Introduce docker build

.github/workflows/build.yml

@@ -1,6 +1,12 @@
 name: Build
 
-on: [push]
+on:
+  push:
+    branches:
+      - master
+
+env:
+  go_version: 1.21
 
 jobs:
   build:
@@ -9,14 +15,27 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Setup Go 1.21
+      - name: Setup Go ${{ env.go_version }}
         uses: actions/setup-go@v4
         with:
-          go-version: 1.21
+          go-version: ${{ env.go_version }}
           cache-dependency-path: go.sum
 
       - name: Install dependencies
         run: go get .
 
       - name: Build
         run: go build ./...
+
+      - name: Log in to the Container registry
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Build and push
+        uses: docker/build-push-action@v5
+        with:
+          push: true
+          tags: ghcr.io/${{ github.repository }}:latest

Dockerfile

@@ -0,0 +1,21 @@
+# syntax=docker/dockerfile:1
+
+FROM golang:1.21 AS builder
+
+COPY . /build
+WORKDIR /build
+RUN go mod download
+
+RUN GOOS=linux GOARCH=amd64 CGO_ENABLED=0 \
+    go build \
+    -trimpath \
+    -ldflags="-w -s" \
+    -o app \
+    main.go
+
+FROM scratch
+
+COPY --from=builder /build/app /root/app
+
+ENTRYPOINT ["/root/app"]
+EXPOSE 8080

main.go

@@ -20,7 +20,7 @@ func main() {
 	viper.AutomaticEnv()
 	viper.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
 
-	viper.SetDefault("http.host", "localhost")
+	viper.SetDefault("http.host", "0.0.0.0")
 	viper.SetDefault("http.port", 8080)
 
 	viper.SetDefault("mysql.user", "root")