Certificate Management Service:Install an SSL certificate on a Python Flask application program

Step 1: Download the certificate

1. Log on to the Certificate Management Service console.

2. In the left-side navigation pane, choose Certificate Management > SSL Certificate Management.

3. On the SSL Certificate Management page, find the certificate that you want to manage, click More in the Actions column. On the page that appears, click the Download tab.

4. Find Other in the Server Type column and click Download in the Actions column.

   

5. Decompress the downloaded certificate package.

   The following table describes the files that you can extract from the package. The files vary based on the certificate signing request (CSR) generation method that you use when you submit the certificate application.

   Value of the CSR Generation parameter	File extracted from the certificate package
   Automatic	Certificate file in the PEM format: Flask supports PEM files. A certificate file in the PEM format is a Base64-encoded text file that contains a complete certificate chain. The file is named in the Certificate ID_Domain name bound to the certificate format after decompression. Private key file in the KEY format: By default, the private key file is named in the Domain name bound to the certificate format.
   Manual	If you specify a CSR that is created in the Certificate Management Service console, the certificate file that is extracted from the downloaded certificate package is the same as the certificate file that is obtained in scenarios when you set the CSR Generation parameter to Automatic. If you specify a CSR that is not created in the Certificate Management Service console, only the PEM certificate file can be extracted from the downloaded certificate package. The password file or private key file cannot be extracted. You can use the certificate toolkit to convert your certificate file, password file, or private key file to the required format. For more information about how to convert certificate formats, see Convert the format of a certificate.

Step 2: Install the certificate for the Flask website

1. Run the following commands to create a directory to store the certificate in the /directory of the Linux server:

   mkdir /ssl # Create a directory named ssl.

2. Upload the certificate file and private key file to the following directory of the Linux server: /ssl.

   Note

   You can upload the file by using the file upload feature of a remote logon tool, such as PuTTY, Xshell, and WinSCP. For more information about how to upload a file to an Alibaba Cloud Elastic Compute Service (ECS) instance, see Use Remote Desktop Connection or Windows App to transfer files to a Windows instance or Upload a file to a Linux instance.

3. Open the Flask application file and configure the certificate based on the following sample code.

   The following sample code shows how to install a certificate on a Flask application. You can copy the code to a new file, specify the certificate path, and save the new file as test.py for testing.

   # Import the Flash web framework.
   from flask import Flask
   
   app = Flask(__name__)
   
   
   @app.route("/")
   def main():
       return "<p>Hello, World!</p>"
   
   
   # Configure the certificate.
   # Specify the default HTTPS port 443. 
   # Specify port 443 and the absolute path to the certificate. Replace /ssl/cert.pem with the absolute path to the certificate file. Replace /ssl/cert.key with the absolute path to the private key file. 
   context = (r'/ssl/cert.pem', r'/ssl/cert.key')
   app.run(host="0.0.0.0", port=443, ssl_context=context)
   

Step 3: Check whether the certificate is installed

https://yourdomain   # Replace yourdomain with the domain name that is bound to your certificate.

If a lock icon appears in the address bar, the certificate is installed.