fix(http-server): correctly format IPv6 host in url

Enclose IPv6 host within `[]` in `url` property.

Author: Hage Yaapa

.travis.yml

@@ -30,3 +30,10 @@ matrix:
 branches:
   only:
     - master
+
+before_script:
+  # Add an IPv6 config - see the corresponding Travis issue
+  # https://github.com/travis-ci/travis-ci/issues/8361
+  - if [ "${TRAVIS_OS_NAME}" == "linux" ]; then
+      sudo sh -c 'echo 0 > /proc/sys/net/ipv6/conf/all/disable_ipv6';
+    fi

packages/http-server/src/http-server.ts

@@ -100,7 +100,11 @@ export class HttpServer {
    * URL of the HTTP / HTTPS server
    */
   public get url(): string {
-    return `${this._protocol}://${this.host}:${this.port}`;
+    let host = this.host;
+    if (this._address.family === 'IPv6') {
+      host = `[${host}]`;
+    }
+    return `${this._protocol}://${host}:${this.port}`;
   }
 
   /**

packages/http-server/test/integration/http-server.integration.ts

@@ -5,13 +5,21 @@
 import {HttpServer} from '../../';
 import {supertest, expect} from '@loopback/testlab';
 import * as makeRequest from 'request-promise-native';
-import {ServerRequest, ServerResponse} from 'http';
+import {ServerRequest, ServerResponse, get, IncomingMessage} from 'http';
 
 describe('HttpServer (integration)', () => {
   let server: HttpServer | undefined;
 
   afterEach(stopServer);
 
+  it('formats IPv6 url correctly', async () => {
+    server = new HttpServer(dummyRequestHandler, {host: '::1'});
+    await server.start();
+    expect(server.address!.family).to.equal('IPv6');
+    const response = await getAsync(server.url);
+    expect(response.statusCode).to.equal(200);
+  });
+
   it('starts server', async () => {
     server = new HttpServer(dummyRequestHandler);
     await server.start();
@@ -134,4 +142,10 @@ describe('HttpServer (integration)', () => {
     if (!server) return;
     await server.stop();
   }
+
+  function getAsync(url: string): Promise<IncomingMessage> {
+    return new Promise((resolve, reject) => {
+      get(url, resolve).on('error', reject);
+    });
+  }
 });