feat: show application version in logs at startup (#118)

.github/workflows/build.yaml

@@ -42,6 +42,8 @@ jobs:
         with:
           context: .
           provenance: false
+          args: |
+            APP_VERSION=${{ github.ref_name }}
           push: ${{ github.event_name != 'pull_request' }}
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}

Dockerfile

@@ -1,6 +1,8 @@
 # syntax=docker/dockerfile:1@sha256:fe40cf4e92cd0c467be2cfc30657a680ae2398318afd50b0c80585784c604f28
 FROM golang:1.23.0@sha256:613a108a4a4b1dfb6923305db791a19d088f77632317cfc3446825c54fb862cd AS build-stage
 
+ARG APP_VERSION=dev
+
 # Set destination for COPY
 WORKDIR /app
 
@@ -24,7 +26,7 @@ ENV GOCACHE=/root/.cache/go-build \
 RUN --mount=type=cache,target=/go/pkg/mod/ \
     --mount=type=cache,target="/root/.cache/go-build" \
     --mount=type=bind,target=. \
-    go build -ldflags="-s -w" -o / ./...
+    go build -ldflags="-s -w -X main.Version=${APP_VERSION}" -o / ./...
 
 FROM gcr.io/distroless/base-debian12@sha256:1aae189e3baecbb4044c648d356ddb75025b2ba8d14cdc9c2a19ba784c90bfb9 AS build-release-stage
 

cmd/doco-cd/main.go

@@ -17,7 +17,10 @@ const (
 	healthPath  = "/v1/health"
 )
 
-var errMsg string
+var (
+	Version string
+	errMsg  string
+)
 
 func main() {
 	// Set default log level to debug
@@ -38,7 +41,7 @@ func main() {
 	// Set the actual log level
 	log = logger.New(logLevel)
 
-	log.Info("starting application", slog.String("log_level", c.LogLevel))
+	log.Info("starting application", slog.String("version", Version), slog.String("log_level", c.LogLevel))
 
 	// Test/verify the connection to the docker socket
 	err = docker.VerifySocketConnection(c.DockerAPIVersion)

dev.compose.yaml

@@ -1,7 +1,11 @@
 services:
   app:
     container_name: doco-cd
-    build: .
+    build:
+      context: .
+      dockerfile: Dockerfile
+      args:
+        - APP_VERSION=dev
     restart: no
     ports:
       - "80:80"
@@ -16,6 +20,6 @@ services:
     # Use `user: root` to run the app as root, or use `group_add` to use the non-root user and add the docker group id to it
     #user: root
     group_add:
-      - "971"  # change to the docker group id shown in the app error logs or in the output of `ls -l /var/run/docker.sock`
+      - "0"  # change to the docker group id shown in the app error logs or in the output of `ls -l /var/run/docker.sock`
     volumes:
       - /var/run/docker.sock:/var/run/docker.sock