roomservice: Migrate from GitHub API to git ls-remote

Change-Id: Ia62594dc0d350c2eaa93e9f02372443ac737abb7

build/tools/roomservice.py

@@ -22,6 +22,7 @@
 import netrc
 import os
 import re
+import subprocess
 import sys
 import urllib.error
 import urllib.parse
@@ -61,10 +62,6 @@
 except:
     githubauth = None
 
-def add_auth(githubreq):
-    if githubauth:
-        githubreq.add_header("Authorization","Basic %s" % githubauth)
-
 if not depsonly:
     githubreq = urllib.request.Request("https://raw.githubusercontent.com/LineageOS/mirror/main/default.xml")
     try:
@@ -269,24 +266,31 @@ def get_default_or_fallback_revision(repo_name):
     print("Default revision: %s" % default_revision)
     print("Checking branch info")
 
-    githubreq = urllib.request.Request("https://api.github.com/repos/LineageOS/" + repo_name + "/branches")
-    add_auth(githubreq)
-    result = json.loads(urllib.request.urlopen(githubreq, timeout=5).read().decode())
-    if has_branch(result, default_revision):
+    try:
+        stdout = subprocess.run(
+            ["git", "ls-remote", "-b", "https://:@github.com/LineageOS/" + repo_name],
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+        ).stdout.decode()
+        branches = [x.split("refs/heads/")[-1] for x in stdout.splitlines()]
+    except:
+        return ""
+
+    if default_revision in branches:
         return default_revision
 
     fallbacks = [ get_default_revision_no_minor() ]
     if os.getenv('ROOMSERVICE_BRANCHES'):
         fallbacks += list(filter(bool, os.getenv('ROOMSERVICE_BRANCHES').split(' ')))
 
     for fallback in fallbacks:
-        if has_branch(result, fallback):
+        if fallback in branches:
             print("Using fallback branch: %s" % fallback)
             return fallback
 
     print("Default revision %s not found in %s. Bailing." % (default_revision, repo_name))
     print("Branches found:")
-    for branch in [branch['name'] for branch in result]:
+    for branch in branches:
         print(branch)
     print("Use the ROOMSERVICE_BRANCHES environment variable to specify a list of fallback branches.")
     return ""