Refactor utils.fetch to a module and mock it with nock

Add redirect support in utils.fetch

src/fetch.ts

@@ -0,0 +1,54 @@
+import {IncomingMessage, OutgoingHttpHeaders} from 'http';
+import * as https from 'https';
+import * as url from 'url';
+
+/**
+ * Function to fetch an URL
+ *
+ * @param input_url
+ * @param auth_token
+ */
+export async function fetch(
+  input_url: string,
+  auth_token?: string,
+  redirect_count = 5
+): Promise<Record<string, string>> {
+  const fetch_promise: Promise<Record<string, string>> = new Promise(
+    resolve => {
+      const url_object: url.UrlObject = new url.URL(input_url);
+      const headers: OutgoingHttpHeaders = {
+        'User-Agent': `Mozilla/5.0 (${process.platform} ${process.arch}) setup-php`
+      };
+      if (auth_token) {
+        headers.authorization = 'Bearer ' + auth_token;
+      }
+      const options: https.RequestOptions = {
+        hostname: url_object.hostname,
+        path: url_object.pathname,
+        headers: headers
+      };
+      const req = https.get(options, (res: IncomingMessage) => {
+        if (res.statusCode === 200) {
+          let body = '';
+          res.setEncoding('utf8');
+          res.on('data', chunk => (body += chunk));
+          res.on('end', () => resolve({data: `${body}`}));
+        } else if (
+          [301, 302, 303, 307, 308].includes(res.statusCode as number)
+        ) {
+          if (redirect_count > 0 && res.headers.location) {
+            fetch(res.headers.location, auth_token, redirect_count--).then(
+              resolve
+            );
+          } else {
+            resolve({error: `${res.statusCode}: Redirect error`});
+          }
+        } else {
+          resolve({error: `${res.statusCode}: ${res.statusMessage}`});
+        }
+      });
+      req.end();
+    }
+  );
+  return await fetch_promise;
+}