feat(nginx): check dns entry exists before attempting ssl setup

refs #190
- adds check to ssl setup that ensures DNS entry exists before trying to get an SSL certificate

Author: acburdine

extensions/nginx/index.js

@@ -1,6 +1,7 @@
 'use strict';
 
 const fs = require('fs-extra');
+const dns = require('dns');
 const url = require('url');
 const path = require('path');
 const execa = require('execa');
@@ -107,6 +108,27 @@ class NginxExtension extends cli.Extension {
         let rootPath = path.resolve(ctx.instance.dir, 'system', 'nginx-root');
 
         return this.ui.listr([{
+            title: 'Checking DNS resolution',
+            task: () => {
+                return Promise.fromNode(cb => dns.lookup(parsedUrl.hostname, {family: 4}, cb)).catch((error) => {
+                    if (error.code !== 'ENOTFOUND') {
+                        // Some other error
+                        return Promise.reject(error);
+                    }
+
+                    // DNS entry has not populated yet, log an error and skip rest of the
+                    // ssl configuration
+                    let text = [
+                        'Uh-oh! It looks like your domain isn\'t set up correctly yet.',
+                        'Because of this, SSL setup won\'t work correctly. Once you\'ve set up your domain',
+                        'and pointed it at this server\'s IP, try running `ghost setup ssl` again.'
+                    ];
+
+                    this.ui.log(text.join(' '), 'yellow');
+                    return task.skip();
+                });
+            }
+        }, {
             title: 'Preparing nginx for SSL configuration',
             task: (ctx) => {
                 return argv.sslemail ? Promise.resolve({email: argv.sslemail}) : this.ui.prompt({

yarn.lock

@@ -1321,7 +1321,7 @@ glob-parent@^2.0.0:
   dependencies:
     is-glob "^2.0.0"
 
-[email protected], glob@^7.0.5:
+[email protected]:
   version "7.1.1"
   resolved "https://registry.yarnpkg.com/glob/-/glob-7.1.1.tgz#805211df04faaf1c63a3600306cdf5ade50b2ec8"
   dependencies:
@@ -1352,7 +1352,7 @@ glob@^6.0.1:
     once "^1.3.0"
     path-is-absolute "^1.0.0"
 
-glob@^7.0.3, glob@^7.1.2:
+glob@^7.0.3, glob@^7.0.5, glob@^7.1.2:
   version "7.1.2"
   resolved "https://registry.yarnpkg.com/glob/-/glob-7.1.2.tgz#c19c9df9a028702d678612384a6552404c636d15"
   dependencies:
@@ -1883,14 +1883,14 @@ js-tokens@^3.0.0:
   version "3.0.1"
   resolved "https://registry.yarnpkg.com/js-tokens/-/js-tokens-3.0.1.tgz#08e9f132484a2c45a30907e9dc4d5567b7f114d7"
 
-[email protected], [email protected]:
+[email protected]:
   version "3.6.1"
   resolved "https://registry.yarnpkg.com/js-yaml/-/js-yaml-3.6.1.tgz#6e5fe67d8b205ce4d22fad05b7781e8dadcc4b30"
   dependencies:
     argparse "^1.0.7"
     esprima "^2.6.0"
 
-js-yaml@^3.8.4:
+js-yaml@3.x, js-yaml@^3.8.4:
   version "3.8.4"
   resolved "https://registry.yarnpkg.com/js-yaml/-/js-yaml-3.8.4.tgz#520b4564f86573ba96662af85a8cafa7b4b5a6f6"
   dependencies: