test: decouple test components from httpx

examples/auto_retry/test_app.py

@@ -6,11 +6,10 @@
 import unittest
 from unittest import mock
 
-from fastapi.testclient import TestClient
-
 from dispatch import Client
 from dispatch.sdk.v1 import status_pb2 as status_pb
 from dispatch.test import DispatchServer, DispatchService, EndpointClient
+from dispatch.test.fastapi import http_client
 
 
 class TestAutoRetry(unittest.TestCase):
@@ -25,14 +24,14 @@ def test_app(self):
         from .app import app, dispatch
 
         # Setup a fake Dispatch server.
-        endpoint_client = EndpointClient(TestClient(app))
+        app_client = http_client(app)
+        endpoint_client = EndpointClient(app_client)
         dispatch_service = DispatchService(endpoint_client, collect_roundtrips=True)
         with DispatchServer(dispatch_service) as dispatch_server:
             # Use it when dispatching function calls.
             dispatch.set_client(Client(api_url=dispatch_server.url))
 
-            http_client = TestClient(app)
-            response = http_client.get("/")
+            response = app_client.get("/")
             self.assertEqual(response.status_code, 200)
 
             dispatch_service.dispatch_calls()

examples/getting_started/test_app.py

@@ -6,10 +6,9 @@
 import unittest
 from unittest import mock
 
-from fastapi.testclient import TestClient
-
 from dispatch import Client
 from dispatch.test import DispatchServer, DispatchService, EndpointClient
+from dispatch.test.fastapi import http_client
 
 
 class TestGettingStarted(unittest.TestCase):
@@ -24,14 +23,14 @@ def test_app(self):
         from .app import app, dispatch
 
         # Setup a fake Dispatch server.
-        endpoint_client = EndpointClient(TestClient(app))
+        app_client = http_client(app)
+        endpoint_client = EndpointClient(app_client)
         dispatch_service = DispatchService(endpoint_client, collect_roundtrips=True)
         with DispatchServer(dispatch_service) as dispatch_server:
             # Use it when dispatching function calls.
             dispatch.set_client(Client(api_url=dispatch_server.url))
 
-            http_client = TestClient(app)
-            response = http_client.get("/")
+            response = app_client.get("/")
             self.assertEqual(response.status_code, 200)
 
             dispatch_service.dispatch_calls()

examples/github_stats/test_app.py

@@ -6,10 +6,9 @@
 import unittest
 from unittest import mock
 
-from fastapi.testclient import TestClient
-
 from dispatch.function import Client
 from dispatch.test import DispatchServer, DispatchService, EndpointClient
+from dispatch.test.fastapi import http_client
 
 
 class TestGithubStats(unittest.TestCase):
@@ -24,14 +23,14 @@ def test_app(self):
         from .app import app, dispatch
 
         # Setup a fake Dispatch server.
-        endpoint_client = EndpointClient(TestClient(app))
+        app_client = http_client(app)
+        endpoint_client = EndpointClient(app_client)
         dispatch_service = DispatchService(endpoint_client, collect_roundtrips=True)
         with DispatchServer(dispatch_service) as dispatch_server:
             # Use it when dispatching function calls.
             dispatch.set_client(Client(api_url=dispatch_server.url))
 
-            http_client = TestClient(app)
-            response = http_client.get("/")
+            response = app_client.get("/")
             self.assertEqual(response.status_code, 200)
 
             while dispatch_service.queue:

pyproject.toml

@@ -15,15 +15,16 @@ dependencies = [
     "grpc-stubs >= 1.53.0.5",
     "http-message-signatures >= 0.4.4",
     "tblib >= 3.0.0",
-    "httpx >= 0.27.0",
     "typing_extensions >= 4.10"
 ]
 
 [project.optional-dependencies]
 fastapi = ["fastapi", "httpx"]
+flask = ["flask"]
 lambda = ["awslambdaric"]
 
 dev = [
+    "httpx >= 0.27.0",
     "black >= 24.1.0",
     "isort >= 5.13.2",
     "mypy >= 1.10.0",

src/dispatch/test/client.py

@@ -1,8 +1,7 @@
 from datetime import datetime
-from typing import Optional
+from typing import Mapping, Optional, Protocol, Union
 
 import grpc
-import httpx
 
 from dispatch.sdk.v1 import function_pb2 as function_pb
 from dispatch.sdk.v1 import function_pb2_grpc as function_grpc
@@ -12,6 +11,7 @@
     Request,
     sign_request,
 )
+from dispatch.test.http import HttpClient
 
 
 class EndpointClient:
@@ -24,15 +24,15 @@ class EndpointClient:
     """
 
     def __init__(
-        self, http_client: httpx.Client, signing_key: Optional[Ed25519PrivateKey] = None
+        self, http_client: HttpClient, signing_key: Optional[Ed25519PrivateKey] = None
     ):
         """Initialize the client.
 
         Args:
             http_client: Client to use to make HTTP requests.
             signing_key: Optional Ed25519 private key to use to sign requests.
         """
-        channel = _HttpxGrpcChannel(http_client, signing_key=signing_key)
+        channel = _HttpGrpcChannel(http_client, signing_key=signing_key)
         self._stub = function_grpc.FunctionServiceStub(channel)
 
     def run(self, request: function_pb.RunRequest) -> function_pb.RunResponse:
@@ -46,16 +46,10 @@ def run(self, request: function_pb.RunRequest) -> function_pb.RunResponse:
         """
         return self._stub.Run(request)
 
-    @classmethod
-    def from_url(cls, url: str, signing_key: Optional[Ed25519PrivateKey] = None):
-        """Returns an EndpointClient for a Dispatch endpoint URL."""
-        http_client = httpx.Client(base_url=url)
-        return EndpointClient(http_client, signing_key)
 
-
-class _HttpxGrpcChannel(grpc.Channel):
+class _HttpGrpcChannel(grpc.Channel):
     def __init__(
-        self, http_client: httpx.Client, signing_key: Optional[Ed25519PrivateKey] = None
+        self, http_client: HttpClient, signing_key: Optional[Ed25519PrivateKey] = None
     ):
         self.http_client = http_client
         self.signing_key = signing_key
@@ -120,9 +114,11 @@ def __call__(
         wait_for_ready=None,
         compression=None,
     ):
+        url = self.client.url_for(self.method)  # note: method==path in gRPC parlance
+
         request = Request(
             method="POST",
-            url=str(httpx.URL(self.client.base_url).join(self.method)),
+            url=url,
             body=self.request_serializer(request),
             headers=CaseInsensitiveDict({"Content-Type": "application/grpc+proto"}),
         )
@@ -131,10 +127,10 @@ def __call__(
             sign_request(request, self.signing_key, datetime.now())
 
         response = self.client.post(
-            request.url, content=request.body, headers=request.headers
+            request.url, body=request.body, headers=request.headers
         )
         response.raise_for_status()
-        return self.response_deserializer(response.content)
+        return self.response_deserializer(response.body)
 
     def with_call(
         self,

src/dispatch/test/fastapi.py

@@ -0,0 +1,10 @@
+from fastapi import FastAPI
+from fastapi.testclient import TestClient
+
+import dispatch.test.httpx
+from dispatch.test.client import HttpClient
+
+
+def http_client(app: FastAPI) -> HttpClient:
+    """Build a client for a FastAPI app."""
+    return dispatch.test.httpx.Client(TestClient(app))

src/dispatch/test/http.py

@@ -0,0 +1,30 @@
+from dataclasses import dataclass
+from typing import Mapping, Protocol
+
+
+@dataclass
+class HttpResponse(Protocol):
+    status_code: int
+    body: bytes
+
+    def raise_for_status(self):
+        """Raise an exception on non-2xx responses."""
+        ...
+
+
+class HttpClient(Protocol):
+    """Protocol for HTTP clients."""
+
+    def get(self, url: str, headers: Mapping[str, str] = {}) -> HttpResponse:
+        """Make a GET request."""
+        ...
+
+    def post(
+        self, url: str, body: bytes, headers: Mapping[str, str] = {}
+    ) -> HttpResponse:
+        """Make a POST request."""
+        ...
+
+    def url_for(self, path: str) -> str:
+        """Get the fully-qualified URL for a path."""
+        ...

src/dispatch/test/httpx.py

@@ -0,0 +1,39 @@
+from typing import Mapping
+
+import httpx
+
+from dispatch.test.http import HttpClient, HttpResponse
+
+
+class Client(HttpClient):
+    def __init__(self, client: httpx.Client):
+        self.client = client
+
+    def get(self, url: str, headers: Mapping[str, str] = {}) -> HttpResponse:
+        response = self.client.get(url, headers=headers)
+        return Response(response)
+
+    def post(
+        self, url: str, body: bytes, headers: Mapping[str, str] = {}
+    ) -> HttpResponse:
+        response = self.client.post(url, content=body, headers=headers)
+        return Response(response)
+
+    def url_for(self, path: str) -> str:
+        return str(httpx.URL(self.client.base_url).join(path))
+
+
+class Response(HttpResponse):
+    def __init__(self, response: httpx.Response):
+        self.response = response
+
+    @property
+    def status_code(self):
+        return self.response.status_code
+
+    @property
+    def body(self):
+        return self.response.content
+
+    def raise_for_status(self):
+        self.response.raise_for_status()

src/dispatch/test/service.py

@@ -8,7 +8,6 @@
 from typing import Dict, List, Optional, Set, Tuple
 
 import grpc
-import httpx
 from typing_extensions import TypeAlias
 
 import dispatch.sdk.v1.call_pb2 as call_pb
@@ -325,17 +324,6 @@ def _dispatch_continuously(self):
 
             try:
                 self.dispatch_calls()
-            except httpx.HTTPStatusError as e:
-                if e.response.status_code == 403:
-                    logger.error(
-                        "error dispatching function call to endpoint (403). Is the endpoint's DISPATCH_VERIFICATION_KEY correct?"
-                    )
-                else:
-                    logger.exception(e)
-            except httpx.ConnectError as e:
-                logger.error(
-                    "error connecting to the endpoint. Is it running and accessible from DISPATCH_ENDPOINT_URL?"
-                )
             except Exception as e:
                 logger.exception(e)
 

tests/test_client.py

@@ -2,14 +2,20 @@
 import unittest
 from unittest import mock
 
+import httpx
+
+import dispatch.test.httpx
 from dispatch import Call, Client
 from dispatch.proto import _any_unpickle as any_unpickle
 from dispatch.test import DispatchServer, DispatchService, EndpointClient
 
 
 class TestClient(unittest.TestCase):
     def setUp(self):
-        endpoint_client = EndpointClient.from_url("http://function-service")
+        http_client = dispatch.test.httpx.Client(
+            httpx.Client(base_url="http://function-service")
+        )
+        endpoint_client = EndpointClient(http_client)
 
         api_key = "0000000000000000"
         self.dispatch_service = DispatchService(endpoint_client, api_key)

tests/test_fastapi.py

@@ -30,6 +30,7 @@
 )
 from dispatch.status import Status
 from dispatch.test import DispatchServer, DispatchService, EndpointClient
+from dispatch.test.fastapi import http_client
 
 
 def create_dispatch_instance(app: fastapi.FastAPI, endpoint: str):
@@ -44,8 +45,7 @@ def create_dispatch_instance(app: fastapi.FastAPI, endpoint: str):
 def create_endpoint_client(
     app: fastapi.FastAPI, signing_key: Optional[Ed25519PrivateKey] = None
 ):
-    http_client = TestClient(app)
-    return EndpointClient(http_client, signing_key)
+    return EndpointClient(http_client(app), signing_key)
 
 
 class TestFastAPI(unittest.TestCase):

tests/test_http.py

@@ -14,6 +14,7 @@
 import httpx
 from cryptography.hazmat.primitives.asymmetric.ed25519 import Ed25519PublicKey
 
+import dispatch.test.httpx
 from dispatch.experimental.durable.registry import clear_functions
 from dispatch.function import Arguments, Error, Function, Input, Output, Registry
 from dispatch.http import Dispatch
@@ -87,7 +88,8 @@ def my_function(input: Input) -> Output:
                 f"You told me: '{input.input}' ({len(input.input)} characters)"
             )
 
-        client = EndpointClient.from_url(self.endpoint)
+        http_client = dispatch.test.httpx.Client(httpx.Client(base_url=self.endpoint))
+        client = EndpointClient(http_client)
 
         pickled = pickle.dumps("Hello World!")
         input_any = google.protobuf.any_pb2.Any()