upgrade deps; rewrite smtp session

vendor/github.com/getsentry/sentry-go/util.go

@@ -6,6 +6,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"os"
+	"runtime/debug"
 	"strings"
 	"time"
 
@@ -35,7 +36,7 @@ func monotonicTimeSince(start time.Time) (end time.Time) {
 	return start.Add(time.Since(start))
 }
 
-//nolint: deadcode, unused
+// nolint: deadcode, unused
 func prettyPrint(data interface{}) {
 	dbg, _ := json.MarshalIndent(data, "", "  ")
 	fmt.Println(string(dbg))
@@ -66,26 +67,48 @@ func defaultRelease() (release string) {
 		}
 	}
 
+	if info, ok := debug.ReadBuildInfo(); ok {
+		buildInfoVcsRevision := revisionFromBuildInfo(info)
+		if len(buildInfoVcsRevision) > 0 {
+			return buildInfoVcsRevision
+		}
+	}
+
 	// Derive a version string from Git. Example outputs:
 	// 	v1.0.1-0-g9de4
 	// 	v2.0-8-g77df-dirty
 	// 	4f72d7
-	cmd := exec.Command("git", "describe", "--long", "--always", "--dirty")
-	b, err := cmd.Output()
-	if err != nil {
-		// Either Git is not available or the current directory is not a
-		// Git repository.
-		var s strings.Builder
-		fmt.Fprintf(&s, "Release detection failed: %v", err)
-		if err, ok := err.(*exec.ExitError); ok && len(err.Stderr) > 0 {
-			fmt.Fprintf(&s, ": %s", err.Stderr)
+	if _, err := exec.LookPath("git"); err == nil {
+		cmd := exec.Command("git", "describe", "--long", "--always", "--dirty")
+		b, err := cmd.Output()
+		if err != nil {
+			// Either Git is not available or the current directory is not a
+			// Git repository.
+			var s strings.Builder
+			fmt.Fprintf(&s, "Release detection failed: %v", err)
+			if err, ok := err.(*exec.ExitError); ok && len(err.Stderr) > 0 {
+				fmt.Fprintf(&s, ": %s", err.Stderr)
+			}
+			Logger.Print(s.String())
+		} else {
+			release = strings.TrimSpace(string(b))
+			Logger.Printf("Using release from Git: %s", release)
+			return release
 		}
-		Logger.Print(s.String())
-		Logger.Print("Some Sentry features will not be available. See https://docs.sentry.io/product/releases/.")
-		Logger.Print("To stop seeing this message, pass a Release to sentry.Init or set the SENTRY_RELEASE environment variable.")
-		return ""
 	}
-	release = strings.TrimSpace(string(b))
-	Logger.Printf("Using release from Git: %s", release)
-	return release
+
+	Logger.Print("Some Sentry features will not be available. See https://docs.sentry.io/product/releases/.")
+	Logger.Print("To stop seeing this message, pass a Release to sentry.Init or set the SENTRY_RELEASE environment variable.")
+	return ""
+}
+
+func revisionFromBuildInfo(info *debug.BuildInfo) string {
+	for _, setting := range info.Settings {
+		if setting.Key == "vcs.revision" && setting.Value != "" {
+			Logger.Printf("Using release from debug info: %s", setting.Value)
+			return setting.Value
+		}
+	}
+
+	return ""
 }