docparse-upload-process/lib/performOCR.js

process upload api request for the docparse server

var inspect = require('eyespect').inspector();
var fs = require('fs');
var request = require('request');

var async = require('async');
var config;
module.exports = function performOCR(data, callback) {
  config = data.config;
  var self = this;
  var file_name = data.file_name;
  var upload = data.upload;
  async.series([
    function(cb) {
      markUploadOCRStatusAsRunning(upload, cb);
    },

    function(cb) {
      // perfomr the ocr with the remote pdfer service
      getPdferURL(function (err, reply) {
        if (err) { return cb(err); }
        data.url = reply;
        cb();
      });
    },

    function(cb) {
      sendToPDFer(data, function (err, upload) {
        if (err) { return cb(err); }
        data.upload = upload;
        cb();
      });
    },
  ], function(err) {
    if (err) { return callback(err); }
    callback(null, data.upload);
  });
}

function sendToPDFer(data, cb) {
  inspect('sending upload data to pdfer');
  var timeout = 120*1000
  var opts = {
    url: data.url,
    timeout: timeout,
    json: true
  }
  var r = request.post(opts, function(err, response, body) {
    inspect('response recieved from pdfer');
    if (err) {
      inspect(err, 'error during upload create api request. The request to the remote pdfer service failed at url: ' + opts.url);
      return cb('error performing ocr on your upload: ' + err);
    }
    if (response.statusCode !== 200) {
      inspect(body,'body');
      return cb('error performing ocr on your upload. Invalid status code returned from pdfer service, body:' + body);
    }
    data.upload.status = body.status;
    data.upload.save(function (err) {
      if (err) {
        return cb('error performing ocr on your upload: ' + err);
      }
      cb(null, data.upload);
    });
  });
  var form = r.form();
  form.append('type', 'ocr');
  var filePath = data.filePath;
  var readStream = fs.createReadStream(filePath);
  readStream.on('error', function(err) {
    inspect(err, 'error reading test pdf file');
  });
  form.append('upload', readStream);
}


function markUploadOCRStatusAsRunning(upload, cb) {
  upload.ocr_status.started = true;
  upload.ocr_status.message = 'ocr running';
  upload.status = 'ocr in progress';
  upload.save(cb);
}

function markUploadOCRStatusAsComplete(upload, cb) {
  upload.ocr_status.complete = true;
  upload.ocr_status.started = false;
  upload.ocr_status.running = false;
  upload.ocr_status.message = 'ocr complete, waiting to parse';
  upload.status = 'ocr complete, waiting to parse';

  upload.save(cb);
}



function getPdferURL(cb) {
  var username = config.get('pdfer:username');
  var password = config.get('pdfer:password');
  var host = config.get('pdfer:host');
  var port = config.get('pdfer:port');

  if (!username || !password ||  !host) {
    var error_data = {
      message: 'failed to connect to remote pdfer service'
    }
    inspect('failed to create new docparse upload via api, pdfer settings missing from config parameter');
    return cb('failed to perform ocr on upload, pdfer service not available');


  }
  var url = 'http://'+username+':'+password+'@'+host + ':' + port
    +'/api/send'
  return cb(null, url);
}