crashless 0.0.12

Bugless future for our sanity sake

Crashless

Crash proof your code

Crashless enables you to catch those pesky bugs during backend development and correct them in real-time. Makes your development cycle smooth, so you can actually focus on building what actually matters.

Installation

Crashless is published as a Python package and can be installed with pip, ideally by using a virtual environment. Open up a terminal and install Crashless with:

pip install crashless

Add to FastAPI in 3 steps

1. Copy and paste the following server with a crashed endpoint to a file called main.py:

    from fastapi import FastAPI
   
    app = FastAPI()
   
   
    @app.get("/")
    def read_root():
        return {"message": "The server is running OK!"}
   
   
    @app.get("/crash")  # This endpoint has a fatal bug :(
    def crash():
        result = 8 + '7'
        return {'msg': f"Summing a+b = {result}"}
    
    
    # Adds Crashless
    import sys
    from crashless import fastapi_handler  # Imports library
    
    
    def in_dev_mode():
        """Knows if you are running in production or development mode"""
        return sys.argv[1] == 'dev'
    
    
    if in_dev_mode():  # If in dev mode adds an exception handler, that will suggest a possible fix.
        app.add_exception_handler(Exception, fastapi_handler.handle_exception)
   

   As you can see the /crash endpoint has an issue.

2. Run the server with:

    fastapi dev main.py
   

   If you don't have the fastapi command follow instructions here.

3. Go to http://127.0.0.1:8000 and check that it's running OK.

   Then go to http://127.0.0.1:8000/crash and see how it crashes.

   Now go to the terminal, where the server is running, and you'll see something like this:

    TypeError: unsupported operand type(s) for +: 'int' and 'str'
   
    Crashless detected an error, let's fix it!
    Loading possible solution...
    The following code changes will be applied:
   
     @app.get("/crash")  # This endpoint has a fatal bug :(
     def crash():
    -    result = 8 + '7'
    +    result = 8 + int('7')
     return {'msg': f"Summing a+b = {result}"}
   
   
    Explanation: The error occurred because you cannot add an integer and a string directly. The fix converts the string '7' to
    an integer using int('7') before performing the addition.
   

   You can apply changes by ENTERING a y. The changes will take place and the api reloads. If you try again you get 15!

Add to Django in 3 steps

coming soon!

Add to Flask in 3 steps

coming soon!

Links

Source Code: https://github.com/jisazaTappsi/crashless

Python library: https://pypi.org/project/crashless/