Gerbonara

Gerbonara is a library to read, modify and write PCB manufacturing files such as Gerber, Excellon and IPC-356 through a pythonic API. Gerbonara can open a folder of manufacturing files, and parse file names and metadata to figure out which file contains what. Gerbonara is tested using an extensive library of real-world example files from CAD tools including KiCAD, Altium, Eagle, Allegro, gEDA, Fritzing, Siemens/Mentor Graphics PADS, and Target3001!.

Gerbonara's API is built on two principles:

Meaningful, object-oriented API

Gerbonara abstracts away the details of the underlying file format such as tool indices, coordinate notation and graphical state, and presents meaningful "graphical objects" such as a primitives.Line, primitives.Arc, or Region through its API. These objects can be easily created, manipulated or deleted from code without breaking anything else. You can even copy graphical objects between files, and Gerbonara will automatically convert coordinate format, units etc. for you. GerberFile and ExcellonFile use the same types of graphic objects <object-api>, so objects can be directly copied between file types without conversion.

Unit-safety

Gerbonara embeds physical LengthUnit information in all objects. The high-level API such as LayerStack.merge or GerberFile.offset accepts arguments with an explicitly given unit and automatically converts them as needed. Objects can be copied between GerberFile instances and unit conversion will be handled transparently in the background.

Gerbonara was started as an extensive refactoring of the pcb-tools and pcb-tools-extension packages. Both of these have statement-based APIs, that is, they parse input files into one python object for every line in the file. This means that when saving files they can recreate the input file almost byte by byte, but manipulating a file by changing statements without breaking things is hard.

Gerbonara powers gerbolyze, a tool for converting SVG vector graphics files into Gerber, and embedding SVG into existing Gerber files exported from a normal PCB tool for artistic purposes.

pip install --user gerbonara

from gerbonara import LayerStack

stack = LayerStack.from_directory('output/gerber')
w, h = stack.outline.size('mm')
print(f'Board size is {w:.1f} mm x {h:.1f} mm')

$ python -m gerbonara --help
[...]
$ python -m gerbonara render --help