feat: display dyndns version in discord username

And display release date when running dyndns --version

.github/workflows/release.yml

@@ -17,11 +17,11 @@ jobs:
         uses: actions/checkout@v2
       - name: Build binaries
         run: |
-          CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -tags release -o "dyndns-$(git describe --tags)-linux-amd64" -ldflags "-X main.Version=$(git describe --tags)"
-          CGO_ENABLED=0 GOOS=linux GOARCH=arm GOARM=6 go build -tags release -o "dyndns-$(git describe --tags)-linux-arm" -ldflags "-X main.Version=$(git describe --tags)"
-          CGO_ENABLED=0 GOOS=linux GOARCH=arm64 go build -tags release -o "dyndns-$(git describe --tags)-linux-arm64" -ldflags "-X main.Version=$(git describe --tags)"
-          CGO_ENABLED=0 GOOS=darwin GOARCH=amd64 go build -tags release -o "dyndns-$(git describe --tags)-darwin-amd64" -ldflags "-X main.Version=$(git describe --tags)"
-          CGO_ENABLED=0 GOOS=windows GOARCH=amd64 go build -tags release -o "dyndns-$(git describe --tags)-windows-amd64.exe" -ldflags "-X main.Version=$(git describe --tags)"
+          CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -tags release -o "dyndns-$(git describe --tags)-linux-amd64" -ldflags "-X 'github.com/mlcdf/dyndns/internal/build.Version=$(git describe --tags)' -X 'github.com/mlcdf/dyndns/internal/build.Time=$(date)'"
+          CGO_ENABLED=0 GOOS=linux GOARCH=arm GOARM=6 go build -tags release -o "dyndns-$(git describe --tags)-linux-arm" -ldflags "-X 'github.com/mlcdf/dyndns/internal/build.Version=$(git describe --tags)' -X 'github.com/mlcdf/dyndns/internal/build.Time=$(date)'"
+          CGO_ENABLED=0 GOOS=linux GOARCH=arm64 go build -tags release -o "dyndns-$(git describe --tags)-linux-arm64" -ldflags "-X 'github.com/mlcdf/dyndns/internal/build.Version=$(git describe --tags)' -X 'github.com/mlcdf/dyndns/internal/build.Time=$(date)'"
+          CGO_ENABLED=0 GOOS=darwin GOARCH=amd64 go build -tags release -o "dyndns-$(git describe --tags)-darwin-amd64" -ldflags "-X 'github.com/mlcdf/dyndns/internal/build.Version=$(git describe --tags)' -X 'github.com/mlcdf/dyndns/internal/build.Time=$(date)'"
+          CGO_ENABLED=0 GOOS=windows GOARCH=amd64 go build -tags release -o "dyndns-$(git describe --tags)-windows-amd64.exe" -ldflags "-X 'github.com/mlcdf/dyndns/internal/build.Version=$(git describe --tags)' -X 'github.com/mlcdf/dyndns/internal/build.Time=$(date)'"
       - name: Upload release artifacts
         uses: actions/github-script@v3
         with:

internal/build/build.go

@@ -0,0 +1,19 @@
+package build
+
+// Version is set at build time using -ldflags="-X 'github.com/mlcdf/dyndns/internal/build.Version=dyndns v1.0.0'
+var Version = "(devel)"
+
+// Time is set at build time using -ldflags="-X 'github.com/mlcdf/dyndns/internal/build.Time=$(date)'
+var Time string
+
+func Short() string {
+	return "dyndns " + Version
+}
+
+func Long() string {
+	info := Short()
+	if Time != "" {
+		info = info + " (release date: " + Time + ")"
+	}
+	return info
+}

internal/discord/discord.go

@@ -8,6 +8,8 @@ import (
 	"net/http"
 	"os"
 	"time"
+
+	"github.com/mlcdf/dyndns/internal/build"
 )
 
 type Client struct {
@@ -86,6 +88,7 @@ func (c *Client) PostSuccess(webhook *Webhook) error {
 func (c *Client) Post(webhook *Webhook) error {
 	webhook.Embeds[0].TimeStamp = time.Now().UTC().Format(time.RFC3339)
 	webhook.Embeds[0].Footer.Text = hostname
+	webhook.Username = build.Short()
 
 	payload, err := json.Marshal(webhook)
 	if err != nil {

main.go

@@ -6,8 +6,8 @@ import (
 	"io"
 	"log"
 	"os"
-	"runtime/debug"
 
+	"github.com/mlcdf/dyndns/internal/build"
 	"github.com/mlcdf/dyndns/internal/discord"
 	"github.com/mlcdf/dyndns/internal/dyndns"
 	"github.com/mlcdf/dyndns/internal/gandi"
@@ -31,11 +31,6 @@ How to create a Discord webhook: https://support.discord.com/hc/en-us/articles/2
 How to generate your Gandi token: https://docs.gandi.net/en/domain_names/advanced_users/api.html
 `
 
-// Version can be set at link time to override debug.BuildInfo.Main.Version,
-// which is "(devel)" when building from within the module. See
-// golang.org/issue/29814 and golang.org/issue/29228.
-var Version string
-
 func main() {
 	log.SetFlags(0)
 	flag.Usage = func() { fmt.Fprint(os.Stderr, usage) }
@@ -65,15 +60,7 @@ func main() {
 	flag.Parse()
 
 	if versionFlag {
-		if Version != "" {
-			fmt.Println(Version)
-			return
-		}
-		if buildInfo, ok := debug.ReadBuildInfo(); ok {
-			fmt.Println(buildInfo.Main.Version)
-			return
-		}
-		fmt.Println("(unknown)")
+		fmt.Println(build.Long())
 		return
 	}