From dbdc26367af3cf566ce8f78592103f7890a15683 Mon Sep 17 00:00:00 2001
From: Andrew Goode <andrew@npmjs.com>
Date: Mon, 13 Jun 2016 21:22:52 -0400
Subject: [PATCH] feat: lookup host ip if none given (#14)

---
 README.md          | 41 +++++++++++++++++++++++++++++++++++++++--
 bin/which-cloud.js | 11 ++++++-----
 index.js           | 35 ++++++++++++++++++++++++-----------
 package.json       |  1 +
 test/cli.js        |  8 +++++---
 5 files changed, 75 insertions(+), 21 deletions(-)

diff --git a/README.md b/README.md
index eb497bd..bb9dbfe 100644
--- a/README.md
+++ b/README.md
@@ -7,16 +7,53 @@
 given an ip address, return which cloud provider it belongs to (EC2, GCE, etc)
 
 ```sh
-> which-cloud 104.196.27.39
-> gce
+$ which-cloud 104.196.27.39
+gce
+```
+
+if no ip is given, `which-cloud` will use the public ip of the current host
+
+```sh
+$ which-cloud
+AT&T Internet Services (SIS-80)
 ```
 
 ## Installing
 
+### CLI
+
 ```sh
 npm i which-cloud -g
 ```
 
+```sh
+which-cloud
+```
+
+### Module
+
+```sh
+npm i which-cloud --save
+```
+
+```js
+const whichCloud = require('which-cloud')
+```
+
+## API
+
+### `whichCloud([ip,] callback)`
+
+- `ip`: string, optional
+
+    Determine the cloud provider for this ip
+
+    If no ip is given, the public ip of the current host will be used
+
+- `callback`: function, required
+
+    Called with an `Error` or the determined cloud provider as a string
+
 ## Supported Clouds
 
 * Amazon Web Services (aws).
diff --git a/bin/which-cloud.js b/bin/which-cloud.js
index c62b856..bcf32f4 100755
--- a/bin/which-cloud.js
+++ b/bin/which-cloud.js
@@ -2,14 +2,12 @@
 
 const which = require('../')
 const argv = require('yargs')
-  .usage('$0 <ip>')
+  .usage('$0 [ip]')
   .help()
   .alias('help', 'h')
-  .demand(1, 'you must provide an ip to lookup')
   .argv
-const ip = argv._[0]
 
-which(ip, function (err, cloud) {
+function cb (err, cloud) {
   if (err) {
     console.log(which.default)
     process.exit(1)
@@ -17,4 +15,7 @@ which(ip, function (err, cloud) {
     console.log(cloud)
     process.exit(0)
   }
-})
+}
+
+if (argv._.length) which(argv._[0], cb)
+else which(cb)
diff --git a/index.js b/index.js
index ad54f52..29eaa85 100644
--- a/index.js
+++ b/index.js
@@ -6,6 +6,7 @@ const providers = [
   require('./lib/gce')
 ]
 const whois = require('./lib/whois')
+const publicIp = require('public-ip')
 
 function WhichCloud (ip, done) {
   var name = WhichCloud.default
@@ -25,19 +26,31 @@ function WhichCloud (ip, done) {
     return checkers
   }
 
-  parallel(checkersGenerator(ip), function (err) {
-    if (err) return done(err)
+  function runCheckers (ip, done) {
+    parallel(checkersGenerator(ip), function (err) {
+      if (err) return done(err)
 
-    if (name === WhichCloud.default) {
-      whois(ip).org(function (err, _name) {
-        if (err) return done(err)
-        if (_name) name = _name
+      if (name === WhichCloud.default) {
+        whois(ip).org(function (err, _name) {
+          if (err) return done(err)
+          if (_name) name = _name
+          return done(null, name)
+        })
+      } else {
         return done(null, name)
-      })
-    } else {
-      return done(null, name)
-    }
-  })
+      }
+    })
+  }
+
+  if (typeof ip === 'function') {
+    done = ip
+    publicIp.v4(function (err, hostIp) {
+      if (err) return done(err)
+      runCheckers(hostIp, done)
+    })
+  } else {
+    runCheckers(ip, done)
+  }
 }
 
 WhichCloud.default = 'unknown'
diff --git a/package.json b/package.json
index be23f5a..cb28ea3 100644
--- a/package.json
+++ b/package.json
@@ -40,6 +40,7 @@
     "gce-ips": "^1.0.2",
     "ip-range-check": "0.0.1",
     "lodash.assign": "^4.0.9",
+    "public-ip": "^1.2.0",
     "request": "^2.72.0",
     "whois": "^2.1.6",
     "xml2js": "^0.4.16",
diff --git a/test/cli.js b/test/cli.js
index fbb91b1..5468d55 100644
--- a/test/cli.js
+++ b/test/cli.js
@@ -1,13 +1,15 @@
 /* global describe, it */
 
-require('chai').should()
+const should = require('chai').should()
 
 const exec = require('child_process').exec
 
 describe('cli', function () {
-  it('displays help if no ip is provided', function (done) {
+  it('looks up host ip if no ip is provided', function (done) {
     exec('./bin/which-cloud.js', function (err, stdout, stderr) {
-      err.message.should.match(/you must provide an ip to lookup/)
+      should.not.exist(err)
+      stderr.should.be.empty
+      stdout.should.be.ok
       return done()
     })
   })