This article records the steps of deploying the flask project and some problems encountered.
1. Python installation
If the python version of the server itself is high enough, you can skip this step.
View Python version number
When Python is installed on Linux (default installation), you only need to enter a simple command to view the Python version number:
# python -V Python 2.7.5
It can be seen that the Python version that comes with the system is 2.7.5.
Download the new version
To find the download address of the latest version, go directly to the official Python website to find the download address of the latest version. Copy the link address in the picture below.
Download compressed package
wget https://www.python.org/ftp/python/3.9.6/Python-3.9.6.tgz
If wget is not installed, run yum -y install wget directly. -y means agreeing all the way.
Unzip
After the download is complete, unzip it:
# tar -zxvf Python-3.9.6.tgz
- 1
Installation configuration
Enter the decompressed directory and install the configuration:
# cd Python-3.9.6/ # ./configure
When executing ./configure, if an error is reported:
configure: error: no acceptable C compiler found in $PATH
Explanation: The appropriate compiler is not installed. At this time, you need to install/upgrade gcc and other dependent packages.
# yum install make gcc gcc-c++
- 1
After completion, re-execute:
# ./configure
Compile & amp; Install
After the configuration is complete, you can compile:
# make
- 1
Long wait… Once completed, install:
# make install
Verification
After the installation is successful, you can check the Python version:
# python -V Python 2.7.5 # python3 -V Python 3.9.6
At this point, the installation of python is complete. There is still an operation to change python3 to the default version. I have not done it. If you want to do it, you need to search it yourself.
Create a virtual environment
Upload our project to the server
Go to the folder you uploaded to
cd folder path
Create a python virtual environment under this path
python3 -m venv mvenv
After creation, enter the environment
source mvenv\bin\activate
Then pip adds the packages required by the project. You can export the dependent package files locally in advance and then import them in the virtual environment.
pip freeze >./requirements-all.txt #Create a dependency package file information in the root directory pip install -r requirements-all.txt #Import dependency package file information
If the download is very slow and results in an error, you can change it to a domestic source and add
-i https://pypi.tuna.tsinghua.edu.cn/simple/ --trusted-host mirrors.aliyun.com
Now the entire virtual environment is configured, but if we start the service now, it still cannot be accessed by the public network. We need to install gunicorn first.
pip install gunicorn
After installing gunicorn we can start the service
gunicorn -w 2 -b 0.0.0.0:5656 pushup:app # -w is to start several processes # -b is the server port number to be bound
Now it is actually accessible. Let’s install nginx for proxy jump. I installed nginx because other computers could not access the write interface during testing.
Close guicorn
1. Find the process tree
pstree -ap|grep gunicorn
Obviously, 18745 is the main process of Gunicorn.
Exit task
kill -9 process ID
Nginx
My system is CentOS7. If it is different, you can search how to install your own. There are many online
Add Nginx to YUM source
sudo rpm -Uvh http://nginx.org/packages/centos/7/noarch/RPMS/nginx-release-centos-7-0.el7.ngx.noarch.rpm
Install Nginx
sudo yum install -y nginx
Start Nginx
sudo systemctl start nginx.service
If everything is normal, you should be able to access the default Welcome page when you open the browser. If it cannot be opened, it is probably because the network firewall has not opened port 80. The following is the solution (if you don’t encounter the problem of not being able to access the default page, you can check the settings and auto-start section below)
Check whether Nginx has run successfully
[root@localhost home]# ps aux|grep nginx root 36612 0.0 0.0 46464 972 ? Ss 19:49 0:00 nginx: master process /usr/sbin/nginx -c /etc/nginx/nginx.conf nginx 36613 0.0 0.1 46856 1604 ? S 19:49 0:00 nginx: worker process root 39654 0.0 0.0 112824 980 pts/0 S + 19:53 0:00 grep --color=auto nginx
Check whether port 80 is assigned to Nginx
[root@localhost \]# netstat -ntlp Active Internet connections (only servers) Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN 36612/nginx: master tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 1091/sshd tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 1272/master tcp6 0 0 :::22 :::* LISTEN 1091/sshd tcp6 0 0 ::1:25 :::* LISTEN 1272/master
Solution
The first step is to configure the firewall on port 80:
[root@localhost home]# firewall-cmd --zone=public --add-port=80/tcp --permanent
The second step is to restart the firewall service:
systemctl restart firewalld.service
Set Nginx to start automatically at boot
sudo systemctl enable nginx.service
If port 80 is still not accessible after doing this, it is recommended to change the listening port of nginx.
1. Modify the port listening address of nginx
1. Run the command find / -name nginx.conf to find the nginx.conf file. The path is generally /etc/nginx/nginx.conf.
2. Modify the nginx.conf file:
1) Run the command vim /etc/nginx/nginx.conf.
2) Press i key to enter editing mode.
3) Modify the following information in http:
Change to
Add redirect address
Add the following configuration to the server
location / {
proxy_pass http://127.0.0.1:8080; # This is the service address pointing to gunicorn host
proxy_set_header Host $host;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}
4) Press the Esc key to exit editing mode, and enter :wq to save and exit.
3. Restart the service.
systemctl reload nginx
Some other methods:
- Start service
systemctl start nginx
- Out of service:
systemctl restart nginx
- Reload nginx
systemctl reload nginx