RemoteArtifactCache: Support multiple cache methods

This commit updates RemoteArtifactCache to enable it to interact with
a remote OSTree artifact cache.

Change-Id: Icdb2d3071adb6532e54ab7f203c391b3a30a1c63

1 files changed, 25 insertions, 0 deletions

diff --git a/morphlib/remoteartifactcache.py b/morphlib/remoteartifactcache.py
index 427e4cbb..f5115cd6 100644
--- a/morphlib/remoteartifactcache.py
+++ b/morphlib/remoteartifactcache.py
@@ -57,6 +57,18 @@ class RemoteArtifactCache(object):
 
     def __init__(self, server_url):
         self.server_url = server_url
+        self.name = urlparse.urlparse(server_url).hostname
+        try:
+            self.method = self._get_method()
+        except urllib2.URLError:
+            self.method = 'tarball'
+        except Exception as e: # pragma: no cover
+            logging.debug('Failed to determine cache method: %s' % e)
+            raise cliapp.AppException('Failed to determine method used by '
+                                      'remote cache.')
+        if self.method == 'ostree': # pragma: no cover
+            self.ostree_url = 'http://%s:%s/' % (self.name,
+                                                 self._get_ostree_info())
 
     def has(self, artifact):
         return self._has_file(artifact.basename())
@@ -112,5 +124,18 @@ class RemoteArtifactCache(object):
             server_url, '/1.0/artifacts?filename=%s' % 
             urllib.quote(filename))
 
+    def _get_method(self): # pragma: no cover
+        logging.debug('Getting cache method of %s' % self.server_url)
+        request_url = urlparse.urljoin(self.server_url, '/1.0/method')
+        req = urllib2.urlopen(request_url)
+        return req.read()
+
+    def _get_ostree_info(self): # pragma: no cover
+        logging.debug('Getting OSTree repo info.')
+        request_url = urlparse.urljoin(self.server_url, '/1.0/ostreeinfo')
+        logging.debug('sending %s' % request_url)
+        req = urllib2.urlopen(request_url)
+        return req.read()
+
     def __str__(self):  # pragma: no cover
         return self.server_url