docker: Fix dockerfile creation

bootstrapvz/providers/docker/README.rst

@@ -26,8 +26,8 @@ Name
 Provider
 ~~~~~~~~
 
--  ``dockerfile``: Inline dockerfile that should be appended to
-   the one created by the bootstrapper.
+-  ``dockerfile``: List of Dockerfile instructions that should be appended to
+   the ones created by the bootstrapper.
    ``optional``
 
 -  ``labels``: Labels that should be added to the dockerfile.
@@ -49,8 +49,8 @@ Example:
     name: bootstrap-vz:latest
     provider:
       name: docker
-      dockerfile: >
-        CMD /bin/bash
+      dockerfile:
+        - CMD /bin/bash
       labels:
         name: debian-{system.release}-{system.architecture}-{%y}{%m}{%d}
         description: Debian {system.release} {system.architecture}

bootstrapvz/providers/docker/manifest-schema.yml

@@ -20,7 +20,11 @@ properties:
           patternProperties:
             ^.+$: {type: string}
       dockerfile:
-        type: string
+        type: array
+        items:
+          # https://github.com/turtlebender/docker/blob/6e2662b3bad319679e17fe25d410f246820ab0e9/builder/job.go#L27
+          type: string
+          pattern: '^(ENTRYPOINT|CMD|USER|WORKDIR|ENV|VOLUME|EXPOSE|ONBUILD|LABEL|MAINTAINER)'
   system:
     type: object
     properties:

bootstrapvz/providers/docker/tasks/image.py

@@ -9,7 +9,7 @@ class CreateDockerfileEntry(Task):
 
     @classmethod
     def run(cls, info):
-        info._docker['dockerfile'] = ''
+        info._docker['dockerfile'] = []
 
 
 class CreateImage(Task):
@@ -21,8 +21,10 @@ class CreateImage(Task):
         from pipes import quote
         tar_cmd = ['tar', '--create', '--numeric-owner',
                    '--directory', info.volume.path, '.']
-        docker_cmd = ['docker', 'import', '--change', info._docker['dockerfile'], '-',
-                      info.manifest.name.format(**info.manifest_vars)]
+        docker_cmd = ['docker', 'import']
+        for instruction in info._docker['dockerfile']:
+            docker_cmd.extend(['--change', instruction])
+        docker_cmd.extend(['-', info.manifest.name.format(**info.manifest_vars)])
         cmd = ' '.join(map(quote, tar_cmd)) + ' | ' + ' '.join(map(quote, docker_cmd))
         [info._docker['image_id']] = log_check_call([cmd], shell=True)
 
@@ -55,9 +57,8 @@ class PopulateLabels(Task):
             value = value.replace('\n', '\\\n')
             value = '"' + value + '"'
             return value
-        kv_pairs = [label + '=' + escape(value) for label, value in labels.items()]
-        # Add some nice newlines and indentation
-        info._docker['dockerfile'] += 'LABEL ' + ' \\\n      '.join(kv_pairs) + '\n'
+        for label, value in labels.items():
+            info._docker['dockerfile'].append('LABEL {}={}'.format(label, escape(value)))
 
 
 class AppendManifestDockerfile(Task):
@@ -68,4 +69,4 @@ class AppendManifestDockerfile(Task):
 
     @classmethod
     def run(cls, info):
-        info._docker['dockerfile'] += info.manifest.provider['dockerfile'] + '\n'
+        info._docker['dockerfile'].extend(info.manifest.provider['dockerfile'])

manifests/examples/docker/jessie-minimized.yml

@@ -4,8 +4,8 @@ provider:
   name: docker
   labels:
     description: Debian {system.release} {system.architecture}
-  dockerfile: >
-    CMD /bin/bash
+  dockerfile:
+    - CMD /bin/bash
 bootstrapper:
   workspace: /target
   variant: minbase