Merge pull request #7127 from ladar/master

Added change support to docker-import post processor.

builder/docker/driver.go

@@ -20,7 +20,7 @@ type Driver interface {
 	Export(id string, dst io.Writer) error
 
 	// Import imports a container from a tar file
-	Import(path, repo string) (string, error)
+	Import(path string, changes []string, repo string) (string, error)
 
 	// IPAddress returns the address of the container that can be used
 	// for external access.

builder/docker/driver_docker.go

@@ -97,12 +97,23 @@ func (d *DockerDriver) Export(id string, dst io.Writer) error {
 	return nil
 }
 
-func (d *DockerDriver) Import(path string, repo string) (string, error) {
+func (d *DockerDriver) Import(path string, changes []string, repo string) (string, error) {
 	var stdout, stderr bytes.Buffer
-	cmd := exec.Command("docker", "import", "-", repo)
+
+	args := []string{"import"}
+
+	for _, change := range changes {
+		args = append(args, "--change", change)
+	}
+
+	args = append(args, "-")
+	args = append(args, repo)
+
+	cmd := exec.Command("docker", args...)
 	cmd.Stdout = &stdout
 	cmd.Stderr = &stderr
 	stdin, err := cmd.StdinPipe()
+
 	if err != nil {
 		return "", err
 	}
@@ -114,6 +125,8 @@ func (d *DockerDriver) Import(path string, repo string) (string, error) {
 	}
 	defer file.Close()
 
+	log.Printf("Importing tarball with args: %v", args)
+
 	if err := cmd.Start(); err != nil {
 		return "", err
 	}

builder/docker/driver_mock.go

@@ -101,7 +101,7 @@ func (d *MockDriver) Export(id string, dst io.Writer) error {
 	return d.ExportError
 }
 
-func (d *MockDriver) Import(path, repo string) (string, error) {
+func (d *MockDriver) Import(path string, changes []string, repo string) (string, error) {
 	d.ImportCalled = true
 	d.ImportPath = path
 	d.ImportRepo = repo

post-processor/docker-import/post-processor.go

@@ -16,8 +16,9 @@ const BuilderId = "packer.post-processor.docker-import"
 type Config struct {
 	common.PackerConfig `mapstructure:",squash"`
 
-	Repository string `mapstructure:"repository"`
-	Tag        string `mapstructure:"tag"`
+	Repository string   `mapstructure:"repository"`
+	Tag        string   `mapstructure:"tag"`
+	Changes    []string `mapstructure:"changes"`
 
 	ctx interpolate.Context
 }
@@ -62,7 +63,7 @@ func (p *PostProcessor) PostProcess(ui packer.Ui, artifact packer.Artifact) (pac
 
 	ui.Message("Importing image: " + artifact.Id())
 	ui.Message("Repository: " + importRepo)
-	id, err := driver.Import(artifact.Files()[0], importRepo)
+	id, err := driver.Import(artifact.Files()[0], p.config.Changes, importRepo)
 	if err != nil {
 		return nil, false, err
 	}

website/source/docs/post-processors/docker-import.html.md

@@ -25,11 +25,20 @@ registry.
 The configuration for this post-processor only requires a `repository`, a `tag`
 is optional.
 
+### Required:
+
 -   `repository` (string) - The repository of the imported image.
 
 -   `tag` (string) - The tag for the imported image. By default this is not
     set.
 
+### Optional:
+
+-   `changes` (array of strings) - Dockerfile instructions to add to the
+    commit. Example of instructions are `CMD`, `ENTRYPOINT`, `ENV`, and
+    `EXPOSE`. Example: `[ "USER ubuntu", "WORKDIR /app", "EXPOSE 8080" ]`
+
+
 ## Example
 
 An example is shown below, showing only the post-processor configuration:
@@ -48,3 +57,68 @@ into the local Docker process with a name of `hashicorp/packer:0.7`.
 Following this, you can use the
 [docker-push](/docs/post-processors/docker-push.html) post-processor to push it
 to a registry, if you want.
+
+## Changing Metadata
+
+Below is an example using the changes argument of the post-processor. This
+feature allows the tarball metadata to be changed when imported into the
+Docker environment. It is derived from the `docker import --change` command
+line [option to
+Docker](https://docs.docker.com/engine/reference/commandline/import/).
+
+Example uses of all of the options, assuming one is building an NGINX image
+from ubuntu as an simple example:
+
+``` json
+{
+  "type": "docker-import",
+  "repository": "local/centos6",
+  "tag": "latest",
+  "changes": [
+    "USER www-data",
+    "WORKDIR /var/www",
+    "ENV HOSTNAME www.example.com",
+    "VOLUME /test1 /test2",
+    "EXPOSE 80 443",
+    "LABEL version=1.0",
+    "ONBUILD RUN date",
+    "CMD [\"nginx\", \"-g\", \"daemon off;\"]",
+    "ENTRYPOINT /var/www/start.sh"
+  ]
+}
+```
+
+Allowed metadata fields that can be changed are:
+
+-   CMD
+    -   String, supports both array (escaped) and string form
+    -   EX: `"CMD [\"nginx\", \"-g\", \"daemon off;\"]"`
+    -   EX: `"CMD nginx -g daemon off;"`
+-   ENTRYPOINT
+    -   String
+    -   EX: `"ENTRYPOINT /var/www/start.sh"`
+-   ENV
+    -   String, note there is no equal sign:
+    -   EX: `"ENV HOSTNAME www.example.com"` not
+        `"ENV HOSTNAME=www.example.com"`
+-   EXPOSE
+    -   String, space separated ports
+    -   EX: `"EXPOSE 80 443"`
+-   LABEL
+    -   String, space separated key=value pairs
+    -   EX: `"LABEL version=1.0"`
+-   ONBUILD
+    -   String
+    -   EX: `"ONBUILD RUN date"`
+-   MAINTAINER
+    -   String, deprecated in Docker version 1.13.0
+    -   EX: `"MAINTAINER NAME"`
+-   USER
+    -   String
+    -   EX: `"USER USERNAME"`
+-   VOLUME
+    -   String
+    -   EX: `"VOLUME FROM TO"`
+-   WORKDIR
+    -   String
+    -   EX: `"WORKDIR PATH"`