Transform shapefiles to GeoJSON using the node-shp module

node-shp-walk.js

#!/usr/bin/env node

var fs = require('fs')
  , path = require('path')
  , walk = require('walk')
  , shp = require('shp');

if (process.argv.indexOf('--help') !== -1 || process.argv.indexOf('-h') !== -1) {
  console.log('Usage: geojson.js [input directory] [output directory]');
  process.exit(0);
}

// https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions
var inDir = process.argv[2] || '.'
  , outDir = process.argv[3] || path.join(inDir, 'geojson')
  , pattern = new RegExp('^' + inDir.replace(/[\\^$*+?.()|{}[\]-]/g, '\\$&'))
  , walker = walk.walk(inDir, {
    followLinks: false,
    filters: ['node_modules']
});

walker.on('file', function (root, fileStats, next) {
  if (fileStats.name.indexOf('.shp', fileStats.name.length - 4) !== -1) {
    var inFile = path.join(root, fileStats.name.slice(0, -4))
      , outFile = path.join(outDir, root.
        replace(pattern, '').
        replace(/^\//, '').
        replace(/\//g, '_') + '.geojson')
      , outStream = fs.createWriteStream(outFile);

    shp.readFile(inFile, function (err, data) {
      if (err) {
        console.error('Error parsing ' + inFile + ':', err);
        process.exit(1);
      }
      else {
        outStream.write(JSON.stringify(data), function () {
          console.log(outFile);
        });
      }
    });
  }
  next();
});