Enable docker containers to be built with Git Sha

Author: frankywahl

.dockerignore

@@ -0,0 +1 @@
+.git/

Dockerfile

@@ -1,10 +1,11 @@
 FROM golang:latest AS builder
+ARG GIT_REVISION
 WORKDIR /app
 COPY go.sum .
 COPY go.mod .
 RUN go mod download
 COPY . .
-RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -o server cmd/web/web.go 
+RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -ldflags "-X github.com/go-franky/plain_http/version.GitRevision=$GIT_REVISION" -o server cmd/web/web.go
 
 FROM alpine
 RUN apk --no-cache add ca-certificates curl

Makefile

@@ -35,4 +35,7 @@ windows:
 	GOOS=windows GOARCH=${GOARCH} go build ${LDFLAGS} -o ${BINARY}-windows-${GOARCH}.exe cmd/web/web.go ; \
 	cd - >/dev/null
 
-.PHONY: default linux darwin windows test vet fmt clean
+docker:
+	docker build -t plain_http --build-arg GIT_REVISION=${COMMIT} .
+
+.PHONY: default linux darwin windows test vet fmt clean docker

docker-compose.yml

@@ -1,6 +1,9 @@
 version: "3.7"
 services:
   app:
-    build: .
+    build:
+      context: .
+      args:
+        GIT_REVISION: ''
     ports:
       - 8080:8080