all: Remove usage of deprecated io/ioutil (#7971)

As of Go 1.16 io/ioutil is deprecated. This replaces usage with the
corresponding functions in package os and package io.

cmd/stcrashreceiver/main.go

@@ -17,7 +17,6 @@ import (
 	"flag"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"log"
 	"net/http"
 	"os"
@@ -58,7 +57,7 @@ func main() {
 func handleFailureFn(dsn, failureDir string) func(w http.ResponseWriter, req *http.Request) {
 	return func(w http.ResponseWriter, req *http.Request) {
 		lr := io.LimitReader(req.Body, maxRequestSize)
-		bs, err := ioutil.ReadAll(lr)
+		bs, err := io.ReadAll(lr)
 		req.Body.Close()
 		if err != nil {
 			http.Error(w, err.Error(), 500)

cmd/stcrashreceiver/sentry.go

@@ -9,7 +9,7 @@ package main
 import (
 	"bytes"
 	"errors"
-	"io/ioutil"
+	"io"
 	"regexp"
 	"strings"
 	"sync"
@@ -93,7 +93,7 @@ func parseCrashReport(path string, report []byte) (*raven.Packet, error) {
 	}
 
 	r := bytes.NewReader(report)
-	ctx, err := stack.ParseDump(r, ioutil.Discard, false)
+	ctx, err := stack.ParseDump(r, io.Discard, false)
 	if err != nil {
 		return nil, err
 	}

cmd/stcrashreceiver/sentry_test.go

@@ -8,7 +8,7 @@ package main
 
 import (
 	"fmt"
-	"io/ioutil"
+	"os"
 	"testing"
 )
 
@@ -59,7 +59,7 @@ func TestParseVersion(t *testing.T) {
 }
 
 func TestParseReport(t *testing.T) {
-	bs, err := ioutil.ReadFile("_testdata/panic.log")
+	bs, err := os.ReadFile("_testdata/panic.log")
 	if err != nil {
 		t.Fatal(err)
 	}

cmd/stcrashreceiver/sourcecodeloader.go

@@ -9,7 +9,7 @@ package main
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"path/filepath"
 	"strings"
@@ -80,7 +80,7 @@ func (l *githubSourceCodeLoader) Load(filename string, line, context int) ([][]b
 			fmt.Println("Loading source:", resp.Status)
 			return nil, 0
 		}
-		data, err := ioutil.ReadAll(resp.Body)
+		data, err := io.ReadAll(resp.Body)
 		_ = resp.Body.Close()
 		if err != nil {
 			fmt.Println("Loading source:", err.Error())

cmd/stcrashreceiver/stcrashreceiver.go

@@ -10,7 +10,6 @@ import (
 	"bytes"
 	"compress/gzip"
 	"io"
-	"io/ioutil"
 	"log"
 	"net/http"
 	"os"
@@ -96,7 +95,7 @@ func (r *crashReceiver) servePut(reportID, fullPath string, w http.ResponseWrite
 	// Read at most maxRequestSize of report data.
 	log.Println("Receiving report", reportID)
 	lr := io.LimitReader(req.Body, maxRequestSize)
-	bs, err := ioutil.ReadAll(lr)
+	bs, err := io.ReadAll(lr)
 	if err != nil {
 		log.Println("Reading report:", err)
 		http.Error(w, "Internal server error", http.StatusInternalServerError)
@@ -110,7 +109,7 @@ func (r *crashReceiver) servePut(reportID, fullPath string, w http.ResponseWrite
 	gw.Close()
 
 	// Create an output file with the compressed report
-	err = ioutil.WriteFile(fullPath, buf.Bytes(), 0644)
+	err = os.WriteFile(fullPath, buf.Bytes(), 0644)
 	if err != nil {
 		log.Println("Saving report:", err)
 		http.Error(w, "Internal server error", http.StatusInternalServerError)

cmd/stcrashreceiver/util.go

@@ -10,9 +10,9 @@ import (
 	"bytes"
 	"compress/gzip"
 	"fmt"
-	"io/ioutil"
 	"net"
 	"net/http"
+	"os"
 	"path/filepath"
 	"time"
 
@@ -53,5 +53,5 @@ func compressAndWrite(bs []byte, fullPath string) error {
 	gw.Close()
 
 	// Create an output file with the compressed report
-	return ioutil.WriteFile(fullPath, buf.Bytes(), 0644)
+	return os.WriteFile(fullPath, buf.Bytes(), 0644)
 }