Configure OpenID Connect with token exchange using Keycloak

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
   

decK is a CLI tool for managing Kong Gateway declaratively with state files. To complete this tutorial, install decK version 1.43 or later.

This guide uses deck gateway apply, which directly applies entity configuration to your Gateway instance. We recommend upgrading your decK installation to take advantage of this tool.

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 an identity provider (IdP). If you don’t have one, you can use Keycloak. The steps will be similar in other standard identity providers.

For this tutorial, you will need two clients. We’ll create both in Keycloak.

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 --features=token-exchange
   

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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 performs token exchange via keycloak:8080, and Keycloak must recognize the subject token’s iss claim (localhost:8080) as its own issuer.

2. Export your issuer URL, Keycloak host, and endpoint URLs to environment variables. For example, using Docker and the default master realm:

   export DECK_ISSUER='http://localhost:8080/realms/master'
   export DECK_JWKS_ENDPOINT='http://keycloak:8080/realms/master/protocol/openid-connect/certs'
   export DECK_TOKEN_ENDPOINT='http://keycloak:8080/realms/master/protocol/openid-connect/token'
   export KEYCLOAK_HOST='localhost'
   

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

   • DECK_ISSUER and KEYCLOAK_HOST use localhost because that’s how you access Keycloak from your machine.
   • DECK_JWKS_ENDPOINT and DECK_TOKEN_ENDPOINT 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_JWKS_ENDPOINT and DECK_TOKEN_ENDPOINT.

3. Open the admin console.

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

Create and configure first client

Create the first client:

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

Find the credentials for the first client:

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

5. Export the client ID and secret to environment variables:

   export DECK_CLIENT_ID_1='client-1'
   export DECK_CLIENT_SECRET_1='YOUR-CLIENT-SECRET'
   

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Create and configure second client

Create the second client:

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

Find the credentials for the second client:

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

5. Export the client ID and secret to environment variables:

   export DECK_CLIENT_ID_2='client-2'
   export DECK_CLIENT_SECRET_2='YOUR-CLIENT-SECRET'
   

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Configure client scopes

1. In the sidebar, open Client scopes, then click Create client scope.
2. Give the scope a unique name: add-client-2-as-audience.
3. Save the scope.
4. Click the Mappers tab.
5. Click Configure a new mapper and select Audience.
6. Configure the mapper:

Apply scope to client

1. In the sidebar, open Clients and click client-1.
2. Click Client scopes.
3. Click Add client scope.
4. In the modal, check add-client-2-as-audience.
5. Click Add and set the scope as “Optional”.

Set up user

1. Switch to the Users menu and add a user.

   In this guide, we’re going to use an example user named alex.

2. Open the user’s Credentials tab and add a password.

   In this guide, we’re going to use the example password doe.

3. Disable Temporary Password.
4. Save the credential.