Add support for Litestar (#13)

* Add ApitallyPlugin for Litestar

* Add identify_consumer_callback argument and fix validation error capture

* Add tests

* Fix test coverage

* Update readme

* Clean up

* Fix typing

* Add litestar to text matrix in CI

* Move start_time definition down

* Add filter_openapi_paths argument

* Use contextlib.suppress

* Improve typing for ApitallyClient

* Fix getting correct path from Request object

.github/workflows/tests.yaml

@@ -66,6 +66,9 @@ jobs:
           - django-ninja django
           - django-ninja==0.22.* django
           - django-ninja==0.18.0 django
+          - litestar
+          - litestar==2.6.1
+          - litestar==2.0.1
 
     steps:
       - uses: actions/checkout@v4

README.md

@@ -30,6 +30,7 @@ frameworks:
 - [Flask](https://docs.apitally.io/frameworks/flask)
 - [Django Ninja](https://docs.apitally.io/frameworks/django-ninja)
 - [Django REST Framework](https://docs.apitally.io/frameworks/django-rest-framework)
+- [Litestar](https://docs.apitally.io/frameworks/litestar)
 
 Learn more about Apitally on our 🌎 [website](https://apitally.io) or check out
 the 📚 [documentation](https://docs.apitally.io).
@@ -50,7 +51,8 @@ example:
 pip install apitally[fastapi]
 ```
 
-The available extras are: `fastapi`, `starlette`, `flask` and `django`.
+The available extras are: `fastapi`, `starlette`, `flask`, `django` and
+`litestar`.
 
 ## Usage
 
@@ -112,6 +114,27 @@ APITALLY_MIDDLEWARE = {
 }
 ```
 
+### Litestar
+
+This is an example of how to add the Apitally plugin to a Litestar application.
+For further instructions, see our
+[setup guide for Litestar](https://docs.apitally.io/frameworks/litestar).
+
+```python
+from litestar import Litestar
+from apitally.litestar import ApitallyPlugin
+
+app = Litestar(
+    route_handlers=[...],
+    plugins=[
+        ApitallyPlugin(
+            client_id="your-client-id",
+            env="dev",  # or "prod" etc.
+        ),
+    ]
+)
+```
+
 ## Getting help
 
 If you need help please

apitally/client/base.py

@@ -4,6 +4,7 @@
 import re
 import threading
 import time
+from abc import ABC
 from collections import Counter
 from dataclasses import dataclass
 from math import floor
@@ -26,16 +27,16 @@
 TApitallyClient = TypeVar("TApitallyClient", bound="ApitallyClientBase")
 
 
-class ApitallyClientBase:
+class ApitallyClientBase(ABC):
     _instance: Optional[ApitallyClientBase] = None
     _lock = threading.Lock()
 
-    def __new__(cls, *args, **kwargs) -> ApitallyClientBase:
+    def __new__(cls: Type[TApitallyClient], *args, **kwargs) -> TApitallyClient:
         if cls._instance is None:
             with cls._lock:
                 if cls._instance is None:
                     cls._instance = super().__new__(cls)
-        return cls._instance
+        return cast(TApitallyClient, cls._instance)
 
     def __init__(self, client_id: str, env: str) -> None:
         if hasattr(self, "client_id"):

apitally/litestar.py

@@ -0,0 +1,186 @@
+import contextlib
+import json
+import sys
+import time
+from importlib.metadata import version
+from typing import Callable, Dict, List, Optional
+
+from litestar.app import DEFAULT_OPENAPI_CONFIG, Litestar
+from litestar.config.app import AppConfig
+from litestar.connection import Request
+from litestar.datastructures import Headers
+from litestar.enums import ScopeType
+from litestar.handlers import HTTPRouteHandler
+from litestar.plugins import InitPluginProtocol
+from litestar.types import ASGIApp, Message, Receive, Scope, Send
+
+from apitally.client.asyncio import ApitallyClient
+
+
+__all__ = ["ApitallyPlugin"]
+
+
+class ApitallyPlugin(InitPluginProtocol):
+    def __init__(
+        self,
+        client_id: str,
+        env: str = "dev",
+        app_version: Optional[str] = None,
+        filter_openapi_paths: bool = True,
+        identify_consumer_callback: Optional[Callable[[Request], Optional[str]]] = None,
+    ) -> None:
+        self.client = ApitallyClient(client_id=client_id, env=env)
+        self.app_version = app_version
+        self.filter_openapi_paths = filter_openapi_paths
+        self.identify_consumer_callback = identify_consumer_callback
+        self.openapi_path: Optional[str] = None
+
+    def on_app_init(self, app_config: AppConfig) -> AppConfig:
+        app_config.on_startup.append(self.on_startup)
+        app_config.middleware.append(self.middleware_factory)
+        return app_config
+
+    def on_startup(self, app: Litestar) -> None:
+        openapi_config = app.openapi_config or DEFAULT_OPENAPI_CONFIG
+        self.openapi_path = openapi_config.openapi_controller.path
+
+        app_info = {
+            "openapi": _get_openapi(app),
+            "paths": [route for route in _get_routes(app) if not self.filter_path(route["path"])],
+            "versions": _get_versions(self.app_version),
+            "client": "python:litestar",
+        }
+        self.client.set_app_info(app_info)
+        self.client.start_sync_loop()
+
+    def middleware_factory(self, app: ASGIApp) -> ASGIApp:
+        async def middleware(scope: Scope, receive: Receive, send: Send) -> None:
+            if scope["type"] == "http" and scope["method"] != "OPTIONS":
+                request = Request(scope)
+                response_status = 0
+                response_time = 0.0
+                response_headers = Headers()
+                response_body = b""
+                start_time = time.perf_counter()
+
+                async def send_wrapper(message: Message) -> None:
+                    nonlocal response_time, response_status, response_headers, response_body
+                    if message["type"] == "http.response.start":
+                        response_time = time.perf_counter() - start_time
+                        response_status = message["status"]
+                        response_headers = Headers(message["headers"])
+                    elif message["type"] == "http.response.body" and response_status == 400:
+                        response_body += message["body"]
+                    await send(message)
+
+                await app(scope, receive, send_wrapper)
+                self.add_request(
+                    request=request,
+                    response_status=response_status,
+                    response_time=response_time,
+                    response_headers=response_headers,
+                    response_body=response_body,
+                )
+            else:
+                await app(scope, receive, send)  # pragma: no cover
+
+        return middleware
+
+    def add_request(
+        self,
+        request: Request,
+        response_status: int,
+        response_time: float,
+        response_headers: Headers,
+        response_body: bytes,
+    ) -> None:
+        if response_status < 100 or not request.route_handler.paths:
+            return  # pragma: no cover
+        path = self.get_path(request)
+        if path is None or self.filter_path(path):
+            return
+        consumer = self.get_consumer(request)
+        self.client.request_counter.add_request(
+            consumer=consumer,
+            method=request.method,
+            path=path,
+            status_code=response_status,
+            response_time=response_time,
+            request_size=request.headers.get("Content-Length"),
+            response_size=response_headers.get("Content-Length"),
+        )
+        if response_status == 400 and response_body and len(response_body) < 4096:
+            with contextlib.suppress(json.JSONDecodeError):
+                parsed_body = json.loads(response_body)
+                if (
+                    isinstance(parsed_body, dict)
+                    and "detail" in parsed_body
+                    and isinstance(parsed_body["detail"], str)
+                    and "validation" in parsed_body["detail"].lower()
+                    and "extra" in parsed_body
+                    and isinstance(parsed_body["extra"], list)
+                ):
+                    self.client.validation_error_counter.add_validation_errors(
+                        consumer=consumer,
+                        method=request.method,
+                        path=path,
+                        detail=[
+                            {
+                                "loc": [error.get("source", "body")] + error["key"].split("."),
+                                "msg": error["message"],
+                                "type": "",
+                            }
+                            for error in parsed_body["extra"]
+                            if "key" in error and "message" in error
+                        ],
+                    )
+
+    def get_path(self, request: Request) -> Optional[str]:
+        path: List[str] = []
+        for layer in request.route_handler.ownership_layers:
+            if isinstance(layer, HTTPRouteHandler):
+                if len(layer.paths) == 0:
+                    return None  # pragma: no cover
+                path.append(list(layer.paths)[0].lstrip("/"))
+            else:
+                path.append(layer.path.lstrip("/"))
+        return "/" + "/".join(filter(None, path))
+
+    def filter_path(self, path: str) -> bool:
+        if self.filter_openapi_paths and self.openapi_path:
+            return path == self.openapi_path or path.startswith(self.openapi_path + "/")
+        return False  # pragma: no cover
+
+    def get_consumer(self, request: Request) -> Optional[str]:
+        if hasattr(request.state, "consumer_identifier"):
+            return str(request.state.consumer_identifier)
+        if self.identify_consumer_callback is not None:
+            consumer_identifier = self.identify_consumer_callback(request)
+            if consumer_identifier is not None:
+                return str(consumer_identifier)
+        return None
+
+
+def _get_openapi(app: Litestar) -> str:
+    schema = app.openapi_schema.to_schema()
+    return json.dumps(schema)
+
+
+def _get_routes(app: Litestar) -> List[Dict[str, str]]:
+    return [
+        {"method": method, "path": route.path}
+        for route in app.routes
+        for method in route.methods
+        if route.scope_type == ScopeType.HTTP and method != "OPTIONS"
+    ]
+
+
+def _get_versions(app_version: Optional[str]) -> Dict[str, str]:
+    versions = {
+        "python": f"{sys.version_info.major}.{sys.version_info.minor}.{sys.version_info.micro}",
+        "apitally": version("apitally"),
+        "litestar": version("litestar"),
+    }
+    if app_version:
+        versions["app"] = app_version
+    return versions