server/initializers/migrator.js

   1 'use strict'
   2
   3 const waterfall = require('async/waterfall')
   4 const eachSeries = require('async/eachSeries')
   5 const fs = require('fs')
   6 const path = require('path')
   7
   8 const constants = require('./constants')
   9 const db = require('./database')
  10 const logger = require('../helpers/logger')
  11
  12 const migrator = {
  13   migrate: migrate
  14 }
  15
  16 function migrate (finalCallback) {
  17   waterfall([
  18
  19     function checkApplicationTableExists (callback) {
  20       db.sequelize.getQueryInterface().showAllTables().asCallback(function (err, tables) {
  21         if (err) return callback(err)
  22
  23         // No tables, we don't need to migrate anything
  24         // The installer will do that
  25         if (tables.length === 0) return finalCallback(null)
  26
  27         return callback(null)
  28       })
  29     },
  30
  31     function loadMigrationVersion (callback) {
  32       db.Application.loadMigrationVersion(callback)
  33     },
  34
  35     function abortMigrationIfNotNeeded (actualVersion, callback) {
  36       // No need migrations
  37       if (actualVersion >= constants.LAST_MIGRATION_VERSION) return finalCallback(null)
  38
  39       return callback(null, actualVersion)
  40     },
  41
  42     function getMigrations (actualVersion, callback) {
  43       // If there are a new migration scripts
  44       logger.info('Begin migrations.')
  45
  46       getMigrationScripts(function (err, migrationScripts) {
  47         return callback(err, actualVersion, migrationScripts)
  48       })
  49     },
  50
  51     function doMigrations (actualVersion, migrationScripts, callback) {
  52       eachSeries(migrationScripts, function (entity, callbackEach) {
  53         executeMigration(actualVersion, entity, callbackEach)
  54       }, function (err) {
  55         if (err) return callback(err)
  56
  57         logger.info('Migrations finished. New migration version schema: %s', constants.LAST_MIGRATION_VERSION)
  58         return callback(null)
  59       })
  60     }
  61   ], finalCallback)
  62 }
  63
  64 // ---------------------------------------------------------------------------
  65
  66 module.exports = migrator
  67
  68 // ---------------------------------------------------------------------------
  69
  70 function getMigrationScripts (callback) {
  71   fs.readdir(path.join(__dirname, 'migrations'), function (err, files) {
  72     if (err) return callback(err)
  73
  74     const filesToMigrate = []
  75
  76     files.forEach(function (file) {
  77       // Filename is something like 'version-blabla.js'
  78       const version = file.split('-')[0]
  79       filesToMigrate.push({
  80         version,
  81         script: file
  82       })
  83     })
  84
  85     return callback(err, filesToMigrate)
  86   })
  87 }
  88
  89 function executeMigration (actualVersion, entity, callback) {
  90   const versionScript = parseInt(entity.version)
  91
  92   // Do not execute old migration scripts
  93   if (versionScript <= actualVersion) return callback(null)
  94
  95   // Load the migration module and run it
  96   const migrationScriptName = entity.script
  97   logger.info('Executing %s migration script.', migrationScriptName)
  98
  99   const migrationScript = require(path.join(__dirname, 'migrations', migrationScriptName))
 100
 101   db.sequelize.transaction().asCallback(function (err, t) {
 102     if (err) return callback(err)
 103
 104     const options = {
 105       transaction: t,
 106       queryInterface: db.sequelize.getQueryInterface(),
 107       sequelize: db.sequelize,
 108       Sequelize: db.Sequelize
 109     }
 110     migrationScript.up(options, function (err) {
 111       if (err) {
 112         t.rollback()
 113         return callback(err)
 114       }
 115
 116       // Update the new migration version
 117       db.Application.updateMigrationVersion(versionScript, t, function (err) {
 118         if (err) {
 119           t.rollback()
 120           return callback(err)
 121         }
 122
 123         t.commit().asCallback(callback)
 124       })
 125     })
 126   })
 127 }