UsageReportingStats(version int, preview bool) map[string]interf
 					if strings.HasPrefix(line, "!") && !seenPrefix[0] {
 						seenPrefix[0] = true
 						line = line[1:]
-						ignoreStats["inverts"] += 1
+						report.IgnoreStats.Inverts++
 					} else if strings.HasPrefix(line, "(?i)") && !seenPrefix[1] {
 						seenPrefix[1] = true
 						line = line[4:]
-						ignoreStats["folded"] += 1
+						report.IgnoreStats.Folded++
 					} else if strings.HasPrefix(line, "(?d)") && !seenPrefix[2] {
 						seenPrefix[2] = true
 						line = line[4:]
-						ignoreStats["deletable"] += 1
+						report.IgnoreStats.Deletable++
 					} else {
 						seenPrefix[0] = false
 						seenPrefix[1] = false
@@ -592,28 +593,26 @@ func (m *model) UsageReportingStats(version int, preview bool) map[string]interf
 				line = strings.TrimPrefix(line, "**/")
 
 				if strings.HasPrefix(line, "/") {
-					ignoreStats["rooted"] += 1
+					report.IgnoreStats.Rooted++
 				} else if strings.HasPrefix(line, "#include ") {
-					ignoreStats["includes"] += 1
+					report.IgnoreStats.Includes++
 					if strings.Contains(line, "..") {
-						ignoreStats["escapedIncludes"] += 1
+						report.IgnoreStats.EscapedIncludes++
 					}
 				}
 
 				if strings.Contains(line, "**") {
-					ignoreStats["doubleStars"] += 1
+					report.IgnoreStats.DoubleStars++
 					// Remove not to trip up star checks.
 					line = strings.Replace(line, "**", "", -1)
 				}
 
 				if strings.Contains(line, "*") {
-					ignoreStats["stars"] += 1
+					report.IgnoreStats.Stars++
 				}
 			}
 		}
-		stats["ignoreStats"] = ignoreStats
 	}
-	return stats
 }
 
 type ConnectionInfo struct {
diff --git a/lib/ur/contract/contract.go b/lib/ur/contract/contract.go
new file mode 100644
index 000000000..a2eb6454e
--- /dev/null
+++ b/lib/ur/contract/contract.go
@@ -0,0 +1,425 @@
+// Copyright (C) 2020 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package contract
+
+import (
+	"database/sql/driver"
+	"encoding/json"
+	"errors"
+	"reflect"
+	"strconv"
+	"time"
+)
+
+type Report struct {
+	// Generated
+	Received time.Time `json:"-"` // Only from DB
+	Date     string    `json:"date,omitempty"`
+	Address  string    `json:"address,omitempty"`
+
+	// v1 fields
+
+	UniqueID       string  `json:"uniqueID,omitempty" since:"1"`
+	Version        string  `json:"version,omitempty" since:"1"`
+	LongVersion    string  `json:"longVersion,omitempty" since:"1"`
+	Platform       string  `json:"platform,omitempty" since:"1"`
+	NumFolders     int     `json:"numFolders,omitempty" since:"1"`
+	NumDevices     int     `json:"numDevices,omitempty" since:"1"`
+	TotFiles       int     `json:"totFiles,omitempty" since:"1"`
+	FolderMaxFiles int     `json:"folderMaxFiles,omitempty" since:"1"`
+	TotMiB         int     `json:"totMiB,omitempty" since:"1"`
+	FolderMaxMiB   int     `json:"folderMaxMiB,omitempty" since:"1"`
+	MemoryUsageMiB int     `json:"memoryUsageMiB,omitempty" since:"1"`
+	SHA256Perf     float64 `json:"sha256Perf,omitempty" since:"1"`
+	HashPerf       float64 `json:"hashPerf,omitempty" since:"1"` // Was previously not stored server-side
+	MemorySize     int     `json:"memorySize,omitempty" since:"1"`
+
+	// v2 fields
+
+	URVersion  int `json:"urVersion,omitempty" since:"2"`
+	NumCPU     int `json:"numCPU,omitempty" since:"2"`
+	FolderUses struct {
+		SendOnly            int `json:"sendonly,omitempty" since:"2"`
+		SendReceive         int `json:"sendreceive,omitempty" since:"2"` // Was previously not stored server-side
+		ReceiveOnly         int `json:"receiveonly,omitempty" since:"2"`
+		IgnorePerms         int `json:"ignorePerms,omitempty" since:"2"`
+		IgnoreDelete        int `json:"ignoreDelete,omitempty" since:"2"`
+		AutoNormalize       int `json:"autoNormalize,omitempty" since:"2"`
+		SimpleVersioning    int `json:"simpleVersioning,omitempty" since:"2"`
+		ExternalVersioning  int `json:"externalVersioning,omitempty" since:"2"`
+		StaggeredVersioning int `json:"staggeredVersioning,omitempty" since:"2"`
+		TrashcanVersioning  int `json:"trashcanVersioning,omitempty" since:"2"`
+	} `json:"folderUses,omitempty" since:"2"`
+
+	DeviceUses struct {
+		Introducer       int `json:"introducer,omitempty" since:"2"`
+		CustomCertName   int `json:"customCertName,omitempty" since:"2"`
+		CompressAlways   int `json:"compressAlways,omitempty" since:"2"`
+		CompressMetadata int `json:"compressMetadata,omitempty" since:"2"`
+		CompressNever    int `json:"compressNever,omitempty" since:"2"`
+		DynamicAddr      int `json:"dynamicAddr,omitempty" since:"2"`
+		StaticAddr       int `json:"staticAddr,omitempty" since:"2"`
+	} `json:"deviceUses,omitempty" since:"2"`
+
+	Announce struct {
+		GlobalEnabled     bool `json:"globalEnabled,omitempty" since:"2"`
+		LocalEnabled      bool `json:"localEnabled,omitempty" since:"2"`
+		DefaultServersDNS int  `json:"defaultServersDNS,omitempty" since:"2"`
+		DefaultServersIP  int  `json:"defaultServersIP,omitempty" since:"2"` // Deprecated and not provided client-side anymore
+		OtherServers      int  `json:"otherServers,omitempty" since:"2"`
+	} `json:"announce,omitempty" since:"2"`
+
+	Relays struct {
+		Enabled        bool `json:"enabled,omitempty" since:"2"`
+		DefaultServers int  `json:"defaultServers,omitempty" since:"2"`
+		OtherServers   int  `json:"otherServers,omitempty" since:"2"`
+	} `json:"relays,omitempty" since:"2"`
+
+	UsesRateLimit        bool `json:"usesRateLimit,omitempty" since:"2"`
+	UpgradeAllowedManual bool `json:"upgradeAllowedManual,omitempty" since:"2"`
+	UpgradeAllowedAuto   bool `json:"upgradeAllowedAuto,omitempty" since:"2"`
+
+	// V2.5 fields (fields that were in v2 but never added to the database
+	UpgradeAllowedPre bool  `json:"upgradeAllowedPre,omitempty" since:"2"`
+	RescanIntvs       []int `json:"rescanIntvs,omitempty" since:"2"`
+
+	// v3 fields
+
+	Uptime                     int    `json:"uptime,omitempty" since:"3"`
+	NATType                    string `json:"natType,omitempty" since:"3"`
+	AlwaysLocalNets            bool   `json:"alwaysLocalNets,omitempty" since:"3"`
+	CacheIgnoredFiles          bool   `json:"cacheIgnoredFiles,omitempty" since:"3"`
+	OverwriteRemoteDeviceNames bool   `json:"overwriteRemoteDeviceNames,omitempty" since:"3"`
+	ProgressEmitterEnabled     bool   `json:"progressEmitterEnabled,omitempty" since:"3"`
+	CustomDefaultFolderPath    bool   `json:"customDefaultFolderPath,omitempty" since:"3"`
+	WeakHashSelection          string `json:"weakHashSelection,omitempty" since:"3"` // Deprecated and not provided client-side anymore
+	CustomTrafficClass         bool   `json:"customTrafficClass,omitempty" since:"3"`
+	CustomTempIndexMinBlocks   bool   `json:"customTempIndexMinBlocks,omitempty" since:"3"`
+	TemporariesDisabled        bool   `json:"temporariesDisabled,omitempty" since:"3"`
+	TemporariesCustom          bool   `json:"temporariesCustom,omitempty" since:"3"`
+	LimitBandwidthInLan        bool   `json:"limitBandwidthInLan,omitempty" since:"3"`
+	CustomReleaseURL           bool   `json:"customReleaseURL,omitempty" since:"3"`
+	RestartOnWakeup            bool   `json:"restartOnWakeup,omitempty" since:"3"`
+	CustomStunServers          bool   `json:"customStunServers,omitempty" since:"3"`
+
+	FolderUsesV3 struct {
+		ScanProgressDisabled    int            `json:"scanProgressDisabled,omitempty" since:"3"`
+		ConflictsDisabled       int            `json:"conflictsDisabled,omitempty" since:"3"`
+		ConflictsUnlimited      int            `json:"conflictsUnlimited,omitempty" since:"3"`
+		ConflictsOther          int            `json:"conflictsOther,omitempty" since:"3"`
+		DisableSparseFiles      int            `json:"disableSparseFiles,omitempty" since:"3"`
+		DisableTempIndexes      int            `json:"disableTempIndexes,omitempty" since:"3"`
+		AlwaysWeakHash          int            `json:"alwaysWeakHash,omitempty" since:"3"`
+		CustomWeakHashThreshold int            `json:"customWeakHashThreshold,omitempty" since:"3"`
+		FsWatcherEnabled        int            `json:"fsWatcherEnabled,omitempty" since:"3"`
+		PullOrder               map[string]int `json:"pullOrder,omitempty" since:"3"`
+		FilesystemType          map[string]int `json:"filesystemType,omitempty" since:"3"`
+		FsWatcherDelays         []int          `json:"fsWatcherDelays,omitempty" since:"3"`
+	} `json:"folderUsesV3,omitempty" since:"3"`
+
+	GUIStats struct {
+		Enabled                   int            `json:"enabled,omitempty" since:"3"`
+		UseTLS                    int            `json:"useTLS,omitempty" since:"3"`
+		UseAuth                   int            `json:"useAuth,omitempty" since:"3"`
+		InsecureAdminAccess       int            `json:"insecureAdminAccess,omitempty" since:"3"`
+		Debugging                 int            `json:"debugging,omitempty" since:"3"`
+		InsecureSkipHostCheck     int            `json:"insecureSkipHostCheck,omitempty" since:"3"`
+		InsecureAllowFrameLoading int            `json:"insecureAllowFrameLoading,omitempty" since:"3"`
+		ListenLocal               int            `json:"listenLocal,omitempty" since:"3"`
+		ListenUnspecified         int            `json:"listenUnspecified,omitempty" since:"3"`
+		Theme                     map[string]int `json:"theme,omitempty" since:"3"`
+	} `json:"guiStats,omitempty" since:"3"`
+
+	BlockStats struct {
+		Total             int `json:"total,omitempty" since:"3"`
+		Renamed           int `json:"renamed,omitempty" since:"3"`
+		Reused            int `json:"reused,omitempty" since:"3"`
+		Pulled            int `json:"pulled,omitempty" since:"3"`
+		CopyOrigin        int `json:"copyOrigin,omitempty" since:"3"`
+		CopyOriginShifted int `json:"copyOriginShifted,omitempty" since:"3"`
+		CopyElsewhere     int `json:"copyElsewhere,omitempty" since:"3"`
+	} `json:"blockStats,omitempty" since:"3"`
+
+	TransportStats map[string]int `json:"transportStats,omitempty" since:"3"`
+
+	IgnoreStats struct {
+		Lines           int `json:"lines,omitempty" since:"3"`
+		Inverts         int `json:"inverts,omitempty" since:"3"`
+		Folded          int `json:"folded,omitempty" since:"3"`
+		Deletable       int `json:"deletable,omitempty" since:"3"`
+		Rooted          int `json:"rooted,omitempty" since:"3"`
+		Includes        int `json:"includes,omitempty" since:"3"`
+		EscapedIncludes int `json:"escapedIncludes,omitempty" since:"3"`
+		DoubleStars     int `json:"doubleStars,omitempty" since:"3"`
+		Stars           int `json:"stars,omitempty" since:"3"`
+	} `json:"ignoreStats,omitempty" since:"3"`
+
+	// V3 fields added late in the RC
+	WeakHashEnabled bool `json:"weakHashEnabled,omitempty" since:"3"` // Deprecated and not provided client-side anymore
+}
+
+func New() *Report {
+	r := &Report{}
+	r.FolderUsesV3.PullOrder = make(map[string]int)
+	r.FolderUsesV3.FilesystemType = make(map[string]int)
+	r.GUIStats.Theme = make(map[string]int)
+	r.TransportStats = make(map[string]int)
+	r.RescanIntvs = make([]int, 0)
+	r.FolderUsesV3.FsWatcherDelays = make([]int, 0)
+	return r
+}
+
+func (r *Report) Validate() error {
+	if r.UniqueID == "" || r.Version == "" || r.Platform == "" {
+		return errors.New("missing required field")
+	}
+	if len(r.Date) != 8 {
+		return errors.New("date not initialized")
+	}
+
+	// Some fields may not be null.
+	if r.RescanIntvs == nil {
+		r.RescanIntvs = []int{}
+	}
+	if r.FolderUsesV3.FsWatcherDelays == nil {
+		r.FolderUsesV3.FsWatcherDelays = []int{}
+	}
+
+	return nil
+}
+
+func (r *Report) ClearForVersion(version int) error {
+	return clear(r, version)
+}
+
+func (r *Report) FieldPointers() []interface{} {
+	// All the fields of the Report, in the same order as the database fields.
+	return []interface{}{
+		&r.Received, &r.UniqueID, &r.Version, &r.LongVersion, &r.Platform,
+		&r.NumFolders, &r.NumDevices, &r.TotFiles, &r.FolderMaxFiles,
+		&r.TotMiB, &r.FolderMaxMiB, &r.MemoryUsageMiB, &r.SHA256Perf,
+		&r.MemorySize, &r.Date,
+		// V2
+		&r.URVersion, &r.NumCPU, &r.FolderUses.SendOnly, &r.FolderUses.IgnorePerms,
+		&r.FolderUses.IgnoreDelete, &r.FolderUses.AutoNormalize, &r.DeviceUses.Introducer,
+		&r.DeviceUses.CustomCertName, &r.DeviceUses.CompressAlways,
+		&r.DeviceUses.CompressMetadata, &r.DeviceUses.CompressNever,
+		&r.DeviceUses.DynamicAddr, &r.DeviceUses.StaticAddr,
+		&r.Announce.GlobalEnabled, &r.Announce.LocalEnabled,
+		&r.Announce.DefaultServersDNS, &r.Announce.DefaultServersIP,
+		&r.Announce.OtherServers, &r.Relays.Enabled, &r.Relays.DefaultServers,
+		&r.Relays.OtherServers, &r.UsesRateLimit, &r.UpgradeAllowedManual,
+		&r.UpgradeAllowedAuto, &r.FolderUses.SimpleVersioning,
+		&r.FolderUses.ExternalVersioning, &r.FolderUses.StaggeredVersioning,
+		&r.FolderUses.TrashcanVersioning,
+
+		// V2.5
+		&r.UpgradeAllowedPre,
+
+		// V3
+		&r.Uptime, &r.NATType, &r.AlwaysLocalNets, &r.CacheIgnoredFiles,
+		&r.OverwriteRemoteDeviceNames, &r.ProgressEmitterEnabled, &r.CustomDefaultFolderPath,
+		&r.WeakHashSelection, &r.CustomTrafficClass, &r.CustomTempIndexMinBlocks,
+		&r.TemporariesDisabled, &r.TemporariesCustom, &r.LimitBandwidthInLan,
+		&r.CustomReleaseURL, &r.RestartOnWakeup, &r.CustomStunServers,
+
+		&r.FolderUsesV3.ScanProgressDisabled, &r.FolderUsesV3.ConflictsDisabled,
+		&r.FolderUsesV3.ConflictsUnlimited, &r.FolderUsesV3.ConflictsOther,
+		&r.FolderUsesV3.DisableSparseFiles, &r.FolderUsesV3.DisableTempIndexes,
+		&r.FolderUsesV3.AlwaysWeakHash, &r.FolderUsesV3.CustomWeakHashThreshold,
+		&r.FolderUsesV3.FsWatcherEnabled,
+
+		&r.GUIStats.Enabled, &r.GUIStats.UseTLS, &r.GUIStats.UseAuth,
+		&r.GUIStats.InsecureAdminAccess,
+		&r.GUIStats.Debugging, &r.GUIStats.InsecureSkipHostCheck,
+		&r.GUIStats.InsecureAllowFrameLoading, &r.GUIStats.ListenLocal,
+		&r.GUIStats.ListenUnspecified,
+
+		&r.BlockStats.Total, &r.BlockStats.Renamed,
+		&r.BlockStats.Reused, &r.BlockStats.Pulled, &r.BlockStats.CopyOrigin,
+		&r.BlockStats.CopyOriginShifted, &r.BlockStats.CopyElsewhere,
+
+		&r.IgnoreStats.Lines, &r.IgnoreStats.Inverts, &r.IgnoreStats.Folded,
+		&r.IgnoreStats.Deletable, &r.IgnoreStats.Rooted, &r.IgnoreStats.Includes,
+		&r.IgnoreStats.EscapedIncludes, &r.IgnoreStats.DoubleStars, &r.IgnoreStats.Stars,
+
+		// V3 added late in the RC
+		&r.WeakHashEnabled,
+		&r.Address,
+
+		// Receive only folders
+		&r.FolderUses.ReceiveOnly,
+	}
+}
+
+func (r *Report) FieldNames() []string {
+	// The database fields that back this struct in PostgreSQL
+	return []string{
+		// V1
+		"Received",
+		"UniqueID",
+		"Version",
+		"LongVersion",
+		"Platform",
+		"NumFolders",
+		"NumDevices",
+		"TotFiles",
+		"FolderMaxFiles",
+		"TotMiB",
+		"FolderMaxMiB",
+		"MemoryUsageMiB",
+		"SHA256Perf",
+		"MemorySize",
+		"Date",
+		// V2
+		"ReportVersion",
+		"NumCPU",
+		"FolderRO",
+		"FolderIgnorePerms",
+		"FolderIgnoreDelete",
+		"FolderAutoNormalize",
+		"DeviceIntroducer",
+		"DeviceCustomCertName",
+		"DeviceCompressAlways",
+		"DeviceCompressMetadata",
+		"DeviceCompressNever",
+		"DeviceDynamicAddr",
+		"DeviceStaticAddr",
+		"AnnounceGlobalEnabled",
+		"AnnounceLocalEnabled",
+		"AnnounceDefaultServersDNS",
+		"AnnounceDefaultServersIP",
+		"AnnounceOtherServers",
+		"RelayEnabled",
+		"RelayDefaultServers",
+		"RelayOtherServers",
+		"RateLimitEnabled",
+		"UpgradeAllowedManual",
+		"UpgradeAllowedAuto",
+		// v0.12.19+
+		"FolderSimpleVersioning",
+		"FolderExternalVersioning",
+		"FolderStaggeredVersioning",
+		"FolderTrashcanVersioning",
+		// V2.5
+		"UpgradeAllowedPre",
+		// V3
+		"Uptime",
+		"NATType",
+		"AlwaysLocalNets",
+		"CacheIgnoredFiles",
+		"OverwriteRemoteDeviceNames",
+		"ProgressEmitterEnabled",
+		"CustomDefaultFolderPath",
+		"WeakHashSelection",
+		"CustomTrafficClass",
+		"CustomTempIndexMinBlocks",
+		"TemporariesDisabled",
+		"TemporariesCustom",
+		"LimitBandwidthInLan",
+		"CustomReleaseURL",
+		"RestartOnWakeup",
+		"CustomStunServers",
+
+		"FolderScanProgressDisabled",
+		"FolderConflictsDisabled",
+		"FolderConflictsUnlimited",
+		"FolderConflictsOther",
+		"FolderDisableSparseFiles",
+		"FolderDisableTempIndexes",
+		"FolderAlwaysWeakHash",
+		"FolderCustomWeakHashThreshold",
+		"FolderFsWatcherEnabled",
+
+		"GUIEnabled",
+		"GUIUseTLS",
+		"GUIUseAuth",
+		"GUIInsecureAdminAccess",
+		"GUIDebugging",
+		"GUIInsecureSkipHostCheck",
+		"GUIInsecureAllowFrameLoading",
+		"GUIListenLocal",
+		"GUIListenUnspecified",
+
+		"BlocksTotal",
+		"BlocksRenamed",
+		"BlocksReused",
+		"BlocksPulled",
+		"BlocksCopyOrigin",
+		"BlocksCopyOriginShifted",
+		"BlocksCopyElsewhere",
+
+		"IgnoreLines",
+		"IgnoreInverts",
+		"IgnoreFolded",
+		"IgnoreDeletable",
+		"IgnoreRooted",
+		"IgnoreIncludes",
+		"IgnoreEscapedIncludes",
+		"IgnoreDoubleStars",
+		"IgnoreStars",
+
+		// V3 added late in the RC
+		"WeakHashEnabled",
+		"Address",
+
+		// Receive only folders
+		"FolderRecvOnly",
+	}
+}
+
+func (r Report) Value() (driver.Value, error) {
+	// This needs to be string, yet we read back bytes..
+	bs, err := json.Marshal(r)
+	return string(bs), err
+}
+
+func (r *Report) Scan(value interface{}) error {
+	b, ok := value.([]byte)
+	if !ok {
+		return errors.New("type assertion to []byte failed")
+	}
+
+	return json.Unmarshal(b, &r)
+}
+
+func clear(v interface{}, since int) error {
+	s := reflect.ValueOf(v).Elem()
+	t := s.Type()
+
+	for i := 0; i < s.NumField(); i++ {
+		f := s.Field(i)
+		tag := t.Field(i).Tag
+
+		v := tag.Get("since")
+		if len(v) == 0 {
+			f.Set(reflect.Zero(f.Type()))
+			continue
+		}
+
+		vn, err := strconv.Atoi(v)
+		if err != nil {
+			return err
+		}
+		if vn > since {
+			f.Set(reflect.Zero(f.Type()))
+			continue
+		}
+
+		// Dive deeper
+		if f.Kind() == reflect.Ptr {
+			f = f.Elem()
+		}
+
+		if f.Kind() == reflect.Struct {
+			if err := clear(f.Addr().Interface(), since); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
diff --git a/lib/ur/contract/contract_test.go b/lib/ur/contract/contract_test.go
new file mode 100644
index 000000000..0f676af87
--- /dev/null
+++ b/lib/ur/contract/contract_test.go
@@ -0,0 +1,130 @@
+// Copyright (C) 2020 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package contract
+
+import (
+	"reflect"
+	"testing"
+)
+
+type PtrStruct struct {
+	A string         `since:"2"`
+	B map[string]int `since:"3"`
+}
+
+type Nested struct {
+	A float32 `since:"4"`
+	B [4]int  `since:"5"`
+	C bool    `since:"1"`
+}
+
+type TestStruct struct {
+	A      int
+	B      map[string]string `since:"1"`
+	C      []string          `since:"2"`
+	Nested Nested            `since:"3"`
+
+	Ptr *PtrStruct `since:"2"`
+}
+
+func testValue() TestStruct {
+	return TestStruct{
+		A: 1,
+		B: map[string]string{
+			"foo": "bar",
+		},
+		C: []string{"a", "b"},
+		Nested: Nested{
+			A: 0.10,
+			B: [4]int{1, 2, 3, 4},
+			C: true,
+		},
+		Ptr: &PtrStruct{
+			A: "value",
+			B: map[string]int{
+				"x": 1,
+				"b": 2,
+			},
+		},
+	}
+}
+
+func TestClean(t *testing.T) {
+	expect(t, 0, TestStruct{})
+
+	expect(t, 1, TestStruct{
+		// A unset, since it does not have "since"
+		B: map[string]string{
+			"foo": "bar",
+		},
+	})
+
+	expect(t, 2, TestStruct{
+		// A unset, since it does not have "since"
+		B: map[string]string{
+			"foo": "bar",
+		},
+		C: []string{"a", "b"},
+		Ptr: &PtrStruct{
+			A: "value",
+		},
+	})
+
+	expect(t, 3, TestStruct{
+		// A unset, since it does not have "since"
+		B: map[string]string{
+			"foo": "bar",
+		},
+		C: []string{"a", "b"},
+		Nested: Nested{
+			C: true,
+		},
+		Ptr: &PtrStruct{
+			A: "value",
+			B: map[string]int{
+				"x": 1,
+				"b": 2,
+			},
+		},
+	})
+
+	expect(t, 4, TestStruct{
+		// A unset, since it does not have "since"
+		B: map[string]string{
+			"foo": "bar",
+		},
+		C: []string{"a", "b"},
+		Nested: Nested{
+			A: 0.10,
+			C: true,
+		},
+		Ptr: &PtrStruct{
+			A: "value",
+			B: map[string]int{
+				"x": 1,
+				"b": 2,
+			},
+		},
+	})
+
+	x := testValue()
+	x.A = 0
+
+	expect(t, 5, x)
+	expect(t, 6, x)
+}
+
+func expect(t *testing.T, since int, b interface{}) {
+	t.Helper()
+	x := testValue()
+	if err := clear(&x, since); err != nil {
+		t.Fatal(err.Error())
+	}
+	if !reflect.DeepEqual(x, b) {
+		t.Errorf("%#v != %#v", x, b)
+	}
+}
diff --git a/lib/ur/memsize_darwin.go b/lib/ur/memsize_darwin.go
index b88d3fdb9..0d19921e0 100644
--- a/lib/ur/memsize_darwin.go
+++ b/lib/ur/memsize_darwin.go
@@ -8,7 +8,10 @@ package ur
 
 import "golang.org/x/sys/unix"
 
-func memorySize() (int64, error) {
+func memorySize() int64 {
 	mem, err := unix.SysctlUint64("hw.memsize")
-	return int64(mem), err
+	if err != nil {
+		return 0
+	}
+	return int64(mem)
 }
diff --git a/lib/ur/memsize_linux.go b/lib/ur/memsize_linux.go
index ca6d9edb7..2be03aa95 100644
--- a/lib/ur/memsize_linux.go
+++ b/lib/ur/memsize_linux.go
@@ -8,32 +8,31 @@ package ur
 
 import (
 	"bufio"
-	"errors"
 	"os"
 	"strconv"
 	"strings"
 )
 
-func memorySize() (int64, error) {
+func memorySize() int64 {
 	f, err := os.Open("/proc/meminfo")
 	if err != nil {
-		return 0, err
+		return 0
 	}
 
 	s := bufio.NewScanner(f)
 	if !s.Scan() {
-		return 0, errors.New("/proc/meminfo parse error 1")
+		return 0
 	}
 
 	l := s.Text()
 	fs := strings.Fields(l)
 	if len(fs) != 3 || fs[2] != "kB" {
-		return 0, errors.New("/proc/meminfo parse error 2")
+		return 0
 	}
 
 	kb, err := strconv.ParseInt(fs[1], 10, 64)
 	if err != nil {
-		return 0, err
+		return 0
 	}
-	return kb * 1024, nil
+	return kb * 1024
 }
diff --git a/lib/ur/memsize_netbsd.go b/lib/ur/memsize_netbsd.go
index 3fd4a77a6..7a0568bca 100644
--- a/lib/ur/memsize_netbsd.go
+++ b/lib/ur/memsize_netbsd.go
@@ -7,25 +7,24 @@
 package ur
 
 import (
-	"errors"
 	"os/exec"
 	"strconv"
 	"strings"
 )
 
-func memorySize() (int64, error) {
+func memorySize() int64 {
 	cmd := exec.Command("/sbin/sysctl", "hw.physmem64")
 	out, err := cmd.Output()
 	if err != nil {
-		return 0, err
+		return 0
 	}
 	fs := strings.Fields(string(out))
 	if len(fs) != 3 {
-		return 0, errors.New("sysctl parse error")
+		return 0
 	}
 	bytes, err := strconv.ParseInt(fs[2], 10, 64)
 	if err != nil {
-		return 0, err
+		return 0
 	}
-	return bytes, nil
+	return bytes
 }
diff --git a/lib/ur/memsize_solaris.go b/lib/ur/memsize_solaris.go
index 23965fd05..cd805b736 100644
--- a/lib/ur/memsize_solaris.go
+++ b/lib/ur/memsize_solaris.go
@@ -13,16 +13,16 @@ import (
 	"strconv"
 )
 
-func memorySize() (int64, error) {
+func memorySize() int64 {
 	cmd := exec.Command("prtconf", "-m")
 	out, err := cmd.CombinedOutput()
 	if err != nil {
-		return 0, err
+		return 0
 	}
 
 	mb, err := strconv.ParseInt(string(out), 10, 64)
 	if err != nil {
-		return 0, err
+		return 0
 	}
-	return mb * 1024 * 1024, nil
+	return mb * 1024 * 1024
 }
diff --git a/lib/ur/memsize_unimpl.go b/lib/ur/memsize_unimpl.go
index 0b4d792f7..5a80b1a27 100644
--- a/lib/ur/memsize_unimpl.go
+++ b/lib/ur/memsize_unimpl.go
@@ -8,8 +8,6 @@
 
 package ur
 
-import "errors"
-
-func memorySize() (int64, error) {
-	return 0, errors.New("not implemented")
+func memorySize() int64 {
+	return 0
 }
diff --git a/lib/ur/memsize_windows.go b/lib/ur/memsize_windows.go
index 92c780829..a6a70419e 100644
--- a/lib/ur/memsize_windows.go
+++ b/lib/ur/memsize_windows.go
@@ -17,14 +17,14 @@ var (
 	globalMemoryStatusEx, _ = syscall.GetProcAddress(kernel32, "GlobalMemoryStatusEx")
 )
 
-func memorySize() (int64, error) {
+func memorySize() int64 {
 	var memoryStatusEx [64]byte
 	binary.LittleEndian.PutUint32(memoryStatusEx[:], 64)
 
-	ret, _, callErr := syscall.Syscall(uintptr(globalMemoryStatusEx), 1, uintptr(unsafe.Pointer(&memoryStatusEx[0])), 0, 0)
+	ret, _, _ := syscall.Syscall(uintptr(globalMemoryStatusEx), 1, uintptr(unsafe.Pointer(&memoryStatusEx[0])), 0, 0)
 	if ret == 0 {
-		return 0, callErr
+		return 0
 	}
 
-	return int64(binary.LittleEndian.Uint64(memoryStatusEx[8:])), nil
+	return int64(binary.LittleEndian.Uint64(memoryStatusEx[8:]))
 }
diff --git a/lib/ur/usage_report.go b/lib/ur/usage_report.go
index 30282d199..e56130084 100644
--- a/lib/ur/usage_report.go
+++ b/lib/ur/usage_report.go
@@ -28,6 +28,7 @@ import (
 	"github.com/syncthing/syncthing/lib/protocol"
 	"github.com/syncthing/syncthing/lib/scanner"
 	"github.com/syncthing/syncthing/lib/upgrade"
+	"github.com/syncthing/syncthing/lib/ur/contract"
 	"github.com/syncthing/syncthing/lib/util"
 
 	"github.com/thejerf/suture"
@@ -63,27 +64,19 @@ func New(cfg config.Wrapper, m model.Model, connectionsService connections.Servi
 
 // ReportData returns the data to be sent in a usage report with the currently
 // configured usage reporting version.
-func (s *Service) ReportData(ctx context.Context) map[string]interface{} {
+func (s *Service) ReportData(ctx context.Context) (*contract.Report, error) {
 	urVersion := s.cfg.Options().URAccepted
 	return s.reportData(ctx, urVersion, false)
 }
 
 // ReportDataPreview returns a preview of the data to be sent in a usage report
 // with the given version.
-func (s *Service) ReportDataPreview(ctx context.Context, urVersion int) map[string]interface{} {
+func (s *Service) ReportDataPreview(ctx context.Context, urVersion int) (*contract.Report, error) {
 	return s.reportData(ctx, urVersion, true)
 }
 
-func (s *Service) reportData(ctx context.Context, urVersion int, preview bool) map[string]interface{} {
+func (s *Service) reportData(ctx context.Context, urVersion int, preview bool) (*contract.Report, error) {
 	opts := s.cfg.Options()
-	res := make(map[string]interface{})
-	res["urVersion"] = urVersion
-	res["uniqueID"] = opts.URUniqueID
-	res["version"] = build.Version
-	res["longVersion"] = build.LongVersion
-	res["platform"] = runtime.GOOS + "-" + runtime.GOARCH
-	res["numFolders"] = len(s.cfg.Folders())
-	res["numDevices"] = len(s.cfg.Devices())
 
 	var totFiles, maxFiles int
 	var totBytes, maxBytes int64
@@ -104,264 +97,211 @@ func (s *Service) reportData(ctx context.Context, urVersion int, preview bool) m
 		}
 	}
 
-	res["totFiles"] = totFiles
-	res["folderMaxFiles"] = maxFiles
-	res["totMiB"] = totBytes / 1024 / 1024
-	res["folderMaxMiB"] = maxBytes / 1024 / 1024
-
 	var mem runtime.MemStats
 	runtime.ReadMemStats(&mem)
-	res["memoryUsageMiB"] = (mem.Sys - mem.HeapReleased) / 1024 / 1024
-	res["sha256Perf"] = CpuBench(ctx, 5, 125*time.Millisecond, false)
-	res["hashPerf"] = CpuBench(ctx, 5, 125*time.Millisecond, true)
 
-	bytes, err := memorySize()
-	if err == nil {
-		res["memorySize"] = bytes / 1024 / 1024
-	}
-	res["numCPU"] = runtime.NumCPU()
+	report := contract.New()
+
+	report.URVersion = urVersion
+	report.UniqueID = opts.URUniqueID
+	report.Version = build.Version
+	report.LongVersion = build.LongVersion
+	report.Platform = runtime.GOOS + "-" + runtime.GOARCH
+	report.NumFolders = len(s.cfg.Folders())
+	report.NumDevices = len(s.cfg.Devices())
+	report.TotFiles = totFiles
+	report.FolderMaxFiles = maxFiles
+	report.TotMiB = int(totBytes / 1024 / 1024)
+	report.FolderMaxMiB = int(maxBytes / 1024 / 1024)
+	report.MemoryUsageMiB = int((mem.Sys - mem.HeapReleased) / 1024 / 1024)
+	report.SHA256Perf = CpuBench(ctx, 5, 125*time.Millisecond, false)
+	report.HashPerf = CpuBench(ctx, 5, 125*time.Millisecond, true)
+	report.MemorySize = int(memorySize() / 1024 / 1024)
+	report.NumCPU = runtime.NumCPU()
 
-	var rescanIntvs []int
-	folderUses := map[string]int{
-		"sendonly":            0,
-		"sendreceive":         0,
-		"receiveonly":         0,
-		"ignorePerms":         0,
-		"ignoreDelete":        0,
-		"autoNormalize":       0,
-		"simpleVersioning":    0,
-		"externalVersioning":  0,
-		"staggeredVersioning": 0,
-		"trashcanVersioning":  0,
-	}
 	for _, cfg := range s.cfg.Folders() {
-		rescanIntvs = append(rescanIntvs, cfg.RescanIntervalS)
+		report.RescanIntvs = append(report.RescanIntvs, cfg.RescanIntervalS)
 
 		switch cfg.Type {
 		case config.FolderTypeSendOnly:
-			folderUses["sendonly"]++
+			report.FolderUses.SendOnly++
 		case config.FolderTypeSendReceive:
-			folderUses["sendreceive"]++
+			report.FolderUses.SendReceive++
 		case config.FolderTypeReceiveOnly:
-			folderUses["receiveonly"]++
+			report.FolderUses.ReceiveOnly++
 		}
 		if cfg.IgnorePerms {
-			folderUses["ignorePerms"]++
+			report.FolderUses.IgnorePerms++
 		}
 		if cfg.IgnoreDelete {
-			folderUses["ignoreDelete"]++
+			report.FolderUses.IgnoreDelete++
 		}
 		if cfg.AutoNormalize {
-			folderUses["autoNormalize"]++
+			report.FolderUses.AutoNormalize++
 		}
-		if cfg.Versioning.Type != "" {
-			folderUses[cfg.Versioning.Type+"Versioning"]++
+		switch cfg.Versioning.Type {
+		case "":
+			// None
+		case "simple":
+			report.FolderUses.SimpleVersioning++
+		case "staggered":
+			report.FolderUses.StaggeredVersioning++
+		case "external":
+			report.FolderUses.ExternalVersioning++
+		case "trashcan":
+			report.FolderUses.TrashcanVersioning++
+		default:
+			l.Warnf("Unhandled versioning type for usage reports: %s", cfg.Versioning.Type)
 		}
 	}
-	sort.Ints(rescanIntvs)
-	res["rescanIntvs"] = rescanIntvs
-	res["folderUses"] = folderUses
+	sort.Ints(report.RescanIntvs)
 
-	deviceUses := map[string]int{
-		"introducer":       0,
-		"customCertName":   0,
-		"compressAlways":   0,
-		"compressMetadata": 0,
-		"compressNever":    0,
-		"dynamicAddr":      0,
-		"staticAddr":       0,
-	}
 	for _, cfg := range s.cfg.Devices() {
 		if cfg.Introducer {
-			deviceUses["introducer"]++
+			report.DeviceUses.Introducer++
 		}
 		if cfg.CertName != "" && cfg.CertName != "syncthing" {
-			deviceUses["customCertName"]++
+			report.DeviceUses.CustomCertName++
 		}
-		if cfg.Compression == protocol.CompressAlways {
-			deviceUses["compressAlways"]++
-		} else if cfg.Compression == protocol.CompressMetadata {
-			deviceUses["compressMetadata"]++
-		} else if cfg.Compression == protocol.CompressNever {
-			deviceUses["compressNever"]++
+		switch cfg.Compression {
+		case protocol.CompressAlways:
+			report.DeviceUses.CompressAlways++
+		case protocol.CompressMetadata:
+			report.DeviceUses.CompressMetadata++
+		case protocol.CompressNever:
+			report.DeviceUses.CompressNever++
+		default:
+			l.Warnf("Unhandled versioning type for usage reports: %s", cfg.Compression)
 		}
+
 		for _, addr := range cfg.Addresses {
 			if addr == "dynamic" {
-				deviceUses["dynamicAddr"]++
+				report.DeviceUses.DynamicAddr++
 			} else {
-				deviceUses["staticAddr"]++
+				report.DeviceUses.StaticAddr++
 			}
 		}
 	}
-	res["deviceUses"] = deviceUses
 
-	defaultAnnounceServersDNS, defaultAnnounceServersIP, otherAnnounceServers := 0, 0, 0
+	report.Announce.GlobalEnabled = opts.GlobalAnnEnabled
+	report.Announce.LocalEnabled = opts.LocalAnnEnabled
 	for _, addr := range opts.RawGlobalAnnServers {
 		if addr == "default" || addr == "default-v4" || addr == "default-v6" {
-			defaultAnnounceServersDNS++
+			report.Announce.DefaultServersDNS++
 		} else {
-			otherAnnounceServers++
+			report.Announce.OtherServers++
 		}
 	}
-	res["announce"] = map[string]interface{}{
-		"globalEnabled":     opts.GlobalAnnEnabled,
-		"localEnabled":      opts.LocalAnnEnabled,
-		"defaultServersDNS": defaultAnnounceServersDNS,
-		"defaultServersIP":  defaultAnnounceServersIP,
-		"otherServers":      otherAnnounceServers,
-	}
 
-	defaultRelayServers, otherRelayServers := 0, 0
+	report.Relays.Enabled = opts.RelaysEnabled
 	for _, addr := range s.cfg.Options().ListenAddresses() {
 		switch {
 		case addr == "dynamic+https://relays.syncthing.net/endpoint":
-			defaultRelayServers++
+			report.Relays.DefaultServers++
 		case strings.HasPrefix(addr, "relay://") || strings.HasPrefix(addr, "dynamic+http"):
-			otherRelayServers++
+			report.Relays.OtherServers++
+
 		}
 	}
-	res["relays"] = map[string]interface{}{
-		"enabled":        defaultRelayServers+otherAnnounceServers > 0,
-		"defaultServers": defaultRelayServers,
-		"otherServers":   otherRelayServers,
-	}
 
-	res["usesRateLimit"] = opts.MaxRecvKbps > 0 || opts.MaxSendKbps > 0
+	report.UsesRateLimit = opts.MaxRecvKbps > 0 || opts.MaxSendKbps > 0
+	report.UpgradeAllowedManual = !(upgrade.DisabledByCompilation || s.noUpgrade)
+	report.UpgradeAllowedAuto = !(upgrade.DisabledByCompilation || s.noUpgrade) && opts.AutoUpgradeIntervalH > 0
+	report.UpgradeAllowedPre = !(upgrade.DisabledByCompilation || s.noUpgrade) && opts.AutoUpgradeIntervalH > 0 && opts.UpgradeToPreReleases
 
-	res["upgradeAllowedManual"] = !(upgrade.DisabledByCompilation || s.noUpgrade)
-	res["upgradeAllowedAuto"] = !(upgrade.DisabledByCompilation || s.noUpgrade) && opts.AutoUpgradeIntervalH > 0
-	res["upgradeAllowedPre"] = !(upgrade.DisabledByCompilation || s.noUpgrade) && opts.AutoUpgradeIntervalH > 0 && opts.UpgradeToPreReleases
+	// V3
 
 	if urVersion >= 3 {
-		res["uptime"] = s.UptimeS()
-		res["natType"] = s.connectionsService.NATType()
-		res["alwaysLocalNets"] = len(opts.AlwaysLocalNets) > 0
-		res["cacheIgnoredFiles"] = opts.CacheIgnoredFiles
-		res["overwriteRemoteDeviceNames"] = opts.OverwriteRemoteDevNames
-		res["progressEmitterEnabled"] = opts.ProgressUpdateIntervalS > -1
-		res["customDefaultFolderPath"] = opts.DefaultFolderPath != "~"
-		res["customTrafficClass"] = opts.TrafficClass != 0
-		res["customTempIndexMinBlocks"] = opts.TempIndexMinBlocks != 10
-		res["temporariesDisabled"] = opts.KeepTemporariesH == 0
-		res["temporariesCustom"] = opts.KeepTemporariesH != 24
-		res["limitBandwidthInLan"] = opts.LimitBandwidthInLan
-		res["customReleaseURL"] = opts.ReleasesURL != "https://upgrades.syncthing.net/meta.json"
-		res["restartOnWakeup"] = opts.RestartOnWakeup
+		report.Uptime = s.UptimeS()
+		report.NATType = s.connectionsService.NATType()
+		report.AlwaysLocalNets = len(opts.AlwaysLocalNets) > 0
+		report.CacheIgnoredFiles = opts.CacheIgnoredFiles
+		report.OverwriteRemoteDeviceNames = opts.OverwriteRemoteDevNames
+		report.ProgressEmitterEnabled = opts.ProgressUpdateIntervalS > -1
+		report.CustomDefaultFolderPath = opts.DefaultFolderPath != "~"
+		report.CustomTrafficClass = opts.TrafficClass != 0
+		report.CustomTempIndexMinBlocks = opts.TempIndexMinBlocks != 10
+		report.TemporariesDisabled = opts.KeepTemporariesH == 0
+		report.TemporariesCustom = opts.KeepTemporariesH != 24
+		report.LimitBandwidthInLan = opts.LimitBandwidthInLan
+		report.CustomReleaseURL = opts.ReleasesURL != "https=//upgrades.syncthing.net/meta.json"
+		report.RestartOnWakeup = opts.RestartOnWakeup
+		report.CustomStunServers = len(opts.RawStunServers) != 1 || opts.RawStunServers[0] != "default"
 
-		folderUsesV3 := map[string]int{
-			"scanProgressDisabled":    0,
-			"conflictsDisabled":       0,
-			"conflictsUnlimited":      0,
-			"conflictsOther":          0,
-			"disableSparseFiles":      0,
-			"disableTempIndexes":      0,
-			"alwaysWeakHash":          0,
-			"customWeakHashThreshold": 0,
-			"fsWatcherEnabled":        0,
-		}
-		pullOrder := make(map[string]int)
-		filesystemType := make(map[string]int)
-		var fsWatcherDelays []int
 		for _, cfg := range s.cfg.Folders() {
 			if cfg.ScanProgressIntervalS < 0 {
-				folderUsesV3["scanProgressDisabled"]++
+				report.FolderUsesV3.ScanProgressDisabled++
 			}
 			if cfg.MaxConflicts == 0 {
-				folderUsesV3["conflictsDisabled"]++
+				report.FolderUsesV3.ConflictsDisabled++
 			} else if cfg.MaxConflicts < 0 {
-				folderUsesV3["conflictsUnlimited"]++
+				report.FolderUsesV3.ConflictsUnlimited++
 			} else {
-				folderUsesV3["conflictsOther"]++
+				report.FolderUsesV3.ConflictsOther++
 			}
 			if cfg.DisableSparseFiles {
-				folderUsesV3["disableSparseFiles"]++
+				report.FolderUsesV3.DisableSparseFiles++
 			}
 			if cfg.DisableTempIndexes {
-				folderUsesV3["disableTempIndexes"]++
+				report.FolderUsesV3.DisableTempIndexes++
 			}
 			if cfg.WeakHashThresholdPct < 0 {
-				folderUsesV3["alwaysWeakHash"]++
+				report.FolderUsesV3.AlwaysWeakHash++
 			} else if cfg.WeakHashThresholdPct != 25 {
-				folderUsesV3["customWeakHashThreshold"]++
+				report.FolderUsesV3.CustomWeakHashThreshold++
 			}
 			if cfg.FSWatcherEnabled {
-				folderUsesV3["fsWatcherEnabled"]++
+				report.FolderUsesV3.FsWatcherEnabled++
 			}
-			pullOrder[cfg.Order.String()]++
-			filesystemType[cfg.FilesystemType.String()]++
-			fsWatcherDelays = append(fsWatcherDelays, cfg.FSWatcherDelayS)
+			report.FolderUsesV3.PullOrder[cfg.Order.String()]++
+			report.FolderUsesV3.FilesystemType[cfg.FilesystemType.String()]++
+			report.FolderUsesV3.FsWatcherDelays = append(report.FolderUsesV3.FsWatcherDelays, cfg.FSWatcherDelayS)
 		}
-		sort.Ints(fsWatcherDelays)
-		folderUsesV3Interface := map[string]interface{}{
-			"pullOrder":       pullOrder,
-			"filesystemType":  filesystemType,
-			"fsWatcherDelays": fsWatcherDelays,
-		}
-		for key, value := range folderUsesV3 {
-			folderUsesV3Interface[key] = value
-		}
-		res["folderUsesV3"] = folderUsesV3Interface
+		sort.Ints(report.FolderUsesV3.FsWatcherDelays)
 
 		guiCfg := s.cfg.GUI()
 		// Anticipate multiple GUI configs in the future, hence store counts.
-		guiStats := map[string]int{
-			"enabled":                   0,
-			"useTLS":                    0,
-			"useAuth":                   0,
-			"insecureAdminAccess":       0,
-			"debugging":                 0,
-			"insecureSkipHostCheck":     0,
-			"insecureAllowFrameLoading": 0,
-			"listenLocal":               0,
-			"listenUnspecified":         0,
-		}
-		theme := make(map[string]int)
 		if guiCfg.Enabled {
-			guiStats["enabled"]++
+			report.GUIStats.Enabled++
 			if guiCfg.UseTLS() {
-				guiStats["useTLS"]++
+				report.GUIStats.UseTLS++
 			}
 			if len(guiCfg.User) > 0 && len(guiCfg.Password) > 0 {
-				guiStats["useAuth"]++
+				report.GUIStats.UseAuth++
 			}
 			if guiCfg.InsecureAdminAccess {
-				guiStats["insecureAdminAccess"]++
+				report.GUIStats.InsecureAdminAccess++
 			}
 			if guiCfg.Debugging {
-				guiStats["debugging"]++
+				report.GUIStats.Debugging++
 			}
 			if guiCfg.InsecureSkipHostCheck {
-				guiStats["insecureSkipHostCheck"]++
+				report.GUIStats.InsecureSkipHostCheck++
 			}
 			if guiCfg.InsecureAllowFrameLoading {
-				guiStats["insecureAllowFrameLoading"]++
+				report.GUIStats.InsecureAllowFrameLoading++
 			}
 
 			addr, err := net.ResolveTCPAddr("tcp", guiCfg.Address())
 			if err == nil {
 				if addr.IP.IsLoopback() {
-					guiStats["listenLocal"]++
+					report.GUIStats.ListenLocal++
+
 				} else if addr.IP.IsUnspecified() {
-					guiStats["listenUnspecified"]++
+					report.GUIStats.ListenUnspecified++
 				}
 			}
-
-			theme[guiCfg.Theme]++
+			report.GUIStats.Theme[guiCfg.Theme]++
 		}
-		guiStatsInterface := map[string]interface{}{
-			"theme": theme,
-		}
-		for key, value := range guiStats {
-			guiStatsInterface[key] = value
-		}
-		res["guiStats"] = guiStatsInterface
 	}
 
-	for key, value := range s.model.UsageReportingStats(urVersion, preview) {
-		res[key] = value
+	s.model.UsageReportingStats(report, urVersion, preview)
+
+	if err := report.ClearForVersion(urVersion); err != nil {
+		return nil, err
 	}
 
-	return res
+	return report, nil
 }
 
 func (s *Service) UptimeS() int {
@@ -369,7 +309,10 @@ func (s *Service) UptimeS() int {
 }
 
 func (s *Service) sendUsageReport(ctx context.Context) error {
-	d := s.ReportData(ctx)
+	d, err := s.ReportData(ctx)
+	if err != nil {
+		return err
+	}
 	var b bytes.Buffer
 	if err := json.NewEncoder(&b).Encode(d); err != nil {
 		return err
@@ -384,12 +327,11 @@ func (s *Service) sendUsageReport(ctx context.Context) error {
 			},
 		},
 	}
-	req, err := http.NewRequest("POST", s.cfg.Options().URURL, &b)
+	req, err := http.NewRequestWithContext(ctx, "POST", s.cfg.Options().URURL, &b)
 	if err != nil {
 		return err
 	}
 	req.Header.Set("Content-Type", "application/json")
-	req.Cancel = ctx.Done()
 	resp, err := client.Do(req)
 	if err != nil {
 		return err