README.md

Middleware

Middleware is what separates this BOM generator from others, even ones built into KiCad.

It has the power to completely alter a component list, contact external services, and muchmore.

Some examples of cool potential middleware:

• Using the DigiKey API to find prices or part numbers
• Looking up the part in database to find internal part numbers, etc...

How Middleware Works

Middleware works very similar to a "middleman" (hence, the name). It is called after all the components have been parsed, but before the output formatter is called.

Creating Middleware

Creating Middleware is nearly the exact process as creating a Formatter.

All Middleware Functions must accept, and return a KiCadComponentList

Step 1

The first step is to create a file in the Middleware folder (the same folder as this README)

The file MUST be in this format: "*_middleware.py" where * is the name of your middleware

Step 2

import the Middleware module

import Middleware

Step 3

Create a function for your middleware that registers it using the decorator.

This function must accept a list of components, and must return a list of components

@Middleware.Register("My-Middleware-Name")
def mymiddleware_middleware(components):
  """ A nice comment about what your Middleware does """
  # Code for your middleware

Note: the Middleware name is not case sensitive

Step 4

This is where Middleware and Formatters differ. If you want to add your newly created middleware to the pipeline, add the name of your middleware to the middleware array in config.json.