server/helpers/database-utils.js

   1 'use strict'
   2
   3 const retry = require('async/retry')
   4
   5 const db = require('../initializers/database')
   6 const logger = require('./logger')
   7
   8 const utils = {
   9   commitTransaction,
  10   retryTransactionWrapper,
  11   rollbackTransaction,
  12   startSerializableTransaction,
  13   transactionRetryer
  14 }
  15
  16 function commitTransaction (t, callback) {
  17   return t.commit().asCallback(callback)
  18 }
  19
  20 function rollbackTransaction (err, t, callback) {
  21   // Try to rollback transaction
  22   if (t) {
  23     // Do not catch err, report the original one
  24     t.rollback().asCallback(function () {
  25       return callback(err)
  26     })
  27   } else {
  28     return callback(err)
  29   }
  30 }
  31
  32 // { arguments, errorMessage }
  33 function retryTransactionWrapper (functionToRetry, options, finalCallback) {
  34   const args = options.arguments ? options.arguments : []
  35
  36   utils.transactionRetryer(
  37     function (callback) {
  38       return functionToRetry.apply(this, args.concat([ callback ]))
  39     },
  40     function (err) {
  41       if (err) {
  42         logger.error(options.errorMessage, { error: err })
  43       }
  44
  45       // Do not return the error, continue the process
  46       return finalCallback(null)
  47     }
  48   )
  49 }
  50
  51 function transactionRetryer (func, callback) {
  52   retry({
  53     times: 5,
  54
  55     errorFilter: function (err) {
  56       const willRetry = (err.name === 'SequelizeDatabaseError')
  57       logger.debug('Maybe retrying the transaction function.', { willRetry })
  58       return willRetry
  59     }
  60   }, func, callback)
  61 }
  62
  63 function startSerializableTransaction (callback) {
  64   db.sequelize.transaction({ isolationLevel: 'SERIALIZABLE' }).asCallback(function (err, t) {
  65     // We force to return only two parameters
  66     return callback(err, t)
  67   })
  68 }
  69
  70 // ---------------------------------------------------------------------------
  71
  72 module.exports = utils