parser.js

'use strict';

/**
 * // parser middleware
 * // parse `git blame --line-porcelain` output
 * app.use(function(req, res, done) {
 *   req
 *     .pipe(new Parser())
 *     .pipe(new Result(function(blamed) {
 *        req.blamed = blamed;
 *        done();
 *     }));
 * });
 */

var stream = require('stream');
var util   = require('util');
var debug  = require('debug')('punish:parser');

function Parser() {
  stream.Transform.call(this, {objectMode: true});

  var collected = {};

  this._parse = function parse(line) {
    var record, values;

    if (/^\t/.test(line)) {
      record = collected;
      collected = {};
      record.source = line.replace(/^\t/, '');
      debug('record', record);
      return record;
    
    } else {
      values = line.split(' ');
      if (/^[0-9a-z]{40}/.test(values[0])) {
        collected.commit = values.slice(1);
        debug('line: commit = %s', collected.commit);
      } else {
        collected[values[0]] = values.slice(1).join(' ');
        debug('line: %s = %s', values[0], collected[values[0]]);
      }
      return null;
    }
  };

  this._committers = {};
  this._source = [];
}

util.inherits(Parser, stream.Transform);

Parser.prototype._transform = function transform(data, encoding, done) {
  var record, lines = data.toString('utf-8');
  // debug('data', lines);
  lines = lines.split(/\n/);
  
  for (var i = 0, l = lines.length; i < l; i++) {
    record = this._parse(lines[i]);
    if (record !== null) this.push(record);
  }

  done();
};

module.exports = Parser;