Intro To The Bottle Web Framework With Python

Intro

Recently I had to tutor a student on an assignment dealing with the bottle web framework. I had never used the framework before, but it works similar to Flask. It is a nice framework, and I would recommend it for beginners.

I will explore it more in the future to see how it scales in product, but I'm sure the develops over there have tested this.

Hello Bottle - The GET Request

Let's start with a basic GET request. Bottle create decorators that we can add to our function which will map HTTP requests to the function. We then call Bottle's run function at the end to server our app.

First, we install:

pip install bottle

Now, let's create a file for our app.

touch main.py

Alright, let's begin by importing the bottle framework. Inside of main.py (full file at the end).

import bottle

Next, let's create a hello function and add the @bottle.route decorator.

@bottle.route('/hello')
def hello():
    return "Hello World!"

Notice that we pass a string with our path name /hello. This tells bottle to serve our code on this route. For example, a user can navigate (or send a GET request) to our api with the hello path, i.e. (http://localhost:8080/hello). Then, Bottle will call our hello function and return the string "Hello World!".

Finally, at the end, we need to tell Bottle to run. We do this with the run function.

bottle.run(host='localhost', port=8080, debug=True)

We passed a few parameters here. We specificed the host to be our localhost, the port to be 8080, and we set debug to be True for testing purposed.

Now, we can point our browser to http://localhost:8080/hello and we will see "Hello World!".

Here is the full code.

import bottle

@bottle.route('/hello')
def hello():
    return "Hello World!"

bottle.run(host='localhost', port=8080, debug=True)

The POST request

Alright, so we learned how to do a basic GET request. Let's end by building a simple POST request. The pattern is similar to the above. Here is the code.

@bottle.post('/accept-some-data')
def handle_post():
    username = bottle.request.forms.get('username')
    return "Thank you, " + username

Here we changed the route decorator to post. That allows users to send a POST request to our api. We also use the bottle.request data to graph from data. This can come from an html form or form data from a curl request.

Conclusion

That's it for now! Bottle looks like a nice micro-framework for building out an api. If you use it in your projects, let me know what you build in the comments below. Check out more on the official website: https://bottlepy.org.