Support --loopback 127.0.0.1

vweevers · vweevers · commit 90775510e99e · 2020-08-26T20:30:08.000+02:00
#292 (comment)
diff --git a/README.md b/README.md
@@ -270,8 +270,7 @@ Usage: `airtap [options] <files>`. Supports multiple `files`. They can be paths
   --live                   keep browsers open to allow repeated test runs
   -p, --preset <preset>    select a configuration preset
   -s, --server <script>    path to script that runs a support server
-  --loopback <hostname>    custom hostname for tunneling, default
-                           airtap.local
+  --loopback <hostname>    custom hostname that equals or resolves to 127.0.0.1
   --verbose                enable airtap debug output
   --silly                  enable all debug output
   -h, --help               display help for command
diff --git a/bin/airtap.js b/bin/airtap.js
@@ -30,7 +30,7 @@ program
   .option('--live', 'keep browsers open to allow repeated test runs')
   .option('-p, --preset <preset>', 'select a configuration preset')
   .option('-s, --server <script>', 'path to script that runs a support server')
-  .option('--loopback <hostname>', 'custom hostname for tunneling, default airtap.local')
+  .option('--loopback <hostname>', 'custom hostname that equals or resolves to 127.0.0.1')
   .option('--verbose', 'enable airtap debug output')
   .option('--silly', 'enable all debug output')
 
diff --git a/lib/proxy-server.js b/lib/proxy-server.js
@@ -13,6 +13,7 @@ const http = require('http')
 const kLoopback = Symbol('kLoopback')
 const kServer = Symbol('kServer')
 const kUrl = Symbol('kUrl')
+const ip = '127.0.0.1'
 
 module.exports = class ProxyServer extends Nanoresource {
   constructor (manifest, cid, opts) {
@@ -21,7 +22,7 @@ module.exports = class ProxyServer extends Nanoresource {
     this.port = null
     this.url = null
 
-    this[kLoopback] = manifest.wants.loopback ? opts.loopback || 'airtap.local' : 'localhost'
+    this[kLoopback] = opts.loopback || (manifest.wants.loopback ? 'airtap.local' : 'localhost')
     this[kServer] = http.createServer()
 
     const self = this
@@ -56,8 +57,8 @@ module.exports = class ProxyServer extends Nanoresource {
   }
 
   _open (callback) {
-    lookup(this[kLoopback], { family: 4 }, (err, address) => {
-      if (err ? err.code === 'ENOTFOUND' : address !== '127.0.0.1') {
+    maybeLookup(this[kLoopback], { family: 4 }, (err, address) => {
+      if (err ? err.code === 'ENOTFOUND' : address !== ip) {
         return callback(new LoopbackError(this[kLoopback]))
       } else if (err) {
         return callback(transient(err))
@@ -84,9 +85,17 @@ module.exports = class ProxyServer extends Nanoresource {
   }
 }
 
+function maybeLookup (hostname, opts, callback) {
+  if (hostname === ip) {
+    process.nextTick(callback, null, ip)
+  } else {
+    lookup(hostname, opts, callback)
+  }
+}
+
 class LoopbackError extends Error {
   constructor (loopback) {
-    super(`Hostname '${loopback}' must resolve to 127.0.0.1. Please add an entry to your hosts file.`)
+    super(`Hostname '${loopback}' must resolve to ${ip}. Please add an entry to your hosts file.`)
 
     Object.defineProperty(this, 'name', { value: 'LoopbackError' })
     Object.defineProperty(this, 'expected', { value: true })
