refactor: split server into its own file (#224)

src/index.ts

@@ -1,22 +1,19 @@
 import {EventEmitter} from 'events';
-import {request, GaxiosResponse} from 'gaxios';
+import {URL} from 'url';
 import * as http from 'http';
-import enableDestroy = require('server-destroy');
-import finalhandler = require('finalhandler');
-import serveStatic = require('serve-static');
 import * as fs from 'fs';
 import * as util from 'util';
 import * as path from 'path';
-import * as marked from 'marked';
+
+import {request, GaxiosResponse} from 'gaxios';
 import PQueue, {DefaultAddOptions} from 'p-queue';
+import PriorityQueue from 'p-queue/dist/priority-queue';
 import * as globby from 'glob';
 
 import {getLinks} from './links';
-import {URL} from 'url';
-import PriorityQueue from 'p-queue/dist/priority-queue';
+import {startWebServer} from './server';
 
 const stat = util.promisify(fs.stat);
-const readFile = util.promisify(fs.readFile);
 const glob = util.promisify(globby);
 
 export interface CheckOptions {
@@ -85,12 +82,11 @@ export class LinkChecker extends EventEmitter {
     const hasHttpPaths = options.path.find(x => x.startsWith('http'));
     if (!hasHttpPaths) {
       const port = options.port || 5000 + Math.round(Math.random() * 1000);
-      server = await this.startWebServer(
+      server = await startWebServer(
         options.serverRoot!,
         port,
         options.markdown
       );
-      enableDestroy(server);
       for (let i = 0; i < options.path.length; i++) {
         if (options.path[i].startsWith('/')) {
           options.path[i] = options.path[i].slice(1);
@@ -244,44 +240,9 @@ export class LinkChecker extends EventEmitter {
         }
       }
     }
-
     return options;
   }
 
-  /**
-   * Spin up a local HTTP server to serve static requests from disk
-   * @param root The local path that should be mounted as a static web server
-   * @param port The port on which to start the local web server
-   * @param markdown If markdown should be automatically compiled and served
-   * @private
-   * @returns Promise that resolves with the instance of the HTTP server
-   */
-  private async startWebServer(root: string, port: number, markdown?: boolean) {
-    return new Promise<http.Server>((resolve, reject) => {
-      const serve = serveStatic(root);
-      const server = http
-        .createServer(async (req, res) => {
-          const pathParts = req.url!.split('/').filter(x => !!x);
-          if (pathParts.length > 0) {
-            const ext = path.extname(pathParts[pathParts.length - 1]);
-            if (markdown && ext.toLowerCase() === '.md') {
-              const filePath = path.join(path.resolve(root), req.url!);
-              const data = await readFile(filePath, {encoding: 'utf-8'});
-              const result = marked(data, {gfm: true});
-              res.writeHead(200, {
-                'content-type': 'text/html',
-              });
-              res.end(result);
-              return;
-            }
-          }
-          return serve(req, res, finalhandler(req, res) as () => void);
-        })
-        .listen(port, () => resolve(server))
-        .on('error', reject);
-    });
-  }
-
   /**
    * Crawl a given url with the provided options.
    * @pram opts List of options used to do the crawl

src/server.ts

@@ -0,0 +1,49 @@
+import * as http from 'http';
+import * as path from 'path';
+import * as util from 'util';
+import * as fs from 'fs';
+import * as marked from 'marked';
+import finalhandler = require('finalhandler');
+import serveStatic = require('serve-static');
+import enableDestroy = require('server-destroy');
+
+const readFile = util.promisify(fs.readFile);
+
+/**
+ * Spin up a local HTTP server to serve static requests from disk
+ * @param root The local path that should be mounted as a static web server
+ * @param port The port on which to start the local web server
+ * @param markdown If markdown should be automatically compiled and served
+ * @private
+ * @returns Promise that resolves with the instance of the HTTP server
+ */
+export async function startWebServer(
+  root: string,
+  port: number,
+  markdown?: boolean
+) {
+  return new Promise<http.Server>((resolve, reject) => {
+    const serve = serveStatic(root);
+    const server = http
+      .createServer(async (req, res) => {
+        const pathParts = req.url!.split('/').filter(x => !!x);
+        if (pathParts.length > 0) {
+          const ext = path.extname(pathParts[pathParts.length - 1]);
+          if (markdown && ext.toLowerCase() === '.md') {
+            const filePath = path.join(path.resolve(root), req.url!);
+            const data = await readFile(filePath, {encoding: 'utf-8'});
+            const result = marked(data, {gfm: true});
+            res.writeHead(200, {
+              'content-type': 'text/html',
+            });
+            res.end(result);
+            return;
+          }
+        }
+        return serve(req, res, finalhandler(req, res) as () => void);
+      })
+      .listen(port, () => resolve(server))
+      .on('error', reject);
+    enableDestroy(server);
+  });
+}