192.168.2.124在哪里（192.168.2.53为什么打不开）

前言

在上一篇文章中，我们使用FastAPI编写了一个Flask风格的demo。在这篇文章里我们继续接着上篇的内容对FastAPI进行探究，这里面就包括了请求参数的处理，数据库的连接等。好了闲话少说，现在就开始这篇的内容。

获取路径参数

跟flask框架一样，fastapi也提供从url中获取参数的能力，具体怎么获取的我们用例子说明一些，代码如下所示:

├── app │ ├── api │ │ ├── __init__.py │ │ └── users.py │ ├── __init__.py ├── manage.py

2. 打开app/api/users.py文件，键入如下代码:

# app/api/users.py @users.get("/get_user/{id}") async def get_user_by_id(id: int): if id > 0: return {"username": "admin", "msg": "success", "code": 200} return {"msg": "failed", "code": 401}

3. 启动服务，并测试

分别打开两个bash,输入以下命令

curl -X GET "http://192.168.2.124:9000/api/get_user/0" {"msg":"failed","code":401}% curl -X GET "http://192.168.2.124:9000/api/get_user/10" {"username":"admin","msg":"success","code":200}%

服务日志信息如下

python manage.py INFO: Started server process [65515] INFO: Waiting for application startup. INFO: Application startup complete. INFO: Uvicorn running on http://0.0.0.0:9000 (Press CTRL C to quit) INFO: 192.168.2.207:54530 - "GET /api/get_user/0 HTTP/1.1" 200 OK INFO: 192.168.2.207:54532 - "GET /api/get_user/10 HTTP/1.1" 200 OK获取表单数据

当我们需要从表单中获取用户输入的数据使这个使用就需要使用到Form了

想要使用Form就需要提前安装python-multipart这个库

pip install python-multipart -i https://pypi.tuna.tsinghua.edu.cn/simple

2. 在视图函数中使用Form对象，具体代码如下所示:

# app/api/users.py from fastapi import APIRouter, Form users = APIRouter() @users.post("/login") async def login(username: str = Form(), password: str = Form()): if username and password: return {"msg": "success", "code": 200} return {"msg": "failed", "code": 401}

运行测试结果如下所示

curl -X POST -F "username=admin" -F "password=admin" "http://192.168.2.124:9000/api/login" {"msg":"success","code":200}% # 服务器运行日志输出如下 python manage.py INFO: Started server process [65590] INFO: Waiting for application startup. INFO: Application startup complete. INFO: Uvicorn running on http://0.0.0.0:9000 (Press CTRL C to quit) INFO: 192.168.2.207:54534 - "POST /api/login HTTP/1.1" 200 OK配置数据库和创建数据模型

很多web大都会提供一些orm的插件或者功能，例如Django就内置了orm，但是与之不一样的地方是像flask和fastapi这些小型框架却没有内置相对应的orm框架,而另辟蹊径采用插件集成的方式来支持数据的操作，这样做的好处是灵活，选择多。

安装tortoise-orm和aiomysql驱动

我们选择tortoise-orm这个第三方的orm框架，这个框架是参考django内置orm开发的

pip install tortoise-orm -i https://pypi.tuna.tsinghua.edu.cn/simple pip install aiomysql -i https://pypi.tuna.tsinghua.edu.cn/simple

2. 定义数据模型

# touch app/models/models.py创建模型文件 from tortoise import fields from tortoise.models import Model class User(Model): id = fields.IntField(pk=True) username = fields.CharField(max_length=30, unique=True, description="用户名") password = fields.CharField(max_length=128, description="密码")

3. 配置数据连接信息和初始化数据库

from fastapi import FastAPI from tortoise.contrib.fastapi import register_tortoise def create_app() -> FastAPI: app = FastAPI() register_rotuer(app) register_db(app) return app def register_rotuer(app: FastAPI) -> None: """注册路由""" from app.api import routers app.include_router(routers) def register_db(app: FastAPI) -> None: """"初始化数据库并根据数据模型生成对应的表""" register_tortoise( app, db_url="mysql://root:root12345678@192.168.2.124:3306/item_name", modules={"models": ["app.models.models"]},# 这是一个列表用来指明我们的模型文件的路径 generate_schemas=True, add_exception_handlers=True)

测试运行，登录mysql查看是否生成了数据表

python manage.py INFO: Started server process [66742] INFO: Waiting for application startup. /home/test/env/lib/python3.10/site-packages/aiomysql/cursors.py:239: Warning: Table 'user' already exists await self._query(query) INFO: Application startup complete. INFO: Uvicorn running on http://0.0.0.0:9000 (Press CTRL C to quit)

查看是否创建了数据表

mysql> desc user; ---------- -------------- ------ ----- --------- ---------------- | Field | Type | Null | Key | Default | Extra | ---------- -------------- ------ ----- --------- ---------------- | id | int | NO | PRI | NULL | auto_increment | | username | varchar(30) | NO | UNI | NULL | | | password | varchar(128) | NO | | NULL | | ---------- -------------- ------ ----- --------- ---------------- 3 rows in set (0.00 sec)在视图函数中操作模型数据

fastapi在视图函数中操作模型数据跟在flask中操作是类似的，具体如下所示

# app/api/users.py from fastapi import APIRouter, Form from app.models.models import User users = APIRouter() @users.post("/login") async def login(username: str = Form(), password: str = Form()): if username and password: return {"msg": "success", "code": 200} return {"msg": "failed", "code": 401} @users.get("/get_users") async def get_users(): return {"msg": "success", "code": 200} @users.get("/get_user/{id}") async def get_user_by_id(id: int): if id > 0: return {"username": "admin", "msg": "success", "code": 200} return {"msg": "failed", "code": 401} @users.post("/add") async def add(username: str = Form(), password: str = Form()): if username and password: u = await User.create(username=username, password=password) if u: return {"msg": "create user success", "code": 200} return {"msg": "create user failed", "code": 403} @users.get("/get_user/{id}") async def get_user(id: int): if id: data = await User.filter(id=id).first() return {"data": data, "msg": "success", "code": 200} return {"data": "", "msg": "success", "code": 200} @users.post("/update_user") async def update_user(id: str = Form(), name: str = Form()): if name and id: id = int(id) await User.filter(id=id).update(username=name) return {"msg": "success", "code": 200} return {"msg": "failed", "code": 400} @users.get("/delete_user/{id}") async def delete(id: int): if id: await User.filter(id=id).delete() return {"msg": "success", "code": 200} return {"msg": "failed", "code": 400}

运行测试结果如下所示:

curl -X POST -F "username=admin3" -F "password=admin3" "http://192.168.2.124:9000/api/add" {"msg":"create user success","code":200}% curl -X GET "http://192.168.2.124:9000/api/get_user/1" {"username":"admin","msg":"success","code":200}% curl -X POST -F "id=2" -F "name=admin2" "http://192.168.2.124:9000/api/update_user" {"msg":"success","code":200}% curl -X GET "http://192.168.2.124:9000/api/delete_user/2" {"msg":"success","code":200}% # 服务器运行输出日志如下 python manage.py INFO: Started server process [67038] INFO: Waiting for application startup. /home/test/env/lib/python3.10/site-packages/aiomysql/cursors.py:239: Warning: Table 'user' already exists await self._query(query) INFO: Application startup complete. INFO: Uvicorn running on http://0.0.0.0:9000 (Press CTRL C to quit) INFO: 192.168.2.207:54572 - "POST /api/add HTTP/1.1" 200 OK INFO: 192.168.2.207:54574 - "GET /api/get_user/1 HTTP/1.1" 200 OK INFO: 192.168.2.207:54576 - "POST /api/update_user HTTP/1.1" 200 OK INFO: 192.168.2.207:54578 - "GET /api/delete_user/2 HTTP/1.1" 200 OK

demo程序最终目录结构如下所示:

. ├── app │ ├── api │ │ ├── __init__.py │ │ └── users.py │ ├── __init__.py │ ├── models │ │ ├── __init__.py │ │ ├── models.py ├── manage.py小结

通过前后两篇文章我们大概知道了怎么去使用fastapi和其他插件来组织和编写web应用服务，虽然这其中的细节没有我没有细说，但是我觉得目前懂得怎么用就行了，细节方面我们在慢慢的进行补充就行了，fastapi的官方文档还是比较清晰易懂的(总之一句话有手就行，哈哈哈)。谢谢你能看到结尾，希望能帮到正在学习fastapi这个框架的你吧。