Setup keycloak

Keycloak setup

docker run -p 8080:8080 -e KEYCLOAK_ADMIN=admin -e KEYCLOAK_ADMIN_PASSWORD=admin quay.io/keycloak/keycloak:latest start-dev

If you are using podman then just replace docker with podman in above bash command

the above command will pull latest keycloak and run it on localhost:8080
once the container is created, we can run it from docker desktop containers from next time. this will also prevent unnecessary container duplications.
navigate to above localhost and navigate to administration console and login as admin.

A realm can have multiple clients. frontend application needs a client along with realm to perform login actions.
To create a client, navigate to above realm from master dropdown.
click on Clients in side navigation and click on Create client. This opens a wizard:
- in 1st step, provide Client id: <hyphen-delimited-value> (in our case, React-auth)
- keep defaults in next steps and create client.
after client creation, navigate to Settings tab in above realm and set below things in Access Settings section:
- Valid redirect URIs: <frontend-application-protected-url> (in our case localhost:3000/about)
- Valid post logout redirect URIs: <frontend-application-default-url> (in our case localhost:3000/home)
- Web origins: <frontend-application-url> (in our case localhost:3000)

Each client can contain different roles which are assigned to different users. these are more like permissions that a user can have.
to create a role: navigate to Roles tab in above client and click on Create Role. provide a hyphen-seperated value

Realm roles are super set of client roles. A realm role can contain multiple client roles.
To create a realm role, navigate to above realm.
click on Realm roles in side bar navigation and click on Create role.
provide a hypen-seperated role name and save.
to assign client roles to a given realm role, navigate to above role from the list of realm roles.
- click on Action dropdown in top-right corner and click on Add associated roles
- this opens a modal dialog with filter dropdown, search and list of roles
- click on filter and select Filter by clients. this should show our client role which we created above along with defaults.
- select our new client role and save.
With this, we created a realm role and assigned some client roles to it.

A user in keycloak is associated to realm role which in turn have specific set of permissions (client roles).
To create a user, navigate to above realm and click on Users in side bar navigation.
Click on Add user. provide username, first name, last name and ignore email verified. save user.

To set a realm role, navigate to new user from users list.
navigate to Role mapping tab and click on Assign role
this opens a modal dialog with our realm role aloong with other default realm roles. select our realm role and save.
with this, we created the user with specific role which has specific permissions.