support multiple hosts in pg-connection-string

Author: Scrib3r

packages/pg-connection-string/index.d.ts

@@ -8,6 +8,7 @@ export interface ConnectionOptions {
   database: string | null | undefined
   client_encoding?: string
   ssl?: boolean | string
+  multihost?: string | null
 
   application_name?: string
   fallback_application_name?: string

packages/pg-connection-string/index.js

@@ -12,18 +12,26 @@ function parse(str) {
     return { host: config[0], database: config[1] }
   }
 
+  const multihost = str.includes(',')
+
   // Check for empty host in URL
 
   const config = {}
   let result
   let dummyHost = false
   if (/ |%[^a-f0-9]|%[a-f0-9][^a-f0-9]/i.test(str)) {
     // Ensure spaces are encoded as %20
-    str = encodeURI(str).replace(/\%25(\d\d)/g, '%$1')
+    str = encodeURI(str).replace(/%25(\d\d)/g, '%$1')
   }
 
+  let host = str
+  host = host.slice(host.indexOf('://') + 3).split(/[?/]/)[0]
+  host = decodeURIComponent(host.slice(host.indexOf('@') + 1))
+
+  const multihosts = host.split(',')
+
   try {
-    result = new URL(str, 'postgres://base')
+    result = new URL(str.replace(host, multihosts[0]), 'postgres://base')
   } catch (e) {
     // The URL is invalid so try again with a dummy host
     result = new URL(str.replace('@/', '@___DUMMY___/'), 'postgres://base')
@@ -34,11 +42,12 @@ function parse(str) {
   for (const entry of result.searchParams.entries()) {
     config[entry[0]] = entry[1]
   }
+  config.multihost = multihosts.length > 1 ? multihosts : null
 
   config.user = config.user || decodeURIComponent(result.username)
   config.password = config.password || decodeURIComponent(result.password)
 
-  if (result.protocol == 'socket:') {
+  if (result.protocol === 'socket:') {
     config.host = decodeURI(result.pathname)
     config.database = result.searchParams.get('db')
     config.client_encoding = result.searchParams.get('encoding')

packages/pg-connection-string/test/parse.js

@@ -1,7 +1,6 @@
 'use strict'
 
 var chai = require('chai')
-var expect = chai.expect
 chai.should()
 
 var parse = require('../').parse
@@ -16,6 +15,17 @@ describe('parse', function () {
     subject.database.should.equal('lala')
   })
 
+  it('using connection string with multiple hosts', () => {
+    const subject = parse('postgres://brian:pw@host1:123,host2:456/lala')
+    subject.user.should.equal('brian')
+    subject.host.should.equal('host1')
+    subject.multihost.should.deep.equal(['host1:123', 'host2:456'])
+
+    subject.port.should.equal('123')
+    subject.password.should.equal('pw')
+    subject.database.should.equal('lala')
+  })
+
   it('escape spaces if present', function () {
     var subject = parse('postgres://localhost/post gres')
     subject.database.should.equal('post gres')