OpenID Connect: Client credentials grant in header - Plugin

Client credentials grant in header

Configure the OpenID Connect plugin with the client credentials grant.

Here’s how the client credentials grant works:

 
sequenceDiagram
    autonumber
    participant client as Client 
(e.g. mobile app)
    participant kong as API Gateway 
(Kong)
    participant idp as IdP 
(e.g. Keycloak)
    participant httpbin as Upstream 
(upstream service,
 e.g. httpbin)
    activate client
    activate kong
    client->>kong: Service with
basic authentication
    deactivate client
    kong->>kong: load basic
authentication credentials
    activate idp
    kong->>idp: IdP/token
with client credentials
    deactivate kong
    idp->>idp: authenticate client
    activate kong
    idp->>kong: return tokens
    deactivate idp
    kong->>kong: verify tokens
    activate httpbin
    kong->>httpbin: request with access token
    httpbin->>kong: response
    deactivate httpbin
    activate client
    kong->>client: response
    deactivate kong
    deactivate client

In this example, the plugin will only accept client credentials sent in a header, but you can also set the client_credentials_param_type parameter to body, query, or any combination of these values.

For a complete example of authenticating with client credentials using Keycloak, see the tutorial for configuring OpenID Connect with the client credentials grant.

Note: Setting config.client_auth to client_secret_post lets you easily test the connection to your IdP, but we recommend using a more secure auth method in production. You can use any of the supported client auth methods.

Prerequisites

A configured identity provider (IdP)

Environment variables

ISSUER: The issuer authentication URL for your IdP. For example, if you’re using Keycloak as your IdP, the issuer URL looks like this: http://localhost:8080/realms/example-realm
CLIENT_ID: The client ID that the plugin uses when it calls authenticated endpoints of the IdP.
CLIENT_SECRET: The client secret needed to connect to your IdP.

Set up the plugin

Add this section to your declarative configuration file:

_format_version: "3.0"
plugins:
  - name: openid-connect
    config:
      issuer: ${{ env "DECK_ISSUER" }}
      client_id:
      - ${{ env "DECK_CLIENT_ID" }}
      client_secret:
      - ${{ env "DECK_CLIENT_SECRET" }}
      client_auth:
      - client_secret_post
      auth_methods:
      - client_credentials
      client_credentials_param_type:
      - header

Make the following request:

curl -i -X POST http://localhost:8001/plugins/ \
    --header "Accept: application/json" \
    --header "Content-Type: application/json" \
    --data '
    {
      "name": "openid-connect",
      "config": {
        "issuer": "'$ISSUER'",
        "client_id": [
          "'$CLIENT_ID'"
        ],
        "client_secret": [
          "'$CLIENT_SECRET'"
        ],
        "client_auth": [
          "client_secret_post"
        ],
        "auth_methods": [
          "client_credentials"
        ],
        "client_credentials_param_type": [
          "header"
        ]
      }
    }
    '

Make the following request:

curl -X POST https://{region}.api.konghq.com/v2/control-planes/{controlPlaneId}/core-entities/plugins/ \
    --header "accept: application/json" \
    --header "Content-Type: application/json" \
    --header "Authorization: Bearer $KONNECT_TOKEN" \
    --data '
    {
      "name": "openid-connect",
      "config": {
        "issuer": "'$ISSUER'",
        "client_id": [
          "'$CLIENT_ID'"
        ],
        "client_secret": [
          "'$CLIENT_SECRET'"
        ],
        "client_auth": [
          "client_secret_post"
        ],
        "auth_methods": [
          "client_credentials"
        ],
        "client_credentials_param_type": [
          "header"
        ]
      }
    }
    '

Make sure to replace the following placeholders with your own values:

region: Geographic region where your Kong Konnect is hosted and operates.
controlPlaneId: The id of the control plane.
KONNECT_TOKEN: Your Personal Access Token (PAT) associated with your Konnect account.

See the Konnect API reference to learn about region-specific URLs and personal access tokens.

echo "
apiVersion: configuration.konghq.com/v1
kind: KongClusterPlugin
metadata:
  name: openid-connect
  namespace: kong
  annotations:
    kubernetes.io/ingress.class: kong
  labels:
    global: 'true'
config:
  issuer: '$ISSUER'
  client_id:
  - '$CLIENT_ID'
  client_secret:
  - '$CLIENT_SECRET'
  client_auth:
  - client_secret_post
  auth_methods:
  - client_credentials
  client_credentials_param_type:
  - header
plugin: openid-connect
" | kubectl apply -f -

Prerequisite: Configure your Personal Access Token

terraform {
  required_providers {
    konnect = {
      source  = "kong/konnect"
    }
  }
}

provider "konnect" {
  personal_access_token = "$KONNECT_TOKEN"
  server_url            = "https://us.api.konghq.com/"
}

Add the following to your Terraform configuration to create a Konnect Gateway Plugin:

resource "konnect_gateway_plugin_openid_connect" "my_openid_connect" {
  enabled = true

  config = {
    issuer = var.issuer
    client_id = [var.client_id]
    client_secret = [var.client_secret]
    client_auth = ["client_secret_post"]
    auth_methods = ["client_credentials"]
    client_credentials_param_type = ["header"]
  }

  control_plane_id = konnect_gateway_control_plane.my_konnect_cp.id
}

This example requires the following variables to be added to your manifest. You can specify values at runtime by setting TF_VAR_name=value.

variable "client_secret" {
  type = string
}

Add this section to your declarative configuration file:

_format_version: "3.0"
plugins:
  - name: openid-connect
    service: serviceName|Id
    config:
      issuer: ${{ env "DECK_ISSUER" }}
      client_id:
      - ${{ env "DECK_CLIENT_ID" }}
      client_secret:
      - ${{ env "DECK_CLIENT_SECRET" }}
      client_auth:
      - client_secret_post
      auth_methods:
      - client_credentials
      client_credentials_param_type:
      - header

Make sure to replace the following placeholders with your own values:

serviceName|Id: The id or name of the service the plugin configuration will target.

Make the following request:

curl -i -X POST http://localhost:8001/services/{serviceName|Id}/plugins/ \
    --header "Accept: application/json" \
    --header "Content-Type: application/json" \
    --data '
    {
      "name": "openid-connect",
      "config": {
        "issuer": "'$ISSUER'",
        "client_id": [
          "'$CLIENT_ID'"
        ],
        "client_secret": [
          "'$CLIENT_SECRET'"
        ],
        "client_auth": [
          "client_secret_post"
        ],
        "auth_methods": [
          "client_credentials"
        ],
        "client_credentials_param_type": [
          "header"
        ]
      }
    }
    '

Make sure to replace the following placeholders with your own values:

serviceName|Id: The id or name of the service the plugin configuration will target.

Make the following request:

curl -X POST https://{region}.api.konghq.com/v2/control-planes/{controlPlaneId}/core-entities/services/{serviceId}/plugins/ \
    --header "accept: application/json" \
    --header "Content-Type: application/json" \
    --header "Authorization: Bearer $KONNECT_TOKEN" \
    --data '
    {
      "name": "openid-connect",
      "config": {
        "issuer": "'$ISSUER'",
        "client_id": [
          "'$CLIENT_ID'"
        ],
        "client_secret": [
          "'$CLIENT_SECRET'"
        ],
        "client_auth": [
          "client_secret_post"
        ],
        "auth_methods": [
          "client_credentials"
        ],
        "client_credentials_param_type": [
          "header"
        ]
      }
    }
    '

Make sure to replace the following placeholders with your own values:

region: Geographic region where your Kong Konnect is hosted and operates.
controlPlaneId: The id of the control plane.
KONNECT_TOKEN: Your Personal Access Token (PAT) associated with your Konnect account.
serviceId: The id of the service the plugin configuration will target.

See the Konnect API reference to learn about region-specific URLs and personal access tokens.

echo "
apiVersion: configuration.konghq.com/v1
kind: KongPlugin
metadata:
  name: openid-connect
  namespace: kong
  annotations:
    kubernetes.io/ingress.class: kong
config:
  issuer: '$ISSUER'
  client_id:
  - '$CLIENT_ID'
  client_secret:
  - '$CLIENT_SECRET'
  client_auth:
  - client_secret_post
  auth_methods:
  - client_credentials
  client_credentials_param_type:
  - header
plugin: openid-connect
" | kubectl apply -f -

Next, apply the KongPlugin resource by annotating the service resource:

kubectl annotate -n kong service SERVICE_NAME konghq.com/plugins=openid-connect

Prerequisite: Configure your Personal Access Token

terraform {
  required_providers {
    konnect = {
      source  = "kong/konnect"
    }
  }
}

provider "konnect" {
  personal_access_token = "$KONNECT_TOKEN"
  server_url            = "https://us.api.konghq.com/"
}

Add the following to your Terraform configuration to create a Konnect Gateway Plugin:

resource "konnect_gateway_plugin_openid_connect" "my_openid_connect" {
  enabled = true

  config = {
    issuer = var.issuer
    client_id = [var.client_id]
    client_secret = [var.client_secret]
    client_auth = ["client_secret_post"]
    auth_methods = ["client_credentials"]
    client_credentials_param_type = ["header"]
  }

  control_plane_id = konnect_gateway_control_plane.my_konnect_cp.id
  service = {
    id = konnect_gateway_service.my_service.id
  }
}

This example requires the following variables to be added to your manifest. You can specify values at runtime by setting TF_VAR_name=value.

variable "client_secret" {
  type = string
}

Add this section to your declarative configuration file:

_format_version: "3.0"
plugins:
  - name: openid-connect
    route: routeName|Id
    config:
      issuer: ${{ env "DECK_ISSUER" }}
      client_id:
      - ${{ env "DECK_CLIENT_ID" }}
      client_secret:
      - ${{ env "DECK_CLIENT_SECRET" }}
      client_auth:
      - client_secret_post
      auth_methods:
      - client_credentials
      client_credentials_param_type:
      - header

Make sure to replace the following placeholders with your own values:

routeName|Id: The id or name of the route the plugin configuration will target.

Make the following request:

curl -i -X POST http://localhost:8001/routes/{routeName|Id}/plugins/ \
    --header "Accept: application/json" \
    --header "Content-Type: application/json" \
    --data '
    {
      "name": "openid-connect",
      "config": {
        "issuer": "'$ISSUER'",
        "client_id": [
          "'$CLIENT_ID'"
        ],
        "client_secret": [
          "'$CLIENT_SECRET'"
        ],
        "client_auth": [
          "client_secret_post"
        ],
        "auth_methods": [
          "client_credentials"
        ],
        "client_credentials_param_type": [
          "header"
        ]
      }
    }
    '

Make sure to replace the following placeholders with your own values:

routeName|Id: The id or name of the route the plugin configuration will target.

Make the following request:

curl -X POST https://{region}.api.konghq.com/v2/control-planes/{controlPlaneId}/core-entities/routes/{routeId}/plugins/ \
    --header "accept: application/json" \
    --header "Content-Type: application/json" \
    --header "Authorization: Bearer $KONNECT_TOKEN" \
    --data '
    {
      "name": "openid-connect",
      "config": {
        "issuer": "'$ISSUER'",
        "client_id": [
          "'$CLIENT_ID'"
        ],
        "client_secret": [
          "'$CLIENT_SECRET'"
        ],
        "client_auth": [
          "client_secret_post"
        ],
        "auth_methods": [
          "client_credentials"
        ],
        "client_credentials_param_type": [
          "header"
        ]
      }
    }
    '

Make sure to replace the following placeholders with your own values:

region: Geographic region where your Kong Konnect is hosted and operates.
controlPlaneId: The id of the control plane.
KONNECT_TOKEN: Your Personal Access Token (PAT) associated with your Konnect account.
routeId: The id of the route the plugin configuration will target.

See the Konnect API reference to learn about region-specific URLs and personal access tokens.

echo "
apiVersion: configuration.konghq.com/v1
kind: KongPlugin
metadata:
  name: openid-connect
  namespace: kong
  annotations:
    kubernetes.io/ingress.class: kong
config:
  issuer: '$ISSUER'
  client_id:
  - '$CLIENT_ID'
  client_secret:
  - '$CLIENT_SECRET'
  client_auth:
  - client_secret_post
  auth_methods:
  - client_credentials
  client_credentials_param_type:
  - header
plugin: openid-connect
" | kubectl apply -f -

Next, apply the KongPlugin resource by annotating the httproute or ingress resource:

kubectl annotate -n kong httproute  konghq.com/plugins=openid-connect

kubectl annotate -n kong ingress  konghq.com/plugins=openid-connect

Prerequisite: Configure your Personal Access Token

terraform {
  required_providers {
    konnect = {
      source  = "kong/konnect"
    }
  }
}

provider "konnect" {
  personal_access_token = "$KONNECT_TOKEN"
  server_url            = "https://us.api.konghq.com/"
}

Add the following to your Terraform configuration to create a Konnect Gateway Plugin:

resource "konnect_gateway_plugin_openid_connect" "my_openid_connect" {
  enabled = true

  config = {
    issuer = var.issuer
    client_id = [var.client_id]
    client_secret = [var.client_secret]
    client_auth = ["client_secret_post"]
    auth_methods = ["client_credentials"]
    client_credentials_param_type = ["header"]
  }

  control_plane_id = konnect_gateway_control_plane.my_konnect_cp.id
  route = {
    id = konnect_gateway_route.my_route.id
  }
}

This example requires the following variables to be added to your manifest. You can specify values at runtime by setting TF_VAR_name=value.

variable "client_secret" {
  type = string
}

OpenID Connect

Client credentials grant in header

Prerequisites

Environment variables

Set up the plugin

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