Configure OpenID Connect with multiple IdPs using a trusted issuer registry

This is a Konnect tutorial and requires a Konnect personal access token.

1. Create a new personal access token by opening the Konnect PAT page and selecting Generate Token.

2. Export your token to an environment variable:

   export KONNECT_TOKEN='YOUR_KONNECT_PAT'

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3. Run the quickstart script to automatically provision a Control Plane and Data Plane, and configure your environment:

   curl -Ls https://get.konghq.com/quickstart | bash -s -- -k $KONNECT_TOKEN --deck-output

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   This sets up a Konnect Control Plane named quickstart, provisions a local Data Plane, and prints out the following environment variable exports:

   export DECK_KONNECT_TOKEN=$KONNECT_TOKEN
   export DECK_KONNECT_CONTROL_PLANE_NAME=quickstart
   export KONNECT_CONTROL_PLANE_URL=https://us.api.konghq.com
   export KONNECT_PROXY_URL='http://localhost:8000'

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   Copy and paste these into your terminal to configure your session.

This tutorial requires Kong Gateway Enterprise. If you don’t have Kong Gateway set up yet, you can use the quickstart script with an enterprise license to get an instance of Kong Gateway running almost instantly.

1. Export your license to an environment variable:

    export KONG_LICENSE_DATA='LICENSE-CONTENTS-GO-HERE'

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2. Run the quickstart script:

   curl -Ls https://get.konghq.com/quickstart | bash -s -- -e KONG_LICENSE_DATA 

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   Once Kong Gateway is ready, you will see the following message:

    Kong Gateway Ready

To complete this tutorial, install decK. We recommend keeping decK up to date with the latest version (1.62.1).

decK is a CLI tool for managing Kong Gateway declaratively with state files. This guide uses deck gateway apply, which directly applies entity configuration to your Gateway instance.

You can check your current decK version with deck version.

For this tutorial, you’ll need Kong Gateway entities, like Gateway Services and Routes, pre-configured. These entities are essential for Kong Gateway to function but installing them isn’t the focus of this guide. Follow these steps to pre-configure them:

1. Run the following command:

   echo '
   _format_version: "3.0"
   services:
     - name: example-service
       url: http://httpbin.konghq.com/anything
   routes:
     - name: example-route
       paths:
       - "/anything"
       service:
         name: example-service
       protocols:
       - http
       - https
   ' | deck gateway apply -

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To learn more about entities, you can read our entities documentation.

This tutorial requires two identity providers (IdPs). If you don’t have them, you can simulate two separate IdPs using two Keycloak realms. The steps will be similar with other standard identity providers.

Install and run Keycloak

1. Install Keycloak (version 26 or later) on your platform.

   For example, you can use the Keycloak Docker image. The following command attaches Keycloak to the same network as Kong Gateway so that the OIDC plugin can reach it:

    docker run -p 127.0.0.1:8080:8080 \
      --name keycloak \
      --network kong-quickstart-net \
      -e KC_BOOTSTRAP_ADMIN_USERNAME=admin \
      -e KC_BOOTSTRAP_ADMIN_PASSWORD=admin \
      -e KC_HOSTNAME=http://localhost:8080 \
      quay.io/keycloak/keycloak start-dev

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   The parameter KC_HOSTNAME=http://localhost:8080 ensures Keycloak always uses localhost:8080 as its token issuer regardless of which URL it’s accessed through. This is required because Kong Gateway runs inside Docker and accesses Keycloak via the container name keycloak:8080, but the iss claim in issued tokens must use localhost:8080 for the plugin to recognize them.

2. Export your environment variables. For example, using Docker and the master and realm-b realms:

   export DECK_REALM_A_ISSUER='http://localhost:8080/realms/master'
   export DECK_REALM_B_ISSUER='http://localhost:8080/realms/realm-b'
   export DECK_REALM_A_JWKS='http://keycloak:8080/realms/master/protocol/openid-connect/certs'
   export DECK_REALM_B_JWKS='http://keycloak:8080/realms/realm-b/protocol/openid-connect/certs'
   export KEYCLOAK_HOST='localhost'

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   Because we’re using Docker for this demo, we must configure a few networking parameters:

   • DECK_REALM_A_ISSUER and DECK_REALM_B_ISSUER use localhost because that’s how you access Keycloak from your machine.
   • DECK_REALM_A_JWKS and DECK_REALM_B_JWKS use the container name keycloak because Kong Gateway runs inside Docker and reaches Keycloak over the shared kong-quickstart-net network.

   In your own setup, especially running outside of a container, you may not need DECK_REALM_A_JWKS and DECK_REALM_B_JWKS.

3. Open the Keycloak admin console.

   The default URL is http://localhost:8080/admin/master/console/.

4. Log in with the credentials you defined when you launched Keycloak. For this example, the credentials are username admin and password admin.

Configure the first IdP

The master realm acts as the first identity provider. Create a client for realm-a:

1. In the sidebar, open Clients, then click Create client.
2. Configure the client:

Find the credentials for client-a:

1. In the sidebar, open Clients, and select client-a.
2. Click the Credentials tab.
3. Set Client Authenticator to Client ID and Secret.
4. Copy the Client Secret.

5. Export the client secret to an environment variable:

   export DECK_CLIENT_A_SECRET='YOUR-CLIENT-SECRET'

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Configure the second IdP

Create a second Keycloak realm to simulate a second identity provider:

1. In the sidebar click Manage realms.
2. Click Create realm.
3. Set Realm name to realm-b.
4. Click Create.

Create a client for realm-b:

1. Make sure you’re in the realm-b realm (check the top-left dropdown).
2. In the sidebar, open Clients, then click Create client.
3. Configure the client:

Find the credentials for client-b:

1. In the sidebar, open Clients, and select client-b.
2. Open the Credentials tab.
3. Set Client Authenticator to Client ID and Secret.
4. Copy the Client Secret.

5. Export the client secret to an environment variable:

   export DECK_CLIENT_B_SECRET='YOUR-CLIENT-SECRET'

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