cmd, docker: Updates for infrastructure

These are some changes to the relay pool server, upgrade server, and
crash receiver to run under Kubernetes. It's been in production for a
while.

cmd/stcrashreceiver/main.go

@@ -13,15 +13,17 @@
 package main
 
 import (
+	"context"
 	"encoding/json"
-	"flag"
 	"fmt"
 	"io"
 	"log"
 	"net/http"
 	"os"
 	"path/filepath"
+	"time"
 
+	"github.com/alecthomas/kong"
 	"github.com/syncthing/syncthing/lib/sha256"
 	"github.com/syncthing/syncthing/lib/ur"
 
@@ -30,26 +32,50 @@ import (
 
 const maxRequestSize = 1 << 20 // 1 MiB
 
+type cli struct {
+	Dir           string        `help:"Parent directory to store crash and failure reports in" env:"REPORTS_DIR" default:"."`
+	DSN           string        `help:"Sentry DSN" env:"SENTRY_DSN"`
+	Listen        string        `help:"HTTP listen address" default:":8080" env:"LISTEN_ADDRESS"`
+	MaxDiskFiles  int           `help:"Maximum number of reports on disk" default:"100000" env:"MAX_DISK_FILES"`
+	MaxDiskSizeMB int64         `help:"Maximum disk space to use for reports" default:"1024" env:"MAX_DISK_SIZE_MB"`
+	CleanInterval time.Duration `help:"Interval between cleaning up old reports" default:"12h" env:"CLEAN_INTERVAL"`
+	SentryQueue   int           `help:"Maximum number of reports to queue for sending to Sentry" default:"64" env:"SENTRY_QUEUE"`
+	DiskQueue     int           `help:"Maximum number of reports to queue for writing to disk" default:"64" env:"DISK_QUEUE"`
+}
+
 func main() {
-	dir := flag.String("dir", ".", "Parent directory to store crash and failure reports in")
-	dsn := flag.String("dsn", "", "Sentry DSN")
-	listen := flag.String("listen", ":22039", "HTTP listen address")
-	flag.Parse()
+	var params cli
+	kong.Parse(&params)
 
 	mux := http.NewServeMux()
 
-	cr := &crashReceiver{
-		dir: filepath.Join(*dir, "crash_reports"),
-		dsn: *dsn,
+	ds := &diskStore{
+		dir:      filepath.Join(params.Dir, "crash_reports"),
+		inbox:    make(chan diskEntry, params.DiskQueue),
+		maxFiles: params.MaxDiskFiles,
+		maxBytes: params.MaxDiskSizeMB << 20,
 	}
+	go ds.Serve(context.Background())
+
+	ss := &sentryService{
+		dsn:   params.DSN,
+		inbox: make(chan sentryRequest, params.SentryQueue),
+	}
+	go ss.Serve(context.Background())
+
+	cr := &crashReceiver{
+		store:  ds,
+		sentry: ss,
+	}
+
 	mux.Handle("/", cr)
 
-	if *dsn != "" {
-		mux.HandleFunc("/newcrash/failure", handleFailureFn(*dsn, filepath.Join(*dir, "failure_reports")))
+	if params.DSN != "" {
+		mux.HandleFunc("/newcrash/failure", handleFailureFn(params.DSN, filepath.Join(params.Dir, "failure_reports")))
 	}
 
 	log.SetOutput(os.Stdout)
-	if err := http.ListenAndServe(*listen, mux); err != nil {
+	if err := http.ListenAndServe(params.Listen, mux); err != nil {
 		log.Fatalln("HTTP serve:", err)
 	}
 }