Iss #10 - Add support for private GL token when fetching specs

This change set is 1 half of the changeset, as currently the Jenkinsbuild doesn't allow for tokens to be embedded into the build. We will need tokens to be enabled to finish this feature.

src/index.js

@@ -31,14 +31,16 @@ const artificialSpecData = { items: [] };
  * @param {*} externalLocation the URL for the raw openapi spec file.
  * @param {*} localPath the location where the downloaded spec should be saved
  */
-async function pullExternalSpec(externalLocation, localPath) {
+async function pullExternalSpec(externalLocation, localPath, isPrivate = false) {
   let retries = 0;
   // retry 3 times before giving up
   while (retries < 3) {
     try {
       fs.writeFileSync(
         localPath,
-        await fetch(externalLocation).then(response => {
+        await fetch(externalLocation, {headers: {
+          "PRIVATE-TOKEN": isPrivate ? process.env.GITLAB_TOKEN : ''
+        }}).then(response => {
           if (!response.ok) {
             throw new Error(`HTTP error! Status: ${response.status}`);
           }
@@ -122,7 +124,7 @@ async function run() {
     console.log(`Retrieving openapi spec for ${specDisplayName}...`);
     // prepare the spec, fetching remote specs or copying the spec for processing
     if (isExternalSpec(specLocation)) {
-      await pullExternalSpec(specLocation, outputSpecLocation);
+      await pullExternalSpec(specLocation, outputSpecLocation, currentSpecDefinition['private'] === true);
     } else {
       fs.copyFileSync(potentialLocalSpecLocation, outputSpecLocation);
       console.log(`Copied local spec for ${specDisplayName} to output dir`);