Embed wing hash with package variables and templating

.gitignore

@@ -4,6 +4,7 @@
 /tarmak_darwin_amd64
 /tarmak_local_build
 /wing_linux_amd64
+/wing_linux_amd64_unversioned
 /dist/
 /bin/
 .DS_Store

Makefile

@@ -76,13 +76,17 @@ go_vet:
 
 go_build:
 	# make sure you add all binaries to the .goreleaser.yml as well
-	CGO_ENABLED=0 GOOS=linux  GOARCH=amd64 go build -tags netgo -ldflags '-w -X main.version=$(CI_COMMIT_TAG) -X main.commit=$(CI_COMMIT_SHA) -X main.date=$(shell date -u +%Y-%m-%dT%H:%M:%SZ)' -o tarmak_linux_amd64           ./cmd/tarmak
-	CGO_ENABLED=0 GOOS=darwin GOARCH=amd64 go build -tags netgo -ldflags '-w -X main.version=$(CI_COMMIT_TAG) -X main.commit=$(CI_COMMIT_SHA) -X main.date=$(shell date -u +%Y-%m-%dT%H:%M:%SZ)' -o tarmak_darwin_amd64          ./cmd/tarmak
+	# The hash of this binary is used to test if wing has changed in the s3 object etag
+	$(eval WING_HASH := $(shell md5sum wing_linux_amd64_unversioned | awk '{print $$1}'))
+	CGO_ENABLED=0 GOOS=linux  GOARCH=amd64 go build -tags netgo -ldflags '-w -X main.version=$(CI_COMMIT_TAG) -X main.commit=$(CI_COMMIT_SHA) -X main.date=$(shell date -u +%Y-%m-%dT%H:%M:%SZ) -X github.com/jetstack/tarmak/pkg/terraform.wingHash=$(WING_HASH) -X main.wingHash=$(WING_HASH)' -o tarmak_linux_amd64 ./cmd/tarmak
+	CGO_ENABLED=0 GOOS=darwin GOARCH=amd64 go build -tags netgo -ldflags '-w -X main.version=$(CI_COMMIT_TAG) -X main.commit=$(CI_COMMIT_SHA) -X main.date=$(shell date -u +%Y-%m-%dT%H:%M:%SZ) -X pkg/terraform/templating.wingHash=$$WING_HASH -X main.wingHash=$(WING_HASH)' -o tarmak_darwin_amd64 ./cmd/tarmak
 
-# wing is must come first as it's used in the go-bindata
+# wing binaries are used in the go-bindata
 go_build_wing:
-	# make sure you add all binaries to the .goreleaser.yml as well
-	CGO_ENABLED=0 GOOS=linux  GOARCH=amd64 go build -tags netgo -ldflags '-w -X main.version=$(CI_COMMIT_TAG) -X main.commit=$(CI_COMMIT_SHA) -X main.date=$(shell date -u +%Y-%m-%dT%H:%M:%SZ)' -o wing_linux_amd64             ./cmd/wing
+	# Build a version of the wing binary without build variables
+	CGO_ENABLED=0 GOOS=linux  GOARCH=amd64 go build -tags netgo -o wing_linux_amd64_unversioned ./cmd/wing
+	# Build a release wing binary
+	CGO_ENABLED=0 GOOS=linux  GOARCH=amd64 go build -tags netgo -ldflags '-w -X main.version=$(CI_COMMIT_TAG) -X main.commit=$(CI_COMMIT_SHA) -X main.date=$(shell date -u +%Y-%m-%dT%H:%M:%SZ)' -o wing_linux_amd64 ./cmd/wing
 
 $(BINDIR)/mockgen:
 	mkdir -p $(BINDIR)

cmd/tarmak/cmd/version.go

@@ -13,6 +13,7 @@ var Version struct {
 	Version   string
 	BuildDate string
 	Commit    string
+	WingHash  string
 }
 
 var AppName string = "tarmak"

cmd/tarmak/main.go

@@ -8,14 +8,16 @@ import (
 )
 
 var (
-	version string = "dev"
-	commit  string = "unknown"
-	date    string = ""
+	commit   string = "unknown"
+	date     string = ""
+	version  string = "dev"
+	wingHash string = "unknown"
 )
 
 func main() {
 	cmd.Version.Version = version
 	cmd.Version.Commit = commit
 	cmd.Version.BuildDate = date
+	cmd.Version.WingHash = wingHash
 	cmd.Execute(os.Args[1:])
 }

pkg/terraform/templating.go

@@ -20,7 +20,6 @@ import (
 )
 
 func (t *Terraform) GenerateCode(c interfaces.Cluster) (err error) {
-
 	terraformCodePath := t.codePath(c)
 	if err := utils.EnsureDirectory(
 		terraformCodePath,
@@ -96,6 +95,7 @@ func (t *Terraform) GenerateCode(c interfaces.Cluster) (err error) {
 		cluster:  c,
 		destDir:  terraformCodePath,
 		rootPath: rootPath,
+		wingHash: wingHash,
 	}
 	if err := templ.Generate(); err != nil {
 		return err
@@ -109,6 +109,7 @@ type terraformTemplate struct {
 	cluster  interfaces.Cluster
 	destDir  string
 	rootPath string
+	wingHash string
 }
 
 func (t *terraformTemplate) Generate() error {
@@ -137,6 +138,10 @@ func (t *terraformTemplate) Generate() error {
 	if err := t.generateTemplate("jenkins_elb", "modules/jenkins/jenkins_elb"); err != nil {
 		result = multierror.Append(result, err)
 	}
+	// TODO time for a loop over an array of pairs?
+	if err := t.generateTemplate("wing_s3", "modules/kubernetes/wing_s3"); err != nil {
+		result = multierror.Append(result, err)
+	}
 	if err := t.generateTerraformVariables(); err != nil {
 		result = multierror.Append(result, err)
 	}
@@ -171,6 +176,7 @@ func (t *terraformTemplate) data(module string) map[string]interface{} {
 		"JenkinsCertificateARN": jenkinsCertificateARN,
 		"JenkinsInstall":        jenkinsInstall,
 		"Module":                module,
+		"WingHash":              t.wingHash,
 	}
 }
 

pkg/terraform/terraform.go

@@ -26,6 +26,9 @@ import (
 
 const debugShell = "debug-shell"
 
+// wingHash is set by a linker flag to the hash of the lastest wing binary
+var wingHash string
+
 type Terraform struct {
 	*tarmakDocker.App
 	log    *logrus.Entry

terraform/amazon/templates/wing_s3.tf.template

@@ -0,0 +1,6 @@
+resource "aws_s3_bucket_object" "wing-binary" {
+  source = "wing_linux_amd64"
+  bucket = "${var.secrets_bucket}"
+  key    = "${data.template_file.stack_name.rendered}/wing-{{ .WingHash }}"
+  etag   = "{{ .WingHash }}"
+}