Dump the names of all symbols in a Sketch file to an alphabetically sorted text file.

symbol-names.py

import os
import zipfile
import tempfile
import sys
import json

sketch_doc = sys.argv[1]

def get_symbol_names(zipname):
    symbol_names = []

    # read the sketch file as a zip file          
    with zipfile.ZipFile(zipname, 'r') as sketch_file:
        for item in sketch_file.infolist():
            data = sketch_file.read(item.filename)

            # find pages and collect symbol names
            if item.filename.startswith('pages') and item.filename.endswith('.json'):
                parsed_json = json.loads(data)
                for layer in parsed_json['layers']:

                    # only collect names of symbol masters
                    if layer['_class'] == 'symbolMaster':
                        symbol_names.append(layer['name'])
        sketch_file.close()

    sorted_symbol_names = sorted(symbol_names)

    # make new file for symbol names
    out_name = '%s-symbol-names.txt' % sketch_doc
    out = open(out_name, 'w+')

    for item in sorted_symbol_names:
        line = '%s\r\n' % item
        out.write(line)
    
    out.close()
    print 'Found %d symbols in the document.' % len(symbol_names)

get_symbol_names(sketch_doc)