Make r10edocker version more easily set (#10)

* Make r10edocker version more easily set

We make the version of `r10edocker` more easily overridable during
build, which reduces the amount of error-prone manual work to allow
better automation.

* Un-dockerignore the .git directory

We need to get the .git directory copied to Docker builder for the version info.

* Update release.yml

With the latest changes, released app version should always be identical
to the tagged version. Therefore, we update the version check failure
message as if it's an assert.

.dockerignore

@@ -2,5 +2,4 @@ r10e-docker/out/
 build/
 r10e-build/
 .github/
-.git/
 CODEOWNERS

.github/workflows/release.yml

@@ -36,7 +36,7 @@ jobs:
           cd ${{ github.workspace }}
           APP_VERSION="$(r10e-build/r10edocker-linux-amd64 --version | rev | cut -f1 -d' ' | rev)"
           if [ "$APP_VERSION" != "$RELEASE_VERSION" ]; then
-            echo "version (${APP_VERSION}) in version/version.go and tagged version (${RELEASE_VERSION}) mismatch"
+            echo "This is not supposed to happen. There must be a versioning bug."
             exit 1
           fi
 

Makefile

@@ -4,6 +4,7 @@ build_dir := $(mkfile_dir)/build
 r10e_build_dir := $(mkfile_dir)/r10e-build
 GOOS ?= $(shell go version | awk '{print $$NF}' | cut -d/ -f1)
 GOARCH ?= $(shell go version | awk '{print $$NF}' | cut -d/ -f2)
+VERSION ?= $(shell git describe --tags --dirty  --always)
 bin := $(build_dir)/r10edocker-$(GOOS)-$(GOARCH)
 # project_name must match that in config.json
 project_name := go-r10e-docker
@@ -15,7 +16,7 @@ all: build
 
 build:
 	mkdir -p $(build_dir)
-	CGO_ENABLED=0 go build -trimpath -o $(bin) $(mkfile_dir)
+	CGO_ENABLED=0 go build -trimpath -ldflags "-X main.version=$(VERSION)" -o $(bin) $(mkfile_dir)
 
 r10e-build: build
 	cp $(bin) $(build_dir)/r10edocker

cmd/r10e-docker/root.go

@@ -7,15 +7,13 @@ import (
 
 	"github.com/spf13/cobra"
 	r10edocker "github.com/syncom/r10edocker/pkg/r10e-docker"
-	"github.com/syncom/r10edocker/version"
 )
 
 var configFile string
 
 var rootCmd = &cobra.Command{
-	Use:     "r10edocker",
-	Version: version.Version,
-	Short:   "r10edocer - make minimum, reproducible Docker container for Go application",
+	Use:   "r10edocker",
+	Short: "r10edocer - make minimum, reproducible Docker container for Go application",
 	Long: `r10edocker creates a framework for making reproducible Docker container images
 
 Configure r10edocker in JSON.
@@ -34,7 +32,8 @@ The resulting Docker container is minimum, in that it contains only the applicat
 	},
 }
 
-func Execute() {
+func Execute(version string) {
+	rootCmd.Version = version
 	if err := rootCmd.Execute(); err != nil {
 		log.Fatalf("CLI error:, '%s'", err)
 	}

main.go

@@ -4,6 +4,8 @@ import (
 	r10edocker "github.com/syncom/r10edocker/cmd/r10e-docker"
 )
 
+var version = "development"
+
 func main() {
-	r10edocker.Execute()
+	r10edocker.Execute(version)
 }