SSL for flask local development

Recently at HasGeek we moved all our web application to https. So I wanted to have all my development environment urls to have https.

How to have https in flask app

Method 1

from flask import Flask
app = Flask(__name__)
app.run('0.0.0.0', debug=True, port=8100, ssl_context='adhoc')

In the above piece of code, ssl_context variable is passed to werkezug.run_simple which creates SSL certificates using OpenSSL, you may need to install pyopenssl. I had issues with this method, so I generated self signed certificate.

Method 2

Generate a private key openssl genrsa -des3 -out server.key 1024

Generate a CSR
` openssl req -new -key server.key -out server.csr `

Remove Passphrase from key
`cp server.key server.key.org `
`openssl rsa -in server.key.org -out server.key `

Generate self signed certificate
`openssl x509 -req -days 365 -in server.csr -signkey server.key -out server.crt `

code

from flask import Flask
app = Flask(__name__)
app.run('0.0.0.0', debug=True, port=8100, ssl_context=('/Users/kracekumarramaraju/certificates/server.crt', '/Users/kracekumarramaraju/certificates/server.key'))

ssl_context can take option adhoc or tuple of the form (cert_file, pkey_file).

In case you are using /etc/hosts, add something similar 127.0.0.1 https://hacknight.local for accessing the web application locally.

Here is much detailed post about generating self signed certificates.

See also