【问题标题】：Deploying Flask application with Apache2 Proxy Server使用 Apache2 代理服务器部署 Flask 应用程序
【发布时间】：2022-11-12 09:08:50
【问题描述】：

我正在尝试在 Apache2 中使用带有代理服务器的 Gunicorn 部署 Flask 应用程序。 Flask 应用程序在 Docker 容器中运行，但不在 Apache2 服务器中。

这是Apache2的配置。

<Macro DemoSubdomain $subdomain_name $proxy_pass_proto $proxy_pass_to>
<VirtualHost *:443>
    ServerName $subdomain_name.example.com

    ProxyPass / $proxy_pass_proto://$proxy_pass_to
    RewriteEngine on
    RewriteCond %{HTTP:Upgrade} websocket [NC]
    RewriteCond %{HTTP:Connection} upgrade [NC]
    RewriteRule ^/?(.*) "ws://$proxy_pass_to/$1" [P,L]

    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined

    SSLEngine on
    SSLCertificateFile      /root/example.com-crt.pem
    SSLCertificateKeyFile   /root/example.com-key.pem
    SSLCertificateChainFile /root/example.com-chain.pem
</VirtualHost>
</Macro>

当 Config 中未指定“SERVER_NAME”时，Flask 应用程序在“subdomain_name.example.com”中运行，但是在调用重定向函数时，它会重定向到 localhost:17000。

因此，在 Flask 应用程序中，我将 config['SERVER_NAME'] 设置为 'subdomain_name.example.com' 并运行 Gunicorn。但是，我收到以下错误。

/usr/local/lib/python3.10/site-packages/flask/app.py:1777: UserWarning: Current server name 'localhost:17000' doesn't match configured server name 'subdomain_name.example.com'
app_1    |   return self.url_map.bind_to_environ(
app_1    | ERROR:some_app.app.app:Exception on / [GET]

我该如何解决这个问题？

【问题讨论】：

标签： python flask proxy apache2 gunicorn

【解决方案1】：

如果您的目标是使用 https 建立一个简单的网站，我可以提供我已采取的步骤。

很抱歉看到这篇文章的人，它很长。

从头开始设置一个新服务器（即，新鲜的Ubuntu Raspberry Pi 上的图像）

# Tell Universal Firewall (ufw) to Allow SSH connections (on the server)
sudo ufw allow 22
# Connect to the server using SSH
ssh ubuntu@servers.public.ip.addr
# Create some directories
mkdir repos
mkdir downloads
# Install Python3
sudo apt-get install python3-pip
# Install Virtualenv to avoid overlapping dependencies between different python scripts
sudo apt-get install python3-virtualenv
# Create a virtual environment
virtualenv .venv/
# Enter the virtual environment
. .venv/bin/activate
# type 'deactivate' to exit the virtual environment
####################################################
#####   TESTING FIREWALL/CONFIGURING PORTS   #######
####################################################
cd repos
# Run any app to debug your firewall's effect on Ports & Public IP Address
git clone https://github.com/org-not-included/simple_flask_app
cd simple_flask_app
# Install requirements
pip3 install -r requirements.txt
# Run script in background, and write terminal output to logs
python3 main.py &> server_run_details.log & disown
# type 'cat server_run_details.log' to see the logs
# Tell ufw to Allow connections on port 4020 
sudo ufw allow 4020
# Test the port connection locally
curl -X GET http://127.0.0.1:4020
# kill the Flask app
sudo fuser -k 4020/tcp
# Testing Port over Public IP:
# - skip to bottom of file (shift+g)
# - update '127.0.0.1' -> '0.0.0.0' (i)
# - save and quit (esc :wq! enter)
sudo vi main.py
sudo fuser -k 4020/tcp
python3 main.py &> server_run_details.log & disown
# In another browser try to hit the public IP in a terminal
curl -X GET http://servers.public.ip.addr:4020
# Or visit the website in a browser
http://servers.public.ip.addr:4020
# Congrats your Firewall works

恭喜，服务器接受 http 流量（通过`http://[Public IP]:[Port]`）

接下来，我们可以设置一个域名，这样用户就可以访问(http://)www.example.com而不是http://servers.public.ip.addr:4020。

步骤 2A：

告诉 DNS 提供商将流量重定向到您的 IP 地址

####################################################
####  CONFIGURING A DOMAIN NAME  (example.com)  ####
####################################################
# Tell your Domain Management Provider (porkbun.com, godaddy.com, etc) to point your domain name at your Public IP:
# - visit your Domain Management Provider
# - update the A Record's ANSWER to your Public IP
# - delete the CNAME Record
####################################################

步骤 2B：

设置 apache2 以重定向 http 流量

# Tell ufw to Allow connections over traffic over http (ie. port 80)
sudo ufw allow http
sudo apt update
# Install apache2 to redirect traffic from your domain name to Simple Flask App's Public IP + Port
sudo apt install apache2
# Remove everything from the default configuration and add your mapping for http traffic
### <VirtualHost *:80>
###         ServerName example.com
###         ServerAlias www.example.com
###         ProxyRequests Off
###         ProxyPreserveHost On
###         ProxyPass / http://localhost:4020/
###         ProxyPassReverse / http://localhost:4020/
### </VirtualHost>
sudo vi /etc/apache2/sites-available/000-default.conf 
# Install apache2 dependencies 
sudo a2enmod proxy
sudo a2enmod proxy_http
sudo a2enmod proxy_ajp
sudo a2enmod proxy_balancer
sudo a2enmod proxy_connect
sudo a2enmod proxy_html
sudo a2enmod ssl
# Tell apache2 to stop running 
sudo a2dissite 000-default.conf
# Tell apache2 to start running 
sudo a2ensite 000-default.conf
# Have the system manager restart apache2
sudo systemctl reload apache2
# Check the server logs
sudo systemctl status apache2.service

步骤 2C：

对域上的 http 流量进行故障排除

Visit your domain in web browser:
- example.com 
- www.example.com
- http://www.example.com

# Is Apache2 is running okay?
sudo systemctl status apache2.service
# If not
## Edit Apache2 Config
sudo vi /etc/apache2/sites-available/000-default.conf 
## Restart apache2
sudo a2dissite 000-default.conf
sudo a2ensite 000-default.conf
sudo systemctl reload apache2

# Is Apache2 is running okay?
sudo systemctl status apache2.service
# Restart Step 2C (insert recursion joke here)

# Is your app running okay?
curl -X GET http://my.public.ip.address:4020/

恭喜，您已确认您的服务器能够提供 http 流量！

下载一个SSH 捆绑包从你的域管理提供商.
将这些文件复制到您的服务器：

# Create a folder on server
ssh ubuntu@my.public.ip.address
mkdir -p /home/ubuntu/secrets/example/
exit
# Copy from local downloads to server
scp -r /local/directory/ ubuntu@my.public.ip.address:/home/ubuntu/secrets/example/

更新您的 apache2 配置以使用 https 流量而不是 http：

<VirtualHost *:443>
        ServerName example.com
        ServerAlias www.example.com
        SSLEngine on
        SSLCertificateFile /home/ubuntu/secrets/example/domain.cert.pem
        SSLCertificateKeyFile /home/ubuntu/secrets/example/private.key.pem
        SSLCertificateChainFile /home/ubuntu/secrets/example/intermediate.cert.pem
        ProxyRequests Off
        ProxyPreserveHost On
        ProxyPass / http://localhost: 4020
        ProxyPassReverse / http://localhost: 4020/
</VirtualHost>

sudo vi /etc/apache2/sites-available/000-default.conf
# Restart Apache2
sudo a2dissite 000-default.conf
sudo a2ensite 000-default.conf
sudo systemctl reload apache2
# Is Apache2 is running okay?
sudo systemctl status apache2.service

恭喜，您的网站现在应该提供 https 流量。

清理

杀死简单的烧瓶应用程序：

sudo fuser -k 4020/tcp

删除示例回购：

cd ..
rm -rf simple_flask_app

从 apache2 配置中删除示例

sudo vi /etc/apache2/sites-available/000-default.conf

否决我的帖子

** Good Luck Scrolling that far **

【讨论】：

恭喜，服务器接受 http 流量（通过http://[Public IP]:[Port]）