[SOLVED] What is my google-signin-client

What is my google-signin-client_id

My web site used to have a link to let users login with their Google accounts in Open ID 2.0. Since 20.4.2015, this is no longer working, so I am trying to migrate to Google Sign-In.

This page: https://developers.google.com/identity/sign-in/web/sign-in#specify_your_apps_client_id

says:

Specify the client ID you created for your app in the Google Developers Console with the google-signin-client_id meta element.

I have no idea what my client ID is. In my Google Developers Console: https://console.developers.google.com/project

there is only a single, very old application I created with GoogleApp, which is not related at all to the website I am talking about. I tried using its project ID anyway, and got the following error after clicking the sign-in button:

401. That’s an error.

Error: invalid_client

The OAuth client was not found.
Request Details

    fetch_basic_profile=true
    scope=email profile openid
    response_type=permission
    redirect_uri=storagerelay://http/localhost?id=auth684995
    ss_domain=http://localhost
    client_id=imitatorgwt.apps.googleusercontent.com
    openid.realm=

That’s all we know.

What exactly should I write in the google-signin-client_id meta tag?

Solution

You need to create/configure a Google OAuth client. For detailed instructions on how to do so for Google OpenID2 -> OpenID Connect migration, check out Google's migration dev docs (in particular the pieces related to Google Developers Console).

A possible work-flow is:

Go to Google Developer Console.
Under "Select a project" on the top, select "Create new project" and fill the details.
In the dashboard on the left, go to "API & Auth" -> Credentials.
Under "OAuth", click "Create new client ID".
Under "Application type", select "Web application".
Under "Authorized Javascript origins", enter the URL(s) of your website. The "Authorized redirect URLs" are updated automatically.
Click "Create client ID".
The new client ID can be accessed any time by going to "Credentials" in the left dashboard. It looks something like this: "3453453452345-dfgjw3456u2094mlfg45p.apps.googleusercontent.com".

Hope that helps!

UPDATE

We have updated the referred documentation with instructions on how to create Google projects+client ids, see https://developers.google.com/identity/sign-in/web/devconsole-project. That should make things easier for developers in the future.

Again, thanks for reporting the problem!