Adds basic retries to rest API requests for Python asyncio (#17014)

* Adds basic retries to API requests

 * This mimics the basic retries performed by urllib3 in the sync version

* update samples

* Only use retry client if number of retries is specified in the config

* Reorganize

* Remove class attribute

* close retry_client

---------

Co-authored-by: William Cheng <wing328hk@gmail.com>

modules/openapi-generator/src/main/resources/python/asyncio/rest.mustache

@@ -8,11 +8,14 @@ import re
 import ssl
 
 import aiohttp
+import aiohttp_retry
 
 from {{packageName}}.exceptions import ApiException, ApiValueError
 
 RESTResponseType = aiohttp.ClientResponse
 
+ALLOW_RETRY_METHODS = frozenset({'DELETE', 'GET', 'HEAD', 'OPTIONS', 'PUT', 'TRACE'})
+
 class RESTResponse(io.IOBase):
 
     def __init__(self, resp) -> None:
@@ -68,8 +71,24 @@ class RESTClientObject:
             trust_env=True
         )
 
+        retries = configuration.retries
+        if retries is not None:
+            self.retry_client = aiohttp_retry.RetryClient(
+                client_session=self.pool_manager,
+                retry_options=aiohttp_retry.ExponentialRetry(
+                    attempts=retries,
+                    factor=0.0,
+                    start_timeout=0.0,
+                    max_timeout=120.0
+                )
+            )
+        else:
+            self.retry_client = None
+
     async def close(self):
         await self.pool_manager.close()
+        if self.retry_client is not None:
+            await self.retry_client.close()
 
     async def request(
         self,
@@ -168,7 +187,12 @@ class RESTClientObject:
                          declared content type."""
                 raise ApiException(status=0, reason=msg)
 
-        r = await self.pool_manager.request(**args)
+        if self.retry_client is not None and method in ALLOW_RETRY_METHODS:
+            pool_manager = self.retry_client
+        else:
+            pool_manager = self.pool_manager
+
+        r = await pool_manager.request(**args)
 
         return RESTResponse(r)
 

modules/openapi-generator/src/main/resources/python/pyproject.mustache

@@ -16,6 +16,7 @@ urllib3 = ">= 1.25.3"
 python-dateutil = ">=2.8.2"
 {{#asyncio}}
 aiohttp = ">= 3.8.4"
+aiohttp-retry = ">= 2.8.3"
 {{/asyncio}}
 {{#tornado}}
 tornado = ">=4.2,<5"

modules/openapi-generator/src/main/resources/python/requirements.mustache

@@ -5,6 +5,7 @@ pydantic >= 2
 typing-extensions >= 4.7.1
 {{#asyncio}}
 aiohttp >= 3.0.0
+aiohttp-retry >= 2.8.3
 {{/asyncio}}
 {{#hasHttpSignatureMethods}}
 pycryptodome >= 3.9.0

modules/openapi-generator/src/main/resources/python/setup.mustache

@@ -21,6 +21,7 @@ REQUIRES = [
     "python-dateutil",
 {{#asyncio}}
     "aiohttp >= 3.0.0",
+    "aiohttp-retry >= 2.8.3",
 {{/asyncio}}
 {{#tornado}}
     "tornado>=4.2,<5",

samples/openapi3/client/petstore/python-aiohttp/petstore_api/rest.py

@@ -18,11 +18,14 @@ import re
 import ssl
 
 import aiohttp
+import aiohttp_retry
 
 from petstore_api.exceptions import ApiException, ApiValueError
 
 RESTResponseType = aiohttp.ClientResponse
 
+ALLOW_RETRY_METHODS = frozenset({'DELETE', 'GET', 'HEAD', 'OPTIONS', 'PUT', 'TRACE'})
+
 class RESTResponse(io.IOBase):
 
     def __init__(self, resp) -> None:
@@ -78,8 +81,24 @@ class RESTClientObject:
             trust_env=True
         )
 
+        retries = configuration.retries
+        if retries is not None:
+            self.retry_client = aiohttp_retry.RetryClient(
+                client_session=self.pool_manager,
+                retry_options=aiohttp_retry.ExponentialRetry(
+                    attempts=retries,
+                    factor=0.0,
+                    start_timeout=0.0,
+                    max_timeout=120.0
+                )
+            )
+        else:
+            self.retry_client = None
+
     async def close(self):
         await self.pool_manager.close()
+        if self.retry_client is not None:
+            await self.retry_client.close()
 
     async def request(
         self,
@@ -178,7 +197,12 @@ class RESTClientObject:
                          declared content type."""
                 raise ApiException(status=0, reason=msg)
 
-        r = await self.pool_manager.request(**args)
+        if self.retry_client is not None and method in ALLOW_RETRY_METHODS:
+            pool_manager = self.retry_client
+        else:
+            pool_manager = self.pool_manager
+
+        r = await pool_manager.request(**args)
 
         return RESTResponse(r)
 

samples/openapi3/client/petstore/python-aiohttp/pyproject.toml

@@ -15,6 +15,7 @@ python = "^3.7"
 urllib3 = ">= 1.25.3"
 python-dateutil = ">=2.8.2"
 aiohttp = ">= 3.8.4"
+aiohttp-retry = ">= 2.8.3"
 pem = ">= 19.3.0"
 pycryptodome = ">= 3.9.0"
 pydantic = ">=2"

samples/openapi3/client/petstore/python-aiohttp/requirements.txt

@@ -4,4 +4,5 @@ urllib3 >= 1.25.3, < 2.1.0
 pydantic >= 2
 typing-extensions >= 4.7.1
 aiohttp >= 3.0.0
+aiohttp-retry >= 2.8.3
 pycryptodome >= 3.9.0

samples/openapi3/client/petstore/python-aiohttp/setup.py

@@ -27,6 +27,7 @@ REQUIRES = [
     "urllib3 >= 1.25.3, < 2.1.0",
     "python-dateutil",
     "aiohttp >= 3.0.0",
+    "aiohttp-retry >= 2.8.3",
     "pem>=19.3.0",
     "pycryptodome>=3.9.0",
     "pydantic >= 2",