📝 Add some comments

.clang-format

@@ -1,3 +1,4 @@
 BasedOnStyle: Google
+ColumnLimit: 90
 AlignConsecutiveAssignments: true
 KeepEmptyLinesAtTheStartOfBlocks: true

index.js

@@ -1,34 +1,14 @@
+//////////////////////////////////////////////////////////////////////////////////////////
+//                    This file is part of the Dynamic Badges Action                    //
+// It may be used under the terms of the MIT license. See the LICENSE file for details. //
+//                         Copyright: (c) 2020 Simon Schneegans                         //
+//////////////////////////////////////////////////////////////////////////////////////////
+
 const core = require('@actions/core');
 const http = require('https');
 
-try {
+// Performs an HTTP request and returns a Promise accordingly. See docs of
-
+// http.request() for the available options.
-  function updateGist(data) {
-    // Perform the actual request. The user agent is required as defined in
-    // https://developer.github.com/v3/#user-agent-required
-    const updateGistOptions = {
-      host: 'api.github.com',
-      path: '/gists/' + core.getInput('gistID'),
-      method: 'POST',
-      headers: {
-        'Content-Type': 'application/json',
-        'Content-Length': data.length,
-        'User-Agent': 'Schneegans',
-        'Authorization': 'token ' + core.getInput('auth'),
-      }
-    };
-
-    doRequest(updateGistOptions, data).then(res => {
-      if (res.statusCode < 200 || res.statusCode >= 400) {
-        core.setFailed(
-            'Failed to create gist, response status code: ' + res.statusCode +
-            ', status message: ' + res.statusMessage);
-      } else {
-        console.log('Success!');
-      }
-    });
-  }
-
 function doRequest(options, data) {
   return new Promise((resolve, reject) => {
     const req = http.request(options, res => {
@@ -54,10 +34,39 @@ try {
   });
 }
 
-  // This object will be stringified and uploaded to the gist. The
+// This uses the method above to update a gist with the given data. The user agent is
-  // schemaVersion, label and message attributes are always required. All others
+// required as defined in https://developer.github.com/v3/#user-agent-required
-  // are optional and added to the content object only if they are given to the
+function updateGist(data) {
-  // action.
+  const updateGistOptions = {
+    host: 'api.github.com',
+    path: '/gists/' + core.getInput('gistID'),
+    method: 'POST',
+    headers: {
+      'Content-Type': 'application/json',
+      'Content-Length': data.length,
+      'User-Agent': 'Schneegans',
+      'Authorization': 'token ' + core.getInput('auth'),
+    }
+  };
+
+  doRequest(updateGistOptions, data).then(res => {
+    if (res.statusCode < 200 || res.statusCode >= 400) {
+      core.setFailed(
+          'Failed to create gist, response status code: ' + res.statusCode +
+          ', status message: ' + res.statusMessage);
+    } else {
+      console.log('Success!');
+    }
+  });
+}
+
+// We wrap the entire action in a try / catch block so we can set it to "failed" if
+// something goes wrong.
+try {
+
+  // This object will be stringified and uploaded to the gist. The schemaVersion, label
+  // and message attributes are always required. All others are optional and added to the
+  // content object only if they are given to the action.
   let content = {
     schemaVersion: 1,
     label: core.getInput('label'),
@@ -158,9 +167,14 @@ try {
   const request =
       JSON.stringify({files: {[filename]: {content: JSON.stringify(content)}}});
 
+  // If "forceUpdate" is set to true, we can simply update the gist. If not, we have to
+  // get the gist data and compare it to the new value before.
   if (core.getBooleanInput('forceUpdate')) {
     updateGist(request);
+
   } else {
+
+    // Get the old gist.
     const getGistOptions = {
       host: 'api.github.com',
       path: '/gists/' + core.getInput('gistID'),
@@ -174,7 +188,7 @@ try {
 
     doRequest(getGistOptions, JSON.stringify({})).then(oldGist => {
       if (oldGist.statusCode < 200 || oldGist.statusCode >= 400) {
-        // print the error, but don't fail the action
+        // print the error, but don't fail the action.
         console.log(
             'Failed to get gist, response status code: ' + oldGist.statusCode +
             ', status message: ' + oldGist.statusMessage);
@@ -182,22 +196,20 @@ try {
 
       let shouldUpdate = true;
 
-      if (oldGist && oldGist.body && oldGist.body.files &&
+      if (oldGist && oldGist.body && oldGist.body.files && oldGist.body.files[filename]) {
-          oldGist.body.files[filename]) {
         const oldContent = oldGist.body.files[filename].content;
 
         if (oldContent === JSON.stringify(content)) {
-          console.log(
+          console.log(`Content did not change, not updating gist at ${filename}.`);
-              `Content did not change, not updating gist at ${filename}`);
           shouldUpdate = false;
         }
       }
 
       if (shouldUpdate) {
         if (oldGist.body.files[filename]) {
-          console.log(`Content changed, updating gist at ${filename}`);
+          console.log(`Content changed, updating gist at ${filename}.`);
         } else {
-          console.log(`Content didn't exist, creating gist at ${filename}`);
+          console.log(`Content didn't exist, creating gist at ${filename}.`);
         }
 
         updateGist(request);