Add generic way to force a specific chunk version in a system-branch

The old set_lighttpd_chunk_version() function is no longer needed.

1 files changed, 72 insertions, 16 deletions

diff --git a/test_trove_upgrades.py b/test_trove_upgrades.py
index f90cbb9..75580e2 100644
--- a/test_trove_upgrades.py
+++ b/test_trove_upgrades.py
@@ -58,6 +58,11 @@ import time
 import urlparse
 import yaml
 
+# In general, tests should treat Morph as a black box rather than calling
+# functions in morphlib to do stuff. It's better than copying and pasting
+# stuff though!
+import morphlib
+import morphlib.plugins.branch_and_merge_plugin
 
 # The test host must have passwordless access to this machine. The tests set
 # set StrictHostKeyChecking=no for SSH connections so it does not need to be in
@@ -360,12 +365,63 @@ class TroveUpgrade(Deployment):
 
 
 class SystemTestBranch(object):
+    '''Morph system-branch abstraction for use in Baserock system tests.'''
     def __init__(self, workspace_dir, name):
         self.workspace_dir = workspace_dir
         self.branch_dir = os.path.join(workspace_dir, name)
         self.morphs_dir = os.path.join(
                 self.branch_dir, 'baserock:baserock', 'morphs')
 
+    def get_repo_and_ref_for_chunk(self, stratum, chunk):
+        stratum_morph_file = os.path.join(
+                self.morphs_dir, '%s.morph' % stratum)
+        stratum_morph = yaml.load(read_file(stratum_morph_file))
+
+        for chunkref in stratum_morph['chunks']:
+            if chunkref['name'] == chunk:
+                return chunkref['repo'], chunkref['ref']
+        else:
+            raise Exception(
+                    "Chunk %s not found in stratum %s" % (chunk, stratum))
+
+    def _copy_chunk_morph_if_missing(self, chunk_dir, chunk, original_ref):
+        chunk_morph_name = '%s.morph' % chunk
+        with set_directory(chunk_dir):
+            if os.path.exists(chunk_morph_name):
+                return
+            output = run_git(['ls-tree', original_ref, chunk_morph_name])
+            original_ref_has_chunk_morph = (len(output) > 0)
+            if not original_ref_has_chunk_morph:
+                return
+            object_name = original_ref + ':' + chunk_morph_name
+            with open(chunk_morph_name, 'w') as f:
+                run_git(['cat-file', 'blob', object_name], stdout=f)
+            message = 'Add lighttpd.morph from branch %s' % BRANCH
+            run_git(['add', chunk_morph_name])
+            run_git(['commit', '-m', message])
+
+    def set_chunk_version(self, system, stratum, chunk,
+                          tag='baserock/morph'):
+        '''
+        Force a specific version of a chunk to be built in a system self.
+
+        Uses `morph edit` and `git reset` to achieve this.
+        '''
+        chunk_repo_uri, original_ref = self.get_repo_and_ref_for_chunk(
+                branch, stratum, chunk)
+
+        with set_directory(self.morphs_dir):
+            run_morph(['edit', system, stratum, chunk])
+            run_git(['add', '%s.morph' % stratum])
+            run_git(['commit', '-m', 'Edit %s chunk' % chunk])
+
+        plugin = morphlib.plugins.branch_and_merge_plugin.BranchAndMergePlugin
+        chunk_dir = os.path.join(
+                self.branch_dir, plugin.convert_uri_to_path(chunk_repo_uri))
+        run_git(['reset', '--hard', tag], cwd=chunk_dir)
+
+        self._copy_chunk_morph_if_missing(chunk_dir, chunk, original_ref)
+
 
 class TestInitialDeployment(object):
     '''
@@ -476,22 +532,20 @@ class BaseTestSuite(object):
         return SystemTestBranch(workspace_dir, name)
 
 
-class TestUpgrades(BaseTestSuite):
-    def set_lighttpd_version(self, branch, tag='baserock/morph'):
-        '''
-        Use 'morph edit' and 'git reset' to force a specific lighttpd version.
-        '''
-        run_morph(['edit', 'trove-system-x86_64', 'trove', 'lighttpd'],
-                cwd=branch.morphs_dir)
-        run_git(['add', 'trove.morph'], cwd=branch.morphs_dir)
-        run_git(['commit', '-m', 'Edit lighttpd chunk'], cwd=branch.morphs_dir)
-
-        chunk_dir = os.path.join(branch.branch_dir, 'upstream:lighttpd')
-        # Set the system branch's corresponding Git branch in the chunk repo
-        # to the specific ref. This chunk doesn't have a chunk morphology so
-        # there's no further work to do!
-        run_git(['reset', '--hard', tag], cwd=chunk_dir)
+@contextlib.contextmanager
+def set_directory(path):
+    '''
+    Context manager to set current working directory of a script.
+    '''
+    old_path = os.getcwd()
+    os.chdir(path)
+    try:
+        yield
+    finally:
+        os.chdir(old_path)
 
+
+class TestUpgrades(BaseTestSuite):
     @contextlib.contextmanager
     def given_out_of_date_trove_instance(self, vm_name, fixture_dir, reuse=False):
         '''
@@ -503,7 +557,9 @@ class TestUpgrades(BaseTestSuite):
             instance.admin_id = os.path.join(branch.morphs_dir, 'testuser.key')
         else:
             branch = self.create_system_branch(fixture_dir, 'old')
-            self.set_lighttpd_version(branch, tag='lighttpd-1.3.14')
+            branch.set_chunk_version(
+                    system='trove-system-x86_64', stratum='trove',
+                    chunk='lighttpd', tag='lighttpd-1.3.14')
 
             instance = TroveInitialDeployment(branch, vm_name)
             instance.create_config()