uwsgi + nginx 部署python Flask项目

参考：

https://www.runoob.com/django/django-nginx-uwsgi.html

https://www.jianshu.com/p/6452596c4edb

1.基本流程

# 安装flask
$ pip install flask

然后写一个简单的服务，我就写一个控制直播推流的开关

from flask import Flask

app = Flask(__name__)

global status

@app.route('/on')
def turn_on():
    global status
    status = 1
    return 'living server is on!'

@app.route('/off')
def turn_off():
    global status
    status = 0
    return 'living server is off!'

@app.route('/status')
def live_status():
   global status
   return str(status);

if __name__ == '__main__':
    global status
    status = 1 ;
    app.run()
		

写好之后可以在本地跑起来试试，端口默认5000

然后安装uwsgi

$ pip install uwsgi

在/usr/local/live/uwsgi_script/路径下建立目录写配置文件uwsgi.ini

(我们新建文件夹uwsgi_script用来放uwsgi信息)

配置的时候也要带上开头的[uwsgi]，一开始我没有注意，项目一直没有运行起来

[uwsgi]					
socket          = 127.0.0.1:7100
chdir           = /usr/local/live
wsgi-file       = servers.py
callable        = app 
processes       = 4
vacuum          = true
master          = true

再写nginx配置

server {
    
    listen 8050;
    
    server_name data.migelab.com;
    charset utf-8;
    
    client_max_body_size 75M;
    
    location / { 
 
        include uwsgi_params;                       # 导入uwsgi配置 
    
        uwsgi_pass 127.0.0.1:7100;                  # 转发端口，需要和uwsgi配置当中的监听端口一致
        uwsgi_param UWSGI_PYTHON /usr/bin/python3;  
        uwsgi_param UWSGI_CHDIR /usr/local/live;    # 项目根目录
        uwsgi_param UWSGI_SCRIPT servers:app;           
    }   
}

# 启动nginx	
./nginx
./objs/nginx -c ./conf/nginx.conf

#	启动uwsgi
uwsgi --ini /usr/local/live/uwsgi_script/uwsgi.ini &

2.功能升级

主要是升级两个内容：加入使用POST和GET方法；

​ 返回 JSON对象的响应；

​ 管理一个视频流升级为管理多个视频流

JSON格式响应：

参考链接：https://flask.palletsprojects.com/en/1.1.x/api/#flask.Flask.response_class

​ https://blog.csdn.net/weixin_41665106/article/details/105599235

使用JSON格式去响应前端的请求：

@app.route('/on', methods=['POST','GET'])
def turn_on():
    global status
    if request.method =='POST':
       camera = request.form['camera']
       print(camera)
       if camera != KeyError:
           status[int(camera)] = 1
           response = make_response({
               'status':'success',
               'code':'200',
               'ERROR':''
           },200)
           response.headers={
               'content-type':'JSON'
            }
           return response
       else :
           response =  make_response({
               'status': 'fail',
               'code': '400',
               'ERROR':'camera code error!'
            },400)
           response.headers = {
               'content-type': 'JSON'
           }
           return response
    else:
        response = make_response({
            'status': 'fail',
            'code': '500',
            'ERROR': 'GET method error!'
        }, 500)
        response.headers = {
            'content-type': 'JSON'
        }
        return response

# 解决问题：如何构建响应
#          如何带参数

处理异常：

#   异常类
global InvalidUsage
class InvalidUsage(Exception):
    status_code = 400

    def __init__(self,message,status_code=400):
        Exception.__init__(self)
        self.message = message
        self.status_code = status_code

@app.errorhandler(InvalidUsage)
def invalid_usage(error):
    response = make_response(error.message)
    response.status_code = error.status_code
    return response

使用了抛出异常之后，之前的响应代码就简化了许多：

@app.route('/on', methods=['POST','GET'])
def turn_on():
    global status
    if request.method =='POST':
       camera = request.form['camera']
       print(camera)
       if camera != KeyError:
           status[int(camera)] = 1
           response = make_response({
               'status':'success',
               'code':'200',
               'ERROR':''
           },200)
           response.headers={
               'content-type':'JSON'
            }
           return response
       else :
           raise InvalidUsage('camera code is inValid or empty', status_code=400)
    else:
        raise InvalidUsage('GET method is InValid',status_code = 403)
        

之后部署到服务器上提示无法识别global全局变量，又去查了一下flask全局变量的使用，然后改为使用session

又增添了一些新的功能：

from flask import Flask, url_for, request, render_template, make_response, session
from enum import Enum

app = Flask(__name__)
app.config['SECRET_KEY'] = '29348817403'

#   异常类
global InvalidUsage


class InvalidUsage(Exception):
    status_code = 400

    def __init__(self, message, status_code=400):
        Exception.__init__(self)
        self.message = message
        self.status_code = status_code


@app.errorhandler(InvalidUsage)
def invalid_usage(error):
    response = make_response(error.message)
    response.status_code = error.status_code
    return response


#   枚举所有的摄像头
class Camera(Enum):
    SMARTHOME_FRONT = 1  # 智能家居正面
    SMARTHOME_LEFT = 2  # 智能家居左侧
    SMARTHOME_RIGHT = 3  # 智能家居右侧
    SMARTHOME_BACK = 4  # 智能家居背侧


# 设置服务初始值
# 摄像头状态
# 摄像头url
@app.route('/', methods=['POST', 'GET'])
def init():
    for i in range(Camera.__len__()):
        session[str(i)] = 0
    session['camera1'] = "https://live.test.tinylink.cn/live?port=1935&app=myapp&stream=test"
    session['camera2'] = "https://live.test.tinylink.cn/live?port=1935&app=smarthome&stream=left"

    session['user'] = "root"
    session["experiment"] = "智能家居实验"

    print("init is ok")
    return "ok"


#   控制摄像头打开
#   参数：摄像头枚举代码
@app.route('/on', methods=['POST', 'GET'])
def turn_on():
    camera = request.form['camera']
    print(session)
    if camera != KeyError:
        session[camera] = 1
        return "200"
    else:
        raise InvalidUsage('camera code is inValid or empty', status_code=400)


#   关闭摄像头
#   参数：摄像头枚举代码

@app.route('/off', methods=['POST', 'GET'])
def turn_off():
    camera = request.form['camera']
    print(camera)
    if camera != KeyError:
        session[camera] = 0
        return "200"
    else:
        raise InvalidUsage('camera code is inValid or empty', status_code=400)


#   获取摄像头状态
#   参数：摄像头枚举代码
#   返回：0（关闭）1（运行）

@app.route('/status', methods=['POST', 'GET'])
def live_status():
    camera = request.values.get('camera')
    print(camera)
    print(session)
    if camera != KeyError:
        return str(session.get(camera))
    else:
        raise InvalidUsage('camera code is inValid or empty', status_code=400)


#   获取可用摄像头总个数
@app.route('/available', methods=['POST', 'GET'])
def camera_number():
    return str(Camera.__len__())


#   获取摄像头url
#   参数：摄像头枚举代码
#   返回：摄像头url
@app.route('/get/url', methods=['POST', 'GET'])
def camera_url():
    camera = request.values.get('camera')
    print(camera)
    print(session)
    if camera != KeyError:
        print(session[camera])
        print(session[camera] == '0')
        url = "camera" + camera
        if session.get(url) is None:
            raise InvalidUsage('camera url is empty', status_code=400)
        if session[camera] != 0:
            url = "camera" + camera
            return session.get(url)
        else:
            raise InvalidUsage('camera is off', status_code=400)
    else:
        raise InvalidUsage('camera code is inValid or empty', status_code=400)


#   获取用户名
#   返回用户名或抛出异常

@app.route('/get/user', methods=['POST', 'GET'])
def get_user():
    if session.get("user") is None:
        raise InvalidUsage('user is empty', status_code=400)
    else:
        return session['user']


#   设置用户名
#   参数：用户名字符串
@app.route('/set/user', methods=['POST', 'GET'])
def set_user():
    user = request.values.get('user')
    if user != KeyError:
        session['user'] = user
        return "200"
    else:
        raise InvalidUsage('user is inValid or empty', status_code=400)


#   获取实验名
#   返回实验名或抛出异常

@app.route('/get/experiment', methods=['POST', 'GET'])
def get_experiment():
    if session.get("experiment") is None:
        raise InvalidUsage('experiment is empty', status_code=400)
    else:
        return session['experiment']


#   设置实验名
#   参数：实验名字符串
@app.route('/set/experiment', methods=['POST', 'GET'])
def set_experiment():
    experiment = request.values.get('experiment')
    if experiment != KeyError:
        session['experiment'] = experiment
        return "200"
    else:
        raise InvalidUsage('experiment is inValid or empty', status_code=400)


if __name__ == '__main__':
    app.run(port=7100)