Start adding Google Drive to demo app.

- Lengthy notes on all the Google docs and setup steps.
- Slightly janky flow with ngrok URLs for now, but works.
- As of now, I can do redirect login flow via Google's new JS and it all works.

NOTES.md

@@ -0,0 +1,62 @@
+# Goal
+
+This repo started off as a proof-of-concept that the WeScheme compiler
+and runtime could be separated from its UI in an easy-to-embed way with
+a simple React wrapper UI.
+
+My intention is to add back in the Google Drive integration so that this
+can form the foundation of a new version of the public WeScheme editor.
+
+# Scope
+
+- Core Google Drive Integration
+    - log in
+    - read/write Scheme files on Drive
+    - grant WeScheme access to images on Drive
+
+---
+
+# Notes
+
+For the sake of future maintainers, I am keeping this liveblog of notes
+of assumptions I make and docs I read as I try to get things working.
+
+- Ok, so how does Google want us to do authe/authn/API calls now?
+  - Reading Overview: https://developers.google.com/drive/api/guides/about-sdk
+  - Reading Quickstart: https://developers.google.com/drive/api/quickstart/js
+
+  - Project setup
+    - Make a new project in Google Cloud Console
+    - Search for "Google Drive API" and click "Enable"
+    - Set up authorization
+      - Create app and pick scopes
+        - In APIS & Services > OAuth Consent Screen: "Create app"
+        - Enter name, support email, domain, etc.
+        - Pick Scopes: "Google Drive API .. ./auth/docs"
+        - Add Test users by email (added myself and [email protected])
+      - Create OAuth client id
+        - APIs & Services > Credentials > + Create Credentials > OAuth Client Id
+        - Create new web client id. Add allowlisted domains.
+        - Note down client id and secret.
+      - Create api key
+        - APIs & Services > Credentials > + Create Credentials > API Key
+        - Note down API key. 
+
+  - Auth code
+    - Mostly stealing the code from the JS Quickstart
+      - Because we're using webpack, I had to rewrite all the callback functions from `function name() {...` to `window.name = function(){...`.
+    - At this point, Google code runs and correctly shows logged-out state.
+      - But, clicking to log in leads to an oauth redirect error (because we're on localhost)
+      - Let's fix this so we have a public URL in dev:
+        - Install ngrok (give a public https endpoint for local dev)
+          - Run `ngrok http https://localhost:8080` to expose local dev
+          - Find forwarding URL (some-long-id.ngrok.io) and use that
+        - Now webpack-dev-server fails with "Invalid Host Header"
+          - It doesn't like being proxied.
+          - So I had to add `disableHostCheck` in webpack.config.js
+        - Need to add ngrok url to both JS origin and redirect domains allowed on project (on the OAuth Client Id)
+
+    - At this point, the page appears, I can do the oauth redirect flow, accept permissions, and arrive back at a logged-in state.
+
+
+---

example/example.css

@@ -81,4 +81,10 @@
 .blocks-white-space.blocks-editing {
   font-weight: normal;
   margin: 15px;
+}
+
+nav {
+  display: flex;
+  justify-content: flex-end;
+  gap: 1em;
 }

example/example.js

@@ -65,4 +65,106 @@ function runBytecode() {
   } finally {
     reportIfNoOutput();
   }
+}
+
+
+
+///////////////////////////////////////////////////////////////////////////////
+// Google Drive experiment
+
+// TODO(developer): Set to client ID and API key from the Developer Console
+const CLIENT_ID = '887605636141-c61b646981pdr0j8u5t4i0l9lehdqrb6.apps.googleusercontent.com';
+const API_KEY = 'AIzaSyA7Wj4JqauQI8eTJ4nbCc-EkomT3gJ2sn0';
+
+// Discovery doc URL for APIs used by the quickstart
+const DISCOVERY_DOC = 'https://www.googleapis.com/discovery/v1/apis/drive/v3/rest';
+
+// Authorization scopes required by the API; multiple scopes can be
+// included, separated by spaces.
+const SCOPES = 'https://www.googleapis.com/auth/drive.metadata.readonly';
+
+let tokenClient;
+let gapiInited = false;
+let gisInited = false;
+
+document.getElementById('authorize_button').style.visibility = 'hidden';
+document.getElementById('signout_button').style.visibility = 'hidden';
+
+/**
+ * Callback after api.js is loaded.
+ */
+window.gapiLoaded = function() {
+  gapi.load('client', initializeGapiClient);
+}
+
+/**
+ * Callback after the API client is loaded. Loads the
+ * discovery doc to initialize the API.
+ */
+window.initializeGapiClient = async function() {
+  await gapi.client.init({
+    apiKey: API_KEY,
+    discoveryDocs: [DISCOVERY_DOC],
+  });
+  gapiInited = true;
+  maybeEnableButtons();
+}
+
+/**
+ * Callback after Google Identity Services are loaded.
+ */
+window.gisLoaded = function() {
+  tokenClient = google.accounts.oauth2.initTokenClient({
+    client_id: CLIENT_ID,
+    scope: SCOPES,
+    callback: '', // defined later
+  });
+  gisInited = true;
+  maybeEnableButtons();
+}
+
+/**
+ * Enables user interaction after all libraries are loaded.
+ */
+function maybeEnableButtons() {
+  if (gapiInited && gisInited) {
+    document.getElementById('authorize_button').style.visibility = 'visible';
+  }
+}
+
+/**
+ *  Sign in the user upon button click.
+ */
+window.handleAuthClick = function() {
+  tokenClient.callback = async (resp) => {
+    if (resp.error !== undefined) {
+      throw (resp);
+    }
+    document.getElementById('signout_button').style.visibility = 'visible';
+    document.getElementById('authorize_button').innerText = 'Refresh';
+    await listFiles();
+  };
+
+  if (gapi.client.getToken() === null) {
+    // Prompt the user to select a Google Account and ask for consent to share their data
+    // when establishing a new session.
+    tokenClient.requestAccessToken({prompt: 'consent'});
+  } else {
+    // Skip display of account chooser and consent dialog for an existing session.
+    tokenClient.requestAccessToken({prompt: ''});
+  }
+}
+
+/**
+ *  Sign out the user upon button click.
+ */
+window.handleSignoutClick = function() {
+  const token = gapi.client.getToken();
+  if (token !== null) {
+    google.accounts.oauth2.revoke(token.access_token);
+    gapi.client.setToken('');
+    document.getElementById('content').innerText = '';
+    document.getElementById('authorize_button').innerText = 'Authorize';
+    document.getElementById('signout_button').style.visibility = 'hidden';
+  }
 }

example/index.html

@@ -1,6 +1,11 @@
 <html>
   <body>
-    <h1>WeScheme as a Node Module</h1>
+    <nav>
+      <!--Google Auth buttons-->
+      <button id="authorize_button" onclick="handleAuthClick()">Authorize</button>
+      <button id="signout_button" onclick="handleSignoutClick()">Sign Out</button>
+    </nav>
+
     <div class="container">
       <div id="sourcecode" class="col">
         <p>Write scheme code here...</p>
@@ -17,5 +22,8 @@ <h1>WeScheme as a Node Module</h1>
     </div>
 
     <script src="build/example.js"></script>
+
+    <script async defer src="https://apis.google.com/js/api.js" onload="gapiLoaded()"></script>
+    <script async defer src="https://accounts.google.com/gsi/client" onload="gisLoaded()"></script>
   </body>
 </html>

webpack.config.js

@@ -30,5 +30,8 @@ module.exports = {
       { test: /\.css$/, loaders: ["style-loader", "css-loader"] },
       { test: /\.json$/, loaders: ["json-loader"] }
     ])
+  },
+  devServer: {
+    disableHostCheck: true,
   }
 }