tutorial: implement hostname resolve

bitfinexcom · Dec 21, 2017 · 18bde1c · 18bde1c
1 parent b429ff5
commit 18bde1c
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diff --git a/README.md b/README.md
@@ -28,26 +28,28 @@ node worker.js --env=development --wtype=wrk-dns-service-api --apiPort 1337
 
 ## Grenache API
 
-### action: 'getHelloWorld'
+### action: 'getHostname'
 
   - `args`: &lt;Array&gt;
     - `0`: &lt;Object&gt;
-      - `name`: &lt;String&gt; Name to greet
+      - `ip`: &lt;String&gt; Ip to resolve
 
 **Response:**
 
-  - &lt;String&gt; The Greeting
+  - &lt;Array&gt;
+    - `0`: &lt;String&gt; Ip that was resolved
+    - `1`: &lt;Array&gt; Hostnames
 
 **Example Payload:**
 
 ```js
-args: [ { name: 'Paolo' } ]
+args: [ { ip: '8.8.8.8' } ]
 ```
 
 **Example Response:**
 
 ```js
-'Hello Paolo'
+[ '8.8.8.8', [ 'google-public-dns-a.google.com' ] ]
 ```
 
 Example: [example.js](example.js)
diff --git a/example.js b/example.js
@@ -14,8 +14,8 @@ const peer = new Peer(link, {})
 peer.init()
 
 const query = {
-  action: 'getHelloWorld',
-  args: [ { name: 'Paolo' } ]
+  action: 'getHostname',
+  args: [ { ip: '8.8.8.8' } ]
 }
 
 peer.request('dns:service', query, { timeout: 10000 }, (err, data) => {

diff --git a/workers/loc.api/service.dns.js b/workers/loc.api/service.dns.js
@@ -1,5 +1,7 @@
 'use strict'
 
+const dns = require('dns')
+
 const { Api } = require('bfx-wrk-api')
 
 class dnsService extends Api {
@@ -8,6 +10,16 @@ class dnsService extends Api {
     return space
   }
 
+  getHostname (space, args, cb) {
+    const ip = args.ip
+    if (!ip) return cb(new Error('ERR_ARGS_NO_IP'))
+
+    dns.reverse(ip, (err, res) => {
+      if (err) return cb(err)
+
+      cb(null, [ip, res])
+    })
+  }
 }
 
 module.exports = dnsService