add Google auth plugin

plugins/talk-plugin-google-auth/server/passport.js

@@ -0,0 +1,41 @@
+const GoogleStrategy = require('passport-google-oauth2').Strategy;
+const UsersService = require('services/users');
+const { ValidateUserLogin } = require('services/passport');
+let { ROOT_URL } = require('config');
+
+if (ROOT_URL[ROOT_URL.length - 1] !== '/') {
+  ROOT_URL += '/';
+}
+
+module.exports = passport => {
+  if (
+    process.env.TALK_GOOGLE_CLIENT_ID &&
+    process.env.TALK_GOOGLE_CLIENT_SECRET &&
+    process.env.TALK_ROOT_URL
+  ) {
+    passport.use(
+      new GoogleStrategy(
+        {
+          clientID: process.env.TALK_GOOGLE_CLIENT_ID,
+          clientSecret: process.env.TALK_GOOGLE_CLIENT_SECRET,
+          callbackURL: `${ROOT_URL}api/v1/auth/google/callback`,
+          passReqToCallback: true,
+        },
+        async (req, accessToken, refreshToken, profile, done) => {
+          let user;
+          try {
+            user = await UsersService.findOrCreateExternalUser(profile);
+          } catch (err) {
+            return done(err.toString());
+          }
+
+          return ValidateUserLogin(profile, user, done);
+        }
+      )
+    );
+  } else if (process.env.NODE_ENV !== 'test') {
+    throw new Error(
+      'Google cannot be enabled, missing one of TALK_GOOGLE_CLIENT_ID, TALK_GOOGLE_CLIENT_SECRET, TALK_ROOT_URL'
+    );
+  }
+};

plugins/talk-plugin-google-auth/server/router.js

@@ -0,0 +1,29 @@
+module.exports = router => {
+  const { passport, HandleAuthPopupCallback } = require('services/passport');
+
+  /**
+   * Google auth endpoint, this will redirect the user immediatly to google
+   * for authorization.
+   */
+  router.get(
+    '/api/v1/auth/google',
+    passport.authenticate('google', {
+      display: 'popup',
+      authType: 'rerequest',
+      scope: ['profile'],
+    })
+  );
+
+  /**
+   * Google callback endpoint, this will send the user a html page designed to
+   * send back the user credentials upon sucesfull login.
+   */
+  router.get('/api/v1/auth/google/callback', (req, res, next) => {
+    // Perform the google login flow and pass the data back through the opener.
+    passport.authenticate(
+      'google',
+      { session: false },
+      HandleAuthPopupCallback(req, res, next)
+    )(req, res, next);
+  });
+};