refactor(retry): migrate from backoff to tenacity

.pre-commit-config.yaml

@@ -96,9 +96,9 @@ repos:
     # `types-$lib` or `$lib-stubs`.
     additional_dependencies:
     - aiohttp==3.13.3
-    - backoff==2.2.1
     - cryptography==46.0.6
     - pyjwt==2.12.1
+    - tenacity==9.1.2
     - types-requests==2.32.4.20260324
     args:
     - --show-error-codes

auth/gcloud/aio/auth/token.py

@@ -17,9 +17,12 @@
 from urllib.parse import urlencode
 from urllib.parse import urlparse
 
-import backoff
 import cryptography  # pylint: disable=unused-import
 import jwt
+from tenacity import retry
+from tenacity import retry_if_exception_type
+from tenacity import stop_after_attempt
+from tenacity import wait_random_exponential
 
 from .build_constants import BUILD_GCLOUD_REST
 from .session import AioSession
@@ -276,7 +279,12 @@ async def ensure_token(self) -> None:
     async def refresh(self, *, timeout: int) -> TokenResponse:
         pass
 
-    @backoff.on_exception(backoff.expo, Exception, max_tries=5)
+    @retry(
+        retry=retry_if_exception_type(Exception),
+        stop=stop_after_attempt(5),
+        wait=wait_random_exponential(multiplier=1, max=60),
+        reraise=True,
+    )
     async def acquire_access_token(self, timeout: int = 10) -> None:
         resp = await self.refresh(timeout=timeout)
 

auth/pyproject.rest.toml

@@ -22,12 +22,12 @@ classifiers = [
 [tool.poetry.dependencies]
 python = ">= 3.10, < 4.0"
 # aiohttp = ">= 3.9.2, < 4.0.0"
-backoff = ">= 1.0.0, < 3.0.0"
-chardet = ">= 2.0, < 7.0"
+chardet = ">= 2.0, < 6.0"
 # See https://cryptography.io/en/latest/api-stability/#deprecation
 cryptography = ">= 2.0.0, < 49.0.0"  # pin max to < (major + 3)
 pyjwt = ">= 1.5.3, < 3.0.0"
 requests = ">= 2.2.1, < 3.0.0"
+tenacity = ">= 8.2.0, < 10.0.0"
 
 [tool.poetry.group.dev.dependencies]
 pytest = "9.0.2"

auth/pyproject.toml

@@ -22,12 +22,12 @@ classifiers = [
 [tool.poetry.dependencies]
 python = ">= 3.10, < 4.0"
 aiohttp = ">= 3.9.2, < 4.0.0"
-backoff = ">= 1.0.0, < 3.0.0"
-chardet = ">= 2.0, < 7.0"
+chardet = ">= 2.0, < 6.0"
 # See https://cryptography.io/en/latest/api-stability/#deprecation
 cryptography = ">= 2.0.0, < 49.0.0"  # pin max to < (major + 3)
 pyjwt = ">= 1.5.3, < 3.0.0"
 # requests = ">= 2.2.1, < 3.0.0"
+tenacity = ">= 8.2.0, < 10.0.0"
 
 [tool.poetry.group.dev.dependencies]
 pytest = "9.0.2"