From 60994914e95a2c48dbc6713a6e0724095e6780dd Mon Sep 17 00:00:00 2001
From: Andrew Cholakian <andrew@andrewvc.com>
Date: Thu, 26 Aug 2021 19:56:29 -0500
Subject: [PATCH] [elastic-agent] Fix docker tar.gz generation for complete
 image

This interpolates the `variant` into the format string for .tar.gz
docker artifacts. In also correctly handles the case where the format
string is used in contexts without variant present, such as darwin. We
still need an empty value for the templating language not to error.

Fixes https://github.com/elastic/beats/issues/27608
---
 dev-tools/mage/dockerbuilder.go | 7 ++++---
 dev-tools/mage/pkgtypes.go      | 6 ++++--
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/dev-tools/mage/dockerbuilder.go b/dev-tools/mage/dockerbuilder.go
index 0fba00b4e268..c1027e948375 100644
--- a/dev-tools/mage/dockerbuilder.go
+++ b/dev-tools/mage/dockerbuilder.go
@@ -86,7 +86,7 @@ func (b *dockerBuilder) Build() error {
 			return errors.Wrap(err, "failed to build docker")
 		}
 
-		if err := b.dockerSave(tag); err != nil {
+		if err := b.dockerSave(tag, variant); err != nil {
 			return errors.Wrap(err, "failed to save docker as artifact")
 		}
 	}
@@ -209,7 +209,7 @@ func (b *dockerBuilder) dockerBuild(variant string) (string, error) {
 	return taggedImageName, sh.Run("docker", "build", "-t", taggedImageName, b.buildDir)
 }
 
-func (b *dockerBuilder) dockerSave(tag string) error {
+func (b *dockerBuilder) dockerSave(tag string, variant string) error {
 	if _, err := os.Stat(distributionsDir); os.IsNotExist(err) {
 		err := os.MkdirAll(distributionsDir, 0750)
 		if err != nil {
@@ -220,7 +220,8 @@ func (b *dockerBuilder) dockerSave(tag string) error {
 	outputFile := b.OutputFile
 	if outputFile == "" {
 		outputTar, err := b.Expand(defaultBinaryName+".docker.tar.gz", map[string]interface{}{
-			"Name": b.imageName,
+			"Name":    b.imageName,
+			"Variant": variant,
 		})
 		if err != nil {
 			return err
diff --git a/dev-tools/mage/pkgtypes.go b/dev-tools/mage/pkgtypes.go
index 9a8ebc6d2ad3..3a011131501a 100644
--- a/dev-tools/mage/pkgtypes.go
+++ b/dev-tools/mage/pkgtypes.go
@@ -48,7 +48,7 @@ const (
 	packageStagingDir = "build/package"
 
 	// defaultBinaryName specifies the output file for zip and tar.gz.
-	defaultBinaryName = "{{.Name}}-{{.Version}}{{if .Snapshot}}-SNAPSHOT{{end}}{{if .OS}}-{{.OS}}{{end}}{{if .Arch}}-{{.Arch}}{{end}}"
+	defaultBinaryName = "{{.Name}}-{{if .Variant}}{{.Variant}}-{{end}}{{.Version}}{{if .Snapshot}}-SNAPSHOT{{end}}{{if .OS}}-{{.OS}}{{end}}{{if .Arch}}-{{.Arch}}{{end}}"
 )
 
 // PackageType defines the file format of the package (e.g. zip, rpm, etc).
@@ -329,8 +329,10 @@ func (s *PackageSpec) ExtraVar(key, value string) {
 
 // Expand expands a templated string using data from the spec.
 func (s PackageSpec) Expand(in string, args ...map[string]interface{}) (string, error) {
+	// Assign a default value for variant since it's not always passed in
 	return expandTemplate("inline", in, FuncMap,
-		EnvMap(append([]map[string]interface{}{s.evalContext, s.toMap()}, args...)...))
+
+		EnvMap(append([]map[string]interface{}{s.evalContext, {"Variant": ""}, s.toMap()}, args...)...))
 }
 
 // MustExpand expands a templated string using data from the spec. It panics if