Add 'debconf' plugin

Closes #282

bootstrapvz/plugins/debconf/__init__.py

@@ -0,0 +1,13 @@
+def validate_manifest(data, validator, error):
+    from bootstrapvz.common.tools import log_check_call
+    import os.path
+    schema_path = os.path.join(os.path.dirname(__file__),
+                               'schema.yaml')
+    validator(data, schema_path)
+    log_check_call(['debconf-set-selections', '--checkonly'],
+                   stdin=data['plugins']['debconf'])
+
+
+def resolve_tasks(taskset, manifest):
+    import tasks
+    taskset.update([tasks.DebconfSetSelections])

bootstrapvz/plugins/debconf/schema.yaml

@@ -0,0 +1,14 @@
+$schema: http://json-schema.org/schema#
+title: Manifest schema for the debconf plugin
+type: object
+properties:
+  plugins:
+    type: object
+    properties:
+      debconf:
+        name: Debconf selections to set
+        description: >-
+          This value should be an inline string in the
+          input format of debconf-set-selections(1).
+        type: string
+    required: [debconf]

bootstrapvz/plugins/debconf/tasks.py

@@ -0,0 +1,15 @@
+from bootstrapvz.base import Task
+from bootstrapvz.common import phases
+from bootstrapvz.common.tasks import packages
+from bootstrapvz.common.tools import log_check_call
+
+
+class DebconfSetSelections(Task):
+    description = 'Set debconf(7) selections from the manifest'
+    phase = phases.package_installation
+    successors = [packages.InstallPackages]
+
+    @classmethod
+    def run(cls, info):
+        log_check_call(['chroot', info.root, 'debconf-set-selections'],
+                       stdin=info.manifest.plugins['debconf'])