Add support for adding APT preferences

bootstrapvz/base/bootstrapinfo.py

@@ -83,6 +83,9 @@ class BootstrapInformation(object):
 		# so that tasks may add to that list without having to fiddle with apt source list files.
 		from pkg.sourceslist import SourceLists
 		self.source_lists = SourceLists(self.manifest_vars)
+		# Keep a list of apt preferences
+		from pkg.preferenceslist import PreferenceLists
+		self.preference_lists = PreferenceLists(self.manifest_vars)
 		# Keep a list of packages that should be installed, tasks can add and remove things from this list
 		from pkg.packagelist import PackageList
 		self.packages = PackageList(self.manifest_vars, self.source_lists)

bootstrapvz/base/manifest-schema.json

@@ -57,6 +57,33 @@
 					"additionalProperties": false,
 					"minItems": 1
 				},
+				"preferences": {
+					"type": "object",
+					"patternProperties": {
+						"^[^\/\\0]+$": {
+							"type": "array",
+							"items": {
+								"type": "object",
+								"properties": {
+									"pin": {
+										"type": "string"
+									},
+									"package": {
+										"type": "string"
+									},
+									"pin-priority": {
+										"type": "integer"
+									}
+								},
+								"required": ["pin", "package", "pin-priority"],
+								"additionalProperties": false
+							},
+							"minItems": 1
+						}
+					},
+					"additionalProperties": false,
+					"minItems": 1
+				},
 				"trusted-keys": {
 					"type": "array",
 					"items": { "$ref": "#/definitions/absolute_path" },

bootstrapvz/base/pkg/preferenceslist.py

@@ -0,0 +1,49 @@
+
+
+class PreferenceLists(object):
+	"""Represents a list of preferences lists for apt
+	"""
+
+	def __init__(self, manifest_vars):
+		"""
+		Args:
+			manifest_vars (dict): The manifest variables
+		"""
+		# A dictionary with the name of the file in preferences.d as the key
+		# That values are lists of Preference objects
+		self.preferences = {}
+		# Save the manifest variables, we need the later on
+		self.manifest_vars = manifest_vars
+
+	def add(self, name, preferences):
+		"""Adds a preference to the apt preferences list
+
+		Args:
+			name (str): Name of the file in preferences.list.d, may contain manifest vars references
+			preferences (object): The preferences
+		"""
+		name = name.format(**self.manifest_vars)
+                self.preferences[name] = [Preference(p) for p in preferences]
+
+
+class Preference(object):
+	"""Represents a single preference
+	"""
+
+	def __init__(self, preference):
+		"""
+		Args:
+			preference (dict): A apt preference dictionary
+
+		Raises:
+			PreferenceError
+		"""
+                self.preference = preference
+
+	def __str__(self):
+		"""Convert the object into a preference block
+
+		Returns:
+			string.
+		"""
+                return "Package: {package}\nPin: {pin}\nPin-Priority: {pin-priority}\n".format(**self.preference)

bootstrapvz/common/task_sets.py

@@ -63,6 +63,9 @@ def get_apt_set(manifest):
 		base.append(apt.AddManifestSources)
 	if 'trusted-keys' in manifest.packages:
 		base.append(apt.InstallTrustedKeys)
+	if 'preferences' in manifest.packages:
+		base.append(apt.AddManifestPreferences)
+		base.append(apt.WritePreferences)
 	if 'install' in manifest.packages:
 		base.append(packages.AddManifestPackages)
 	if manifest.packages.get('install_standard', False):

bootstrapvz/common/tasks/apt.py

@@ -33,6 +33,16 @@ class AddDefaultSources(Task):
 			info.source_lists.add('main', 'deb-src {apt_mirror} {system.release}-updates ' + sections)
 
 
+class AddManifestPreferences(Task):
+	description = 'Adding preferences from the manifest'
+	phase = phases.preparation
+
+	@classmethod
+	def run(cls, info):
+		for name, preferences in info.manifest.packages['preferences'].iteritems():
+                            info.preference_lists.add(name, preferences)
+
+
 class InstallTrustedKeys(Task):
 	description = 'Installing trusted keys'
 	phase = phases.package_installation
@@ -63,6 +73,23 @@ class WriteSources(Task):
 					source_list.write('{line}\n'.format(line=str(source)))
 
 
+class WritePreferences(Task):
+	description = 'Writing aptitude preferences to disk'
+	phase = phases.package_installation
+	predecessors = [WriteSources]
+
+	@classmethod
+	def run(cls, info):
+		for name, preferences in info.preference_lists.preferences.iteritems():
+			if name == 'main':
+				list_path = os.path.join(info.root, 'etc/apt/preferences')
+			else:
+				list_path = os.path.join(info.root, 'etc/apt/preferences.d/', name)
+			with open(list_path, 'w') as preference_list:
+				for preference in preferences:
+					preference_list.write('{preference}\n'.format(preference=str(preference)))
+
+
 class DisableDaemonAutostart(Task):
 	description = 'Disabling daemon autostart'
 	phase = phases.package_installation

docs/base/pkg.rst

@@ -15,6 +15,12 @@ Sources list
     :members:
     :private-members:
 
+Preferences list
+------------
+.. automodule:: bootstrapvz.base.pkg.preferenceslist
+    :members:
+    :private-members:
+
 Exceptions
 ----------
 .. automodule:: bootstrapvz.base.pkg.exceptions