mysociety/popit-api

#!/usr/bin/env node
"use strict";

/**
 * The migration tool in popit creates records with and ObjectId _id field,
 * but popit-api (this repo) is expecting them to be strings. This converts
 * existing documents to have a string _id field. It does this by looping
 * though all the records, copying existing documents into new documents
 * with string _ids and then removing the original document.
 */

var mongoose = require('mongoose');
var async = require('async');
var log = require('util').log;
require('../src/models');

var databaseName = process.argv[2];
var modelName = process.argv[3];

if (!databaseName || !modelName) {
  console.error("Usage:", process.argv[1], "<database-name> <modelName>");
  process.exit(1);
}

mongoose.connect('mongodb://localhost/' + databaseName);

var Model = mongoose.model(modelName);

Model.collection.find(function(err, docs) {
  if (err) {
    throw err;
  }
  docs.toArray(function(err, docs) {
    if (err) {
      throw err;
    }
    async.eachSeries(docs, changeDocId, onComplete);
  });
});

function changeDocId(doc, next) {
  log("Converting " + modelName + ' ' + doc._id);
  if ('string' === typeof doc._id) {
    return next();
  }
  var originalId = doc._id;
  doc._id = '' + doc._id;

  Model.collection.insert(doc, onInsert);

  function onInsert(err) {
    if (err) {
      return next(err);
    }
    Model.collection.remove({_id: originalId}, onRemove);
  }

  function onRemove(err) {
    if (err) {
      return next(err);
    }
    next();
  }
}

function onComplete(err) {
  if (err) {
    throw err;
  }
  log("Finished");
  process.exit();
}