Add Artifact and LocalArtifactCache classes.

An Artifact represents a thing that morph has built. An example would
be eglibc-runtime which morph may have built from the eglibc chunk
morphology. Another example would be a ready-to-use system image.

The LocalArtifactCache allows to store build artifacts in a local
directory. Users of this class can ask it whether it has a certain
artifact. They can also optain an I/O handle to read the artifact data
from.

In addition to just abstracting the way artifacts are stored,
LocalArtifactCache also allows to store and retrieve metadata for
(a) artifacts and (b) sources (the latter requires a cache key to
be provided to the LocalArtifactCache).

1 files changed, 135 insertions, 0 deletions

diff --git a/morphlib/localartifactcache_tests.py b/morphlib/localartifactcache_tests.py
new file mode 100644
index 00000000..41eb3d0b
--- /dev/null
+++ b/morphlib/localartifactcache_tests.py
@@ -0,0 +1,135 @@
+# Copyright (C) 2012  Codethink Limited
+# 
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; version 2 of the License.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+
+import unittest
+
+import morphlib
+
+
+class LocalArtifactCacheTests(unittest.TestCase):
+
+    def setUp(self):
+        self.tempdir = morphlib.tempdir.Tempdir()
+
+        morph = morphlib.morph2.Morphology(
+                '''
+                {
+                    "chunk": "chunk",
+                    "kind": "chunk",
+                    "artifacts": {
+                        "chunk-runtime": [
+                            "usr/bin",
+                            "usr/sbin",
+                            "usr/lib",
+                            "usr/libexec"
+                        ],
+                        "chunk-devel": [
+                            "usr/include"
+                        ]
+                    }
+                }
+                ''')
+        self.source = morphlib.source.Source(
+                'repo', 'ref', 'sha1', morph, 'chunk.morph')
+        self.runtime_artifact = morphlib.artifact.Artifact(
+                self.source, 'chunk-runtime', 'cachekey')
+        self.devel_artifact = morphlib.artifact.Artifact(
+                self.source, 'chunk-devel', 'cachekey')
+
+    def tearDown(self):
+        self.tempdir.remove()
+
+    def test_put_artifacts_and_check_whether_the_cache_has_them(self):
+        cache = morphlib.localartifactcache.LocalArtifactCache(
+                self.tempdir.dirname)
+
+        handle = cache.put(self.runtime_artifact)
+        handle.write('runtime')
+        handle.close()
+
+        self.assertTrue(cache.has(self.runtime_artifact))
+
+        handle = cache.put(self.devel_artifact)
+        handle.write('devel')
+        handle.close()
+
+        self.assertTrue(cache.has(self.runtime_artifact))
+        self.assertTrue(cache.has(self.devel_artifact))
+
+    def test_put_artifacts_and_get_them_afterwards(self):
+        cache = morphlib.localartifactcache.LocalArtifactCache(
+                self.tempdir.dirname)
+
+        handle = cache.put(self.runtime_artifact)
+        handle.write('runtime')
+        handle.close()
+
+        handle = cache.get(self.runtime_artifact)
+        stored_data = handle.read()
+        handle.close()
+
+        self.assertEqual(stored_data, 'runtime')
+
+        handle = cache.put(self.devel_artifact)
+        handle.write('devel')
+        handle.close()
+
+        handle = cache.get(self.runtime_artifact)
+        stored_data = handle.read()
+        handle.close()
+
+        self.assertEqual(stored_data, 'runtime')
+
+        handle = cache.get(self.devel_artifact)
+        stored_data = handle.read()
+        handle.close()
+
+        self.assertEqual(stored_data, 'devel')
+
+    def test_put_check_and_get_artifact_metadata(self):
+        cache = morphlib.localartifactcache.LocalArtifactCache(
+                self.tempdir.dirname)
+
+        handle = cache.put_artifact_metadata(self.runtime_artifact, 'log')
+        handle.write('log line 1\nlog line 2\n')
+        handle.close()
+
+        self.assertTrue(cache.has_artifact_metadata(
+            self.runtime_artifact, 'log'))
+
+        handle = cache.get_artifact_metadata(self.runtime_artifact, 'log')
+        stored_metadata = handle.read()
+        handle.close()
+
+        self.assertEqual(stored_metadata, 'log line 1\nlog line 2\n')
+
+    def test_put_check_and_get_source_metadata(self):
+        cache = morphlib.localartifactcache.LocalArtifactCache(
+                self.tempdir.dirname)
+
+        handle = cache.put_source_metadata(self.source, 'mycachekey', 'log')
+        handle.write('source log line 1\nsource log line 2\n')
+        handle.close()
+
+        self.assertTrue(cache.has_source_metadata(
+            self.source, 'mycachekey', 'log'))
+
+        handle = cache.get_source_metadata(self.source, 'mycachekey', 'log')
+        stored_metadata = handle.read()
+        handle.close()
+
+        self.assertEqual(stored_metadata,
+                         'source log line 1\nsource log line 2\n')