title: Async Tests
description: Write async tests with AsyncTestClient for JustAPI applications.
keywords: [JustAPI, async tests, pytest-asyncio, AsyncTestClient, TestClient]
JustAPI ships its own in-process test client — no external ASGI transport needed.
Use AsyncTestClient for async tests and JustAPITestClient for sync tests.
Async Test Client
import pytest
from justapi import JustAPIApp
from justapi.testing import AsyncTestClient
app = JustAPIApp()
@app.get("/hello")
async def hello():
return {"message": "Hello!"}
@pytest.mark.asyncio
async def test_hello():
async with AsyncTestClient(app) as client:
resp = await client.get("/hello")
assert resp.status == 200
assert resp.json() == {"message": "Hello!"}
The client runs the full Rust pipeline (routing, middleware, native fast path)
in-process, so tests exercise the same code paths as production.
Testing Database-Backed Routes
@pytest.mark.asyncio
async def test_db():
async with AsyncTestClient(app, database="sqlite::memory:") as client:
resp = await client.post("/items", b'{"name":"widget"}')
assert resp.status == 200
Fixtures
import pytest
from justapi.testing import AsyncTestClient
@pytest.fixture
async def client():
async with AsyncTestClient(app) as c:
yield c
@pytest.mark.asyncio
async def test_example(client):
resp = await client.get("/hello")
assert resp.status == 200
Supported Methods
get, post, put, patch, delete — each returns a response object with.status and .json() (mirroring the sync JustAPITestClient).