If you are more comfortable writing code than using UI-based tools like the Extension Builder, you can also build your extension with a script using the ExtensionBundle object from mojo.extensions.

The example script below is part of the Boilerplate Extension, and is written to work with the other files in that repository. If your files are organized differently, you may need to make some changes to the script.

'''build RoboFont Extension'''

import os
from mojo.extensions import ExtensionBundle

# get current folder
basePath = os.path.dirname(__file__)

# source folder for all extension files
sourcePath = os.path.join(basePath, 'source')

# folder with python files
libPath = os.path.join(sourcePath, 'code')

# folder with html files
htmlPath = os.path.join(sourcePath, 'documentation')

# folder with resources (icons etc)
resourcesPath = os.path.join(sourcePath, 'resources')

# load license text from file
# see choosealicense.com for more open-source licenses
licensePath = os.path.join(basePath, 'license.txt')

# boolean indicating if only .pyc should be included
pycOnly = True

# name of the compiled extension file
extensionFile = 'myExtension.roboFontExt'

# path of the compiled extension
buildPath = os.path.join(basePath, 'build')
extensionPath = os.path.join(buildPath, extensionFile)

# initiate the extension builder
B = ExtensionBundle()

# name of the extension
B.name = "myExtension"

# name of the developer
B.developer = 'RoboDocs'

# URL of the developer
B.developerURL = 'http://github.com/roboDocs'

# extension icon (file path or NSImage)
imagePath = os.path.join(resourcesPath, 'icon.png')
B.icon = imagePath

# version of the extension
B.version = '0.2.3'

# should the extension be launched at start-up?
B.launchAtStartUp = True

# script to be executed when RF starts
B.mainScript = 'hello.py'

# does the extension contain html help files?
B.html = True

# minimum RoboFont version required for this extension
B.requiresVersionMajor = '3'
B.requiresVersionMinor = '3'

# scripts which should appear in Extensions menu
B.addToMenu = [
        'path' : 'doSomething.py',
        'preferredName': 'do something',
        'shortKey' : '',
        'path' : 'doSomethingElse.py',
        'preferredName': 'do something else',
        'shortKey' : '',

# license for the extension
with open(licensePath) as license:
    B.license = license.read()

# expiration date for trial extensions
B.expireDate = '2019-12-31'

# compile and save the extension bundle
print('building extension...', end=' ')
B.save(extensionPath, libPath=libPath, htmlPath=htmlPath, resourcesPath=resourcesPath, pycOnly=["3.6", "3.7"])

# check for problems in the compiled extension
Last edited on 01/09/2021