gh retry policy and exp backoff for urlopen

Author: AchimGaedkeLynker

recipe/fixup_sha.py

@@ -1,21 +1,55 @@
 # Call like python3 __file__ python/ray/_version.py 2.49.2
 
-import json; 
+import json
 import os
 import sys
-from urllib.request import urlopen; 
+import time
+from urllib.request import HTTPError, urlopen
+
+
+def get_commit_sha(ver: str) -> str:
+    """
+    Return sha from version tag commit
+    
+    Use retry information in headers and exponential backoff to address rate limiting issues.
+    See: https://docs.github.com/en/rest/using-the-rest-api/best-practices-for-using-the-rest-api?apiVersion=2022-11-28#handle-rate-limit-errors-appropriately
+    """
+    exp_backoff = 60
+    retry_count = 0
+    while True:
+        try:
+            content = urlopen(
+                f"https://api.github.com/repos/ray-project/ray/git/ref/tags/ray-{ver}"
+            ).read()
+            return json.loads(content)["object"]["sha"]
+        except HTTPError as e:
+            if retry_count < 10 and e.code == 403 and e.msg == "rate limit exceeded":
+                retry_count += 1
+                timeout = exp_backoff
+                if "retry-after" in e.hdrs:
+                    timeout = int(e.hdrs["retry-after"])
+                elif e.hdrs.get("x-ratelimit-remaining", None) == "0":
+                    timeout = max(int(e.hdrs["x-ratelimit-reset"]) - time.gmtime(), 0)
+                else:
+                    exp_backoff *= 1.5
+                print(f"{e}:, retrying after {timeout} s", file=sys.stderr)
+                time.sleep(timeout)
+                continue
+            raise
+
 
 versionpy = sys.argv[1]
 ver = sys.argv[2]
 
 assert os.path.exists(versionpy)
 
-content = urlopen(f'https://api.github.com/repos/ray-project/ray/git/ref/tags/ray-{ver}').read()
-sha = json.loads(content)['object']['sha']
-with open(versionpy, 'r') as fid:
+with open(versionpy, "r") as fid:
     txt = fid.read()
+
+sha = get_commit_sha(ver)
+
 txt = txt.replace("{{RAY_COMMIT_SHA}}", sha)
 assert f'version = "{ver}"' in txt
 assert f'commit = "{sha}"' in txt
-with open(versionpy, 'w') as fid:
+with open(versionpy, "w") as fid:
     fid.write(txt)