Day: October 19, 2023

flask的开发模式和生产模式（WSGI）

Flask容器化部署这篇文章介绍了一种利用WSGI技术，实现生产部署的方法。
WSGI介绍

我想了解flask run，下面是chatgpt的答复：

Flask is a micro web framework for Python that allows you to build web applications easily. When you use flask run to set up a web service, you are starting a development web server that comes bundled with Flask. This server is typically used for development and debugging purposes. It is not suitable for production use because it is single-threaded, not very robust, and not designed to handle a high volume of requests.

On the other hand, when you use a WSGI (Web Server Gateway Interface) server to deploy your Flask application, you are using a production-ready server to serve your application. WSGI is a standardized interface that allows web applications written in Python, like Flask, to be deployed on various web servers. When you deploy your Flask application with a WSGI server, such as Gunicorn, uWSGI, or mod_wsgi, you get a more robust and scalable web server setup that can handle concurrent requests and is better suited for production use.

Here are some key differences and considerations:

  1. Development vs. Production: flask run is intended for development and debugging, while WSGI servers are used in production environments.

  2. Scalability: WSGI servers can handle multiple concurrent requests and are suitable for scaling your application as traffic increases. Flask’s development server is not optimized for high concurrency.

  3. Reliability: WSGI servers are more reliable and have features like process management, worker processes, and failover mechanisms, making them better suited for handling production workloads.

  4. Deployment: When deploying your Flask application in a production environment, it’s recommended to use a WSGI server in conjunction with a reverse proxy server (like Nginx or Apache) for better performance, security, and load balancing.

In summary, while flask run is convenient for quickly testing your Flask application during development, it’s not suitable for production use. When deploying your Flask application for production, you should use a WSGI server for better performance, concurrency, and reliability.

在宿主机和容器里，分别查看ip地址

在mac上查看ip地址，比较方便的命令是

ifconfig en0 | grep inet

这条命令的解释如下

  1. Executes the "ifconfig" command to retrieve network configuration information for the "en0" network interface.
  2. Pipes (|) the output of the "ifconfig" command to the "grep inet" command.
  3. The "grep" command searches through the output and extracts any lines that contain the word "inet."

输出如下图

另外，也可以使用下面的命令查看ip地址，可以发现在宿主机和容器里，显示的ip地址是相同的。

# curl ifconfig.me
1.193.44.59#

宿主机

容器

解释如下

  • The command "curl ifconfig.me" is used to make an HTTP request to the ifconfig.me website, which is a service that provides your public IP address.

  • In the output you provided, "1.193.44.59" is the public IP address that was returned by the ifconfig.me service in response to your request. This is the public IP address that your device is using to communicate with the internet. It’s the address that other devices on the internet will see when they interact with your device.

  • Please note that public IP addresses can change, especially if you are using a dynamic IP assignment from your Internet Service Provider (ISP), so the IP address you see here may not be constant and could change over time.

在容器的bash环境里，输入hostname -i，显示当前容器对外暴露的ip地址

# hostname -i
XXX:XXXX:XXXa::d 192.168.194.13

这条命令解释如下

  • The command "hostname -i" is used to display the IP addresses associated with the current host or system. In the output you provided, you have two IP addresses listed:

    1. d07:b51a:cc66:a::d: This is an IPv6 address. IPv6 is the next-generation Internet Protocol designed to replace IPv4 due to the exhaustion of available IPv4 addresses.
    2. 192.168.194.13: This is an IPv4 address. IPv4 is the older and more widely used version of the Internet Protocol.

  • The output shows that your system has both an IPv6 and an IPv4 address associated with it. These addresses can be used for communication with other devices on a network, with IPv6 being used to support the transition to a more extensive address space as IPv4 addresses become scarcer.