har2requests

• Step 1: Interact with a website from your usual browser
• Step 2: automatically generate the Python code to replay your requests

Motivation

To write bots in Python, the two main options are:

• requests to produce HTTP requests directly
• selenium to control a web browser

Of course, requests bots are more stable but they require more daunting work to reverse engineer the javascript code and reproduce every request made by the client.

Discover har2requests!

Features

• Automatic requests code generation from a HAR file
• Detection of the headers common to all requests and code factorization
• Clever inference on the origin of authorization headers
• Code formatting using black

Installation

pip install har2requests

Usage

From Chrome or Firefox, go to the Network tab of the Developer Tools, put the filters you want and export to HAR.

To read from a file:

har2requests input.har > output.py

To read from the clipboard:

pbpaste | har2requests - > output.py

By default, OPTIONS requests are ignored. To include them, use --include-options.

When encountering errors, you can use the --unsafe feature that will display warnings instead of errors if the HAR file does not fit the specification.

har2requests uses string matching algorithms to find the origin of authorization headers. If your file is too big, it might be slow. You can disable it with --no-infer.

Workflow tips

• --exclude-cookie-headers avoids the need to manually edit the output if all cookies are assigned by the website each session (the common scenario).
• --generate-assertions helps pinpoint unexpected variations quickly.
• --debug-requests helps if you need to debug the requests/responses themselves.