manifest: Check all deps logs when picking cerbero commit

Instead of picking the 'slowest build', look at all the deps logs and
pick the commit that is mentioned in the maximum number of deps logs.

In practice, this will either be the newest commit or the previous
commit. If it's not the newest commit, we will warn and use an older
one.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-ci/-/merge_requests/349>

gitlab/build_manifest.py

@@ -12,6 +12,9 @@ import json
 from typing import Dict, Tuple, List
 # from pprint import pprint
 
+if sys.version_info < (3, 6):
+    raise SystemExit('Need Python 3.6 or newer')
+
 GSTREAMER_MODULES: List[str] = [
     'orc',
     'cerbero',
@@ -42,28 +45,64 @@ MANIFEST_TEMPLATE: str = """<?xml version="1.0" encoding="UTF-8"?>
 </manifest>"""
 
 
+CERBERO_DEPS_LOGS_TARGETS = (
+    ('cross-ios', 'universal'),
+    ('cross-windows-mingw', 'x86'),
+    ('cross-windows-mingw', 'x86_64'),
+    ('cross-android', 'universal'),
+    ('fedora', 'x86_64'),
+    ('macos', 'x86_64'),
+    ('windows-msvc', 'x86_64'),
+)
+
 # Disallow git prompting for a username/password
 os.environ['GIT_TERMINAL_PROMPT'] = '0'
 def git(*args, repository_path='.'):
     return subprocess.check_output(["git"] + list(args), cwd=repository_path).decode()
 
 def get_cerbero_last_build_info (branch : str):
-    # Take the log from slowest build to reduce cache misses, the logs are
-    # uploaded as soon as they are ready.
-    url = f'https://artifacts.gstreamer-foundation.net/cerbero-deps/{branch}/cross-ios/universal/cerbero-deps.log'
-    deps = [{'commit': None}]
+    # Fetch the deps log for all (distro, arch) targets
+    all_commits = {}
+    for distro, arch in CERBERO_DEPS_LOGS_TARGETS:
+        url = f'https://artifacts.gstreamer-foundation.net/cerbero-deps/{branch}/{distro}/{arch}/cerbero-deps.log'
+        print(f'Fetching {url}')
+        try:
+            req = urllib.request.Request(url)
+            resp = urllib.request.urlopen(req);
+            deps = json.loads(resp.read())
+        except urllib.error.URLError as e:
+            print(f'WARNING: Failed to GET {url}: {e!s}')
+            continue
 
-    try:
-        req = urllib.request.Request(url)
-        resp = urllib.request.urlopen(req);
-        deps = json.loads(resp.read())
-    except urllib.error.URLError as e:
-        print(f'Failed to get from URL {url}')
-        print('WARNING: Could not find a revision with build cache ready: ' + str(e))
-        print('Checking cerbero:', end=' ')
-        return None
+        for dep in deps:
+            commit = dep['commit']
+            if commit not in all_commits:
+                all_commits[commit] = []
+            all_commits[commit].append((distro, arch))
+
+    # Fetch the cerbero commit that has the most number of caches
+    best_commit = None
+    newest_commit = None
+    max_caches = 0
+    total_caches = len(CERBERO_DEPS_LOGS_TARGETS)
+    for commit, targets in all_commits.items():
+        if newest_commit is None:
+            newest_commit = commit
+        have_caches = len(targets)
+        # If this commit has caches for all targets, just use it
+        if have_caches == total_caches:
+            best_commit = commit
+            break
+        # Else, try to find the commit with the most caches
+        if have_caches > max_caches:
+            max_caches = have_caches
+            best_commit = commit
+    if newest_commit is None:
+        print('WARNING: No deps logs were found, will build from scratch')
+    if best_commit != newest_commit:
+        print(f'WARNING: Cache is not up-to-date for commit {newest_commit}, using commit {best_commit} instead')
+    return best_commit
 
-    return deps[0]['commit']
 
 def get_branch_info(module: str, namespace: str, branch: str) -> Tuple[str, str]:
     try: