Allow a custom type to be used for Client promises (brianc#1518)

Matches the Pool API.

Author: charmander

lib/client.js

@@ -31,6 +31,7 @@ var Client = function (config) {
 
  var c = config || {}
 
+ this._Promise = c.Promise || global.Promise
  this._types = new TypeOverrides(c.types)
  this._ending = false
  this._connecting = false
@@ -232,7 +233,7 @@ Client.prototype.connect = function (callback) {
  return
  }
 
- return new Promise((resolve, reject) => {
+ return new this._Promise((resolve, reject) => {
  this._connect((error) => {
  if (error) {
  reject(error)
@@ -409,12 +410,9 @@ Client.prototype.query = function (config, values, callback) {
  } else {
  query = new Query(config, values, callback)
  if (!query.callback) {
- let resolveOut, rejectOut
- result = new Promise((resolve, reject) => {
- resolveOut = resolve
- rejectOut = reject
+ result = new this._Promise((resolve, reject) => {
+ query.callback = (err, res) => err ? reject(err) : resolve(res)
  })
- query.callback = (err, res) => err ? rejectOut(err) : resolveOut(res)
  }
  }
 
@@ -458,7 +456,7 @@ Client.prototype.end = function (cb) {
  if (cb) {
  this.connection.once('end', cb)
  } else {
- return new Promise((resolve) => {
+ return new this._Promise((resolve) => {
  this.connection.once('end', resolve)
  })
  }

lib/native/client.js

@@ -25,6 +25,7 @@ var Client = module.exports = function (config) {
  EventEmitter.call(this)
  config = config || {}
 
+ this._Promise = config.Promise || global.Promise
  this._types = new TypeOverrides(config.types)
 
  this.native = new Native({
@@ -121,7 +122,7 @@ Client.prototype.connect = function (callback) {
  return
  }
 
- return new Promise((resolve, reject) => {
+ return new this._Promise((resolve, reject) => {
  this._connect((error) => {
  if (error) {
  reject(error)
@@ -156,7 +157,7 @@ Client.prototype.query = function (config, values, callback) {
  query = new NativeQuery(config, values, callback)
  if (!query.callback) {
  let resolveOut, rejectOut
- result = new Promise((resolve, reject) => {
+ result = new this._Promise((resolve, reject) => {
  resolveOut = resolve
  rejectOut = reject
  })
@@ -196,11 +197,8 @@ Client.prototype.end = function (cb) {
  }
  var result
  if (!cb) {
- var resolve, reject
- cb = (err) => err ? reject(err) : resolve()
- result = new global.Promise(function (res, rej) {
- resolve = res
- reject = rej
+ result = new this._Promise(function (resolve, reject) {
+ cb = (err) => err ? reject(err) : resolve()
  })
  }
  this.native.end(function () {

package.json

@@ -29,6 +29,7 @@
  },
  "devDependencies": {
  "async": "0.9.0",
+ "bluebird": "3.5.2",
  "co": "4.6.0",
  "eslint": "4.2.0",
  "eslint-config-standard": "10.2.1",

test/integration/client/query-as-promise-tests.js

@@ -1,4 +1,5 @@
 'use strict'
+var bluebird = require('bluebird')
 var helper = require(__dirname + '/../test-helper')
 var pg = helper.pg
 
@@ -7,10 +8,10 @@ process.on('unhandledRejection', function (e) {
  process.exit(1)
 })
 
-const pool = new pg.Pool()
 const suite = new helper.Suite()
 
 suite.test('promise API', (cb) => {
+ const pool = new pg.Pool()
  pool.connect().then((client) => {
  client.query('SELECT $1::text as name', ['foo'])
  .then(function (result) {
@@ -31,3 +32,24 @@ suite.test('promise API', (cb) => {
  })
  })
 })
+
+suite.test('promise API with configurable promise type', (cb) => {
+ const client = new pg.Client({ Promise: bluebird })
+ const connectPromise = client.connect()
+ assert(connectPromise instanceof bluebird, 'Client connect() returns configured promise')
+
+ connectPromise
+ .then(() => {
+ const queryPromise = client.query('SELECT 1')
+ assert(queryPromise instanceof bluebird, 'Client query() returns configured promise')
+
+ return queryPromise.then(() => {
+ client.end(cb)
+ })
+ })
+ .catch((error) => {
+ process.nextTick(() => {
+ throw error
+ })
+ })
+});