I am working to implement a Node.js webapp to be deployed on GCP App Engine.
Following the Node.js Bookshelf App sample, I did manage to implement a basic user authentication flow using the passport-google-oauth20 and retrieve basic profile information. I basically just got rid of what was not needed for my purposes
My custom code is available at: gist.github.com/vdenotaris/3a6dcd713e4c3ee3a973aa00cf0a45b0.
However, I would now like to consume a GCP Cloud Storage API to retrieve all the storage objects within a given buckets with the logged identity.
This should be possible by:
- adding a proper scope for the request.
- authenticating the REST requests using the user session token obtained via OAuth.
About the post-auth handler, the documentation says:
After you obtain credentials, you can store information about the
user. Passport.js automatically serializes the user to the session.
After the user’s information is in the session, you can make a couple
of middleware functions to make it easier to work with authentication.
// Middleware that requires the user to be logged in. If the user is not logged
// in, it will redirect the user to authorize the application and then return
// them to the original URL they requested.
function authRequired (req, res, next) {
if (!req.user) {
req.session.oauth2return = req.originalUrl;
return res.redirect('/auth/login');
}
next();
}
// Middleware that exposes the user's profile as well as login/logout URLs to
// any templates. These are available as `profile`, `login`, and `logout`.
function addTemplateVariables (req, res, next) {
res.locals.profile = req.user;
res.locals.login = `/auth/login?return=${encodeURIComponent(req.originalUrl)}`;
res.locals.logout = `/auth/logout?return=${encodeURIComponent(req.originalUrl)}`;
next();
}
But I do not see where the token is stored, how can I retrieve it and how to use it to consume a web-service (in my case, GCP storage).
I am not at all a node.js expert, so it would be nice having a bit more clarity on that: could someone explain me how to proceed in consuming a REST API using the logged user credentials (thus IAM/ACL privileges)?
Copyright Notice：Content Author:「vdenotaris」，Reproduced under the CC 4.0 BY-SA copyright license with a link to the original source and this disclaimer.
Link to original article：https://stackoverflow.com/questions/48968939/gcp-consume-a-rest-api-after-oauth-in-node-js