Module test_client 

In-process testing: TestClient dispatches requests through an Application without opening a socket, and the helpers beside it cover the rest of a test:

• TestClient::websocket drives a WebSocket route’s upgrade handler over an in-memory duplex (TestWebSocket);
• TestResponse::sse reads a text/event-stream response, streamed or buffered, and parses its events (TestSse, SseFrame);
• assert_openapi_snapshot compares the generated OpenAPI document with a committed file (RWS_UPDATE_SNAPSHOTS=1 rewrites it);
• TestDb (model-* features) gives each test a database that leaves nothing behind, and factory builds #[derive(Factory)] models with default values.

Everything here is for tests: nothing on the request path uses it. It is compiled into every build (like TestClient always was) so that an application’s own tests, in another crate, reach it without a feature of their own.

Modules

dbmodel-mysql or model-postgres or model-sqlite

A database per test that leaves nothing behind.

factorymodel-mysql or model-postgres or model-sqlite

Factories for models: #[derive(Factory)] (next to #[derive(Model)]) gives a model T::factory(), a ModelFactory that builds instances with a default value for every field, overrides from with, and saves them with create.

snapshot

Snapshot assertions for generated JSON: assert_openapi_snapshot compares an app’s OpenAPI document with a file committed beside the tests, so a change to the API shows up in review as a change to that file.

sse

Server-Sent Events in tests: TestResponse::sse returns a TestSse, which reads the response’s text/event-stream body — streamed (Sse::stream, Response::stream_pipe) as it arrives, or buffered (Sse::into_response) at once — and hands out SseFrames.

websocketNon-WebAssembly

WebSocket routes in tests: TestClient::websocket sends the opening handshake through the application, and when the route answers with WebSocket::upgrade’s 101, TestWebSocketRequest::connect runs its handler on a thread of its own over an in-memory duplex — the same handler the server would run, given the same reader and writer types it expects, with no socket in between. The test side is a TestWebSocket: it masks what it sends, as a browser does (the handler’s recv refuses unmasked frames), answers pings, and joins fragmented messages.

Structs

SseFrame

One dispatched Server-Sent Event.

SseParser

An incremental text/event-stream parser: feed it bytes in any chunks, get back the events they completed.

TestClient

An in-process HTTP test client that dispatches requests directly through an Application without opening a TCP socket.

TestDb

A database for one test; see the module docs.

TestDbBuilder

A TestDb being set up: add migration directories, then .await it (or call build).

TestRequest

A pending test request. Chain builder methods then call TestRequest::send.

TestResponse

The result of a dispatched test request.

TestSse

Server-Sent Events read from a test response; see the module docs.

TestWebSocket

The test side of an upgraded connection; see the module docs.

TestWebSocketRequest

A WebSocket upgrade request being built; see TestClient::websocket.

Traits

OpenApiSource

Something an OpenAPI document can be read from.

Functions

assert_json_snapshot

assert_openapi_snapshot for any JSON document (a JSON Schema, an MCP tools/list result, a response body).

assert_openapi_snapshot

Compare an OpenAPI document with the snapshot at path (see the module docs for normalization and RWS_UPDATE_SNAPSHOTS). source is the document’s text (app.openapi_spec(&config)), a TestResponse of it, or a TestClient whose app serves /openapi.json.