FastAPI 的單元測試
- 對於服務端來說，通常會對功能進行單元測試，也稱白盒測試
- FastAPI 集成了第三方庫，讓我們可以快捷的編寫單元測試
- FastAPI 的單元測試是基於 Pytest + Request 的
Pytest 學習
https://www.cnblogs.com/poloyy/tag/Pytest/
TestClient 簡單的栗子
#!usr/bin/env python
# -*- coding:utf-8 _*-
"""
# author: 小菠蘿測試筆記
# blog: https://www.cnblogs.com/poloyy/
# time: 2021/9/29 10:55 下午
# file: 37_pytest.py
"""
import uvicorn
from fastapi import FastAPI
from fastapi.testclient import TestClient app = FastAPI() @app.get("/")
async def read_main():
return {"msg": "Hello World"} # 宣告一個 TestClient，把 FastAPI() 例項物件傳進去
client = TestClient(app) # 測試用
def test_read_main():
# 請求 127.0.0.1:8080/
response = client.get("/")
assert response.status_code == 200
assert response.json() == {"msg": "Hello World"} if __name__ == '__main__':
uvicorn.run(app="37_pytest:app", reload=True, host="127.0.0.1", port=8080)
在該資料夾下的命令列敲
pytest 37_pytest.py
執行結果
TestClient 的原始碼解析
繼承了 requests 庫的 Session
所以可以像使用 requests 庫一樣使用 TestClient，擁有 requests 所有方法、屬性
重寫了 Session.requests 方法
重寫了 requests 方法，不過只是加了一句 url = urljoin(self.base_url, url) url 拼接程式碼，還有給函式引數都加了型別指示，更加完善啦~
自定義 websocket 連線方法
後面學到 webSocket 再詳細講他
重寫了 __enter__、__exit__ 方法
- Session 的這兩個方法還是比較簡陋的，TestClient 做了一次重寫，主要是為了新增非同步的功能（非同步測試後面詳解，這篇舉栗子的都是普通函式 def）
- 前面講過有 __enter__、__exit__ 方法的物件都是上下文管理器，可以用 with .. as ..語句來呼叫上下文管理器哦
.get() 方法
上面程式碼 client.get()，直接呼叫的就是 Session 提供的 get() 方法啦！
複雜的測試場景
服務端
#!usr/bin/env python
# -*- coding:utf-8 _*-
"""
# author: 小菠蘿測試筆記
# blog: https://www.cnblogs.com/poloyy/
# time: 2021/9/29 10:55 下午
# file: s37_pytest.py
"""
import uvicorn
from fastapi import FastAPI
from fastapi.testclient import TestClient app = FastAPI() @app.get("/")
async def read_main():
return {"msg": "Hello World"} # 宣告一個 TestClient，把 FastAPI() 例項物件傳進去
client = TestClient(app) # 測試用
def test_read_main():
# 請求 127.0.0.1:8080/
response = client.get("/")
assert response.status_code == 200
assert response.json() == {"msg": "Hello World"} from typing import Optional from fastapi import FastAPI, Header, HTTPException
from pydantic import BaseModel # 模擬真實 token
fake_secret_token = "coneofsilence" # 模擬真實資料庫
fake_db = {
"foo": {"id": "foo", "title": "Foo", "description": "There goes my hero"},
"bar": {"id": "bar", "title": "Bar", "description": "The bartenders"},
} app = FastAPI() class Item(BaseModel):
id: str
title: str
description: Optional[str] = None # 介面一：查詢資料
@app.get("/items/{item_id}", response_model=Item)
async def read_main(item_id: str, x_token: str = Header(...)):
# 1、校驗 token 失敗
if x_token != fake_secret_token:
raise HTTPException(status_code=400, detail="x-token 錯誤") # 2、若資料庫沒有對應資料
if item_id not in fake_db:
raise HTTPException(status_code=404, detail="找不到 item_id")
# 3、找到資料則返回
return fake_db[item_id] # 介面二：建立資料
@app.post("/items/", response_model=Item)
async def create_item(item: Item, x_token: str = Header(...)):
# 1、校驗 token 失敗
if x_token != fake_secret_token:
raise HTTPException(status_code=400, detail="x-token 錯誤") # 2、若資料庫已經存在相同 id 的資料
if item.id in fake_db:
raise HTTPException(status_code=400, detail="找不到 item_id") # 3、新增資料到資料庫
fake_db[item.id] = item # 4、返回新增的資料
return item if __name__ == '__main__':
uvicorn.run(app="s37_test_pytest:app", reload=True, host="127.0.0.1", port=8080)
單元測試
#!usr/bin/env python
# -*- coding:utf-8 _*-
"""
# author: 小菠蘿測試筆記
# blog: https://www.cnblogs.com/poloyy/
# time: 2021/9/29 10:55 下午
# file: s37_pytest.py
"""
from fastapi.testclient import TestClient
from .s37_test_pytest import app client = TestClient(app) def test_read_item():
expect = {"id": "foo", "title": "Foo", "description": "There goes my hero"}
headers = {"x-token": "coneofsilence"}
resp = client.get("/items/foo", headers=headers)
assert resp.status_code == 200
assert resp.json() == expect def test_read_item_error_header():
expect = {"detail": "x-token 錯誤"}
headers = {"x-token": "test"}
resp = client.get("/items/foo", headers=headers)
assert resp.status_code == 400
assert resp.json() == expect def test_read_item_error_id():
expect = {"detail": "找不到 item_id"}
headers = {"x-token": "coneofsilence"}
resp = client.get("/items/foos", headers=headers)
assert resp.status_code == 404
assert resp.json() == expect def test_create_item():
body = {"id": "foos", "title": "Foo", "description": "There goes my hero"}
headers = {"x-token": "coneofsilence"}
resp = client.post("/items/", json=body, headers=headers)
assert resp.status_code == 200
assert resp.json() == body def test_create_item_error_header():
body = {"id": "foo", "title": "Foo", "description": "There goes my hero"}
expect = {"detail": "x-token 錯誤"}
headers = {"x-token": "test"}
resp = client.post("/items/", json=body, headers=headers)
assert resp.status_code == 400
assert resp.json() == expect def test_create_item_error_id():
expect = {"detail": "找不到 item_id"}
body = {"id": "foo", "title": "Foo", "description": "There goes my hero"}
headers = {"x-token": "coneofsilence"}
resp = client.post("/items/", json=body, headers=headers)
assert resp.status_code == 400
assert resp.json() == expect
命令列執行
pytest test.py -sq
執行結果
> pytest s37_pytest.py -sq
......
6 passed in 0.40s