Flask+uwsgi+Nginx deploy application

I wrote a website with Flask before, and then I wanted to deploy it to a cloud host. After searching for a while, the deployment plan I decided to adopt is:

Web server using uWSGI
Use Supervisor to reference uwsgi as a regular startup service
Reverse proxy based on Nginx

Install Python environment, Flask

I applied for a cloud host on Vultr, and the system uses Ubuntu 15.10. Come up to install the python environment first, install pip, virtualenv. Create a new virtual environment venv and activate it:

wb@vultr:~/myBlog$ source venv/bin/activate
(venv) wb@vultr:~/myBlog$

Next, install Flask and Flask's dependencies, which depend on the project.
The startup file manage.py of my project is as follows:

import os

if os.path.exists('.env'):
    print('Importing environment from .env...')
    for line in open('.env'):
        var = line.strip().split('=')
        if len(var) == 2:
            os.environ[var[0]] = var[1]

from app import create_app, db
from app.models import User, Post
from flask.ext.script import Manager,Shell

app = create_app(os.getenv('FLASK_CONFIG') or 'default')
manager = Manager(app)

def make_shell_context():
    return dict(app=app,db=db,User=User)

manager.add_command("shell",Shell(make_context=make_shell_context))


if __name__=='__main__':
    manager.run()

So the way to run Flask is as follows:

python manage.py runserver --host 0.0.0.0

Then open the browser, enter your cloud host IP and port number (5000) such as: 1.2.3.4:5000, you can see your website.

Install uWSGI

The way to install uWSGI is also very simple, pip install it:

(venv) wb@vultr:~/myBlog$pip install uwsgi

After installation is complete configuration. config.iniCreate a new project in the project directory config.iniand enter the following in it:

[uwsgi]
master = true
home = venv
wsgi-file = manage.py
callable = app
socket = :3031
processes = 4
threads = 2
buffer-size = 32768

Among them, homeis the directory of the virtual environment, wsgi-fileis the python startup file, callable=appthis app is a variable in the manage.py program file, and the type of this variable is the application class of Flask. socketSpecifies the port to use at startup. I wrote it before http = 0.0.0.0:3031, but I found that it didn't work. After checking Stack Overflow, I changed it to socket.
Run uwsgi:

(venv) wb@vultr:~/myBlog$uwsgi config.ini
[uWSGI] getting INI configuration from config.ini
*** Starting uWSGI 2.0.12 (64bit) on [Thu Apr 21 08:41:52 2016] ***
compiled with version: 5.2.1 20151010 on 19 April 2016 02:03:42

At this point, uWSGI has been started normally and the Flask project has been loaded into it. ctrl+c closes the program. 1.2.3.4:3031At this point, you can see the project by typing in the browser . But this is only the command startup form, and it cannot be accessed when it is closed. To have it start with the server and run as a background service is what the runtime environment actually needs. Therefore, additional tools are needed to bootstrap uWSGI.

Install supervisor

我们使用supervisor引导uWSGI。安装方法：

sudo apt-get install supervisor

supervisor的全局配置文件在/etc/supervisor/supervisor.conf中，但是我们一般不改动，我们新建一个文件blog_supervisor.conf放在/etc/supervisor/conf.d目录下，里面输入以下内容：

[program:blog] 
# 启动命令入口 
command=/home/wb/myBlog/venv/bin/uwsgi /home/wb/myBlog/config.ini            
# 命令程序所在目录 
directory=/home/wb/myBlog
#运行命令的用户名 
user=wb
autostart=true
autorestart=true
#日志地址 
stdout_logfile=/home/wb/myBlog/logs/uwsgi_supervisor.log

启动supervisor服务：sudo service supervisor start

安装Nginx

Nginx是个著名的反向代理服务器。安装方法：

sudo apt-get install nginx

配置文件在/etc/nginx/sites-available中的default中，将其替换掉即可。新的default文件内容如下：

server { 
  listen 80; 
  server_name X.X.X.X; #公网地址 
  location / { 
  include uwsgi_params;
  uwsgi_pass 127.0.0.1:3031; # 指向uwsgi 所应用的内部地址,所有请求将转发给uwsgi 处理 
  uwsgi_param UWSGI_PYHOME /home/wb/myBlog/venv; # 指向虚拟环境目录 
  uwsgi_param UWSGI_CHDIR /home/wb/myBlog; # 指向网站根目录 
  uwsgi_param UWSGI_SCRIPT manage:app; # 指定启动程序
  uwsgi_read_timeout 100; 
 }  
}

重启Nginx服务：sudo service nginx restart
这时候打开浏览器，输入你的主机IP，就可以看到你的项目了。