Using OpenID Connect (OIDC) and OAuth2 Client and Filters to manage access tokens

This guide explains how to use:

  • quarkus-oidc-client, quarkus-oidc-client-reactive-filter and quarkus-oidc-client-filter extensions to acquire and refresh access tokens from OpenId Connect and OAuth 2.0 compliant Authorization Servers such as Keycloak

  • quarkus-oidc-token-propagation extension to propagate the current Bearer or Authorization Code Flow access tokens

The access tokens managed by these extensions can be used as HTTP Authorization Bearer tokens to access the remote services.

OidcClient

Add the following Maven dependency:

<dependency>
    <groupId>io.quarkus</groupId>
    <artifactId>quarkus-oidc-client</artifactId>
</dependency>

quarkus-oidc-client extension provides a reactive io.quarkus.oidc.client.OidcClient which can be used to acquire and refresh tokens using SmallRye Mutiny Uni and Vert.x WebClient.

OidcClient is initialized at the build time with the IDP token endpoint URL which can be auto-discovered or manually configured and uses this endpoint to acquire access tokens using the token grants such as client_credentials or password and refresh the tokens using a refresh_token grant.

Token Endpoint Configuration

By default the token endpoint address is discovered by adding a /.well-known/openid-configuration path to the configured quarkus.oidc-client.auth-server-url.

For example, given this Keycloak URL:

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus

OidcClient will discover that the token endpoint URL is http://localhost:8180/auth/realms/quarkus/protocol/openid-connect/tokens.

Alternatively, if the discovery endpoint is not available or you would like to save on the discovery endpoint roundtrip, you can disable the discovery and configure the token endpoint address with a relative path value, for example:

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus
quarkus.oidc-client.discovery-enabled=false
# Token endpoint: http://localhost:8180/auth/realms/quarkus/protocol/openid-connect/tokens
quarkus.oidc-client.token-path=/protocol/openid-connect/tokens

Supported Token Grants

The main token grants which OidcClient can use to acquire the tokens are the client_credentials (default) and password grants.

Client Credentials Grant

Here is how OidcClient can be configured to use the client_credentials grant:

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus/
quarkus.oidc-client.client-id=quarkus-app
quarkus.oidc-client.credentials.secret=secret

The client_credentials grant allows to set extra parameters to the token request via quarkus.oidc-client.grant-options.client.<param-name>=<value>. Here is how to set the intended token recipient via the audience parameter:

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus/
quarkus.oidc-client.client-id=quarkus-app
quarkus.oidc-client.credentials.secret=secret
# 'client' is a shortcut for `client_credentials`
quarkus.oidc-client.grant.type=client
quarkus.oidc-client.grant-options.client.audience=https://example.com/api

Password Grant

Here is how OidcClient can be configured to use the password grant:

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus/
quarkus.oidc-client.client-id=quarkus-app
quarkus.oidc-client.credentials.secret=secret
quarkus.oidc-client.grant.type=password
quarkus.oidc-client.grant-options.password.username=alice
quarkus.oidc-client.grant-options.password.password=alice

It can be further customized using a quarkus.oidc-client.grant-options.password configuration prefix, similarly to how the client credentials grant can be customized.

Other Grants

OidcClient can also help with acquiring the tokens using the grants which require some extra input parameters which can not be captured in the configuration. These grants are refresh token (with the external refresh token), token exchange and authorization code.

Using the refresh_token grant which uses an out of band refresh token to acquire a new set of tokens will be required if the existing refresh token has been posted to the current Quarkus endpoint for it to acquire the access token. In this case OidcClient needs to be configured as follows:

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus/
quarkus.oidc-client.client-id=quarkus-app
quarkus.oidc-client.credentials.secret=secret
quarkus.oidc-client.grant.type=refresh

and then you can use OidcClient.refreshTokens method with a provided refresh token to get the access token.

Using the token exchange grant may be required if you are building a complex microservices application and would like to avoid the same Bearer token be propagated to and used by more than one service. Please see Token Propagation in MicroProfile RestClient client filter for more details.

Using OidcClient to support the authorization code grant might be required if for some reasons you can not use the Quarkus OpenId Connect extension to support Authorization Code Flow. If there is a very good reason for you to implement Authorization Code Flow then you can configure OidcClient as follows:

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus/
quarkus.oidc-client.client-id=quarkus-app
quarkus.oidc-client.credentials.secret=secret
quarkus.oidc-client.grant.type=code

and then you can use OidcClient.accessTokens method accepting a Map of extra properties and pass the current code and redirect_uri parameters to exchange the authorization code for the tokens.

Grant scopes

You may need to request that a specific set of scopes is associated with an issued access token. Use a dedicated quarkus.oidc-client.scopes list property, for example: quarkus.oidc-client.scopes=email,phone

Use OidcClient directly

One can use OidcClient directly as follows:

import javax.inject.PostConstruct;
import javax.inject.Inject;
import javax.ws.rs.GET;

import io.quarkus.oidc.client.OidcClient;
import io.quarkus.oidc.client.Tokens;

@Path("/service")
public class OidcClientResource {

    @Inject
    OidcClient client;

    volatile Tokens currentTokens;

    @PostConstruct
    public init() {
        currentTokens = client.getTokens().await().indefinitely();
    }

    @GET
    public String getResponse() {

        Tokens tokens = currentTokens;
        if (tokens.isAccessTokenExpired()) {
            // Add @Blocking method annotation if this code is used with Reactive RestClient
            tokens = client.refreshTokens(tokens.getRefreshToken()).await().indefinitely();
            currentTokens = tokens;
        }
        // Use tokens.getAccessToken() to configure MP RestClient Authorization header/etc
    }
}

Inject Tokens

You can inject Tokens which uses OidcClient internally. Tokens can be used to acquire the access tokens and refresh them if necessary:

import javax.inject.PostConstruct;
import javax.inject.Inject;
import javax.ws.rs.GET;

import io.quarkus.oidc.client.Tokens;

@Path("/service")
public class OidcClientResource {

    @Inject Tokens tokens;

    @GET
    public String getResponse() {
        //  Get the access token which may have been refreshed.
        String accessToken = tokens.getAccessToken();
        // Use the access token to configure MP RestClient Authorization header/etc
    }
}

Use OidcClients

io.quarkus.oidc.client.OidcClients is a container of OidcClients - it includes a default OidcClient and named clients which can be configured like this:

quarkus.oidc-client.client-enabled=false

quarkus.oidc-client.jwt-secret.auth-server-url=http://localhost:8180/auth/realms/quarkus/
quarkus.oidc-client.jwt-secret.client-id=quarkus-app
quarkus.oidc-client.jwt-secret.credentials.jwt.secret=AyM1SysPpbyDfgZld3umj1qzKObwVMkoqQ-EstJQLr_T-1qS0gZH75aKtMN3Yj0iPS4hcgUuTwjAzZr1Z9CAow

Note in this case the default client is disabled with a client-enabled=false property. The jwt-secret client can be accessed like this:

import javax.inject.Inject;
import javax.ws.rs.GET;
import javax.ws.rs.Path;

import io.quarkus.oidc.client.OidcClient;
import io.quarkus.oidc.client.OidcClients;

@Path("/clients")
public class OidcClientResource {

    @Inject
    OidcClients clients;

    @GET
    public String getResponse() {
        OidcClient client = clients.getClient("jwt-secret");
        // use this client to get the token
    }
}

If you also use OIDC multitenancy and each OIDC tenant has its own associated OidcClient then you can use a Vert.x RoutingContext tenantId attribute, for example:

import javax.inject.Inject;
import javax.ws.rs.GET;
import javax.ws.rs.Path;

import io.quarkus.oidc.client.OidcClient;
import io.quarkus.oidc.client.OidcClients;
import io.vertx.ext.web.RoutingContext;

@Path("/clients")
public class OidcClientResource {

    @Inject
    OidcClients clients;
    @Inject
    RoutingContext context;

    @GET
    public String getResponse() {
        String tenantId = context.get("tenantId");
        // named OIDC tenant and client configurations use the same key:
        OidcClient client = clients.getClient(tenantId);
        // use this client to get the token
    }
}

If you need you can also create new OidcClient programmatically like this:

import javax.inject.Inject;
import javax.ws.rs.GET;
import javax.ws.rs.Path;

import io.quarkus.oidc.client.OidcClient;
import io.quarkus.oidc.client.OidcClients;
import io.quarkus.oidc.client.OidcClientConfig;

import io.smallrye.mutiny.Uni;

@Path("/clients")
public class OidcClientResource {

    @Inject
    OidcClients clients;

    @GET
    public String getResponse() {
        OidcClientConfig cfg = new OidcClientConfig();
        cfg.setId("myclient");
        cfg.setAuthServerUrl("http://localhost:8081/auth/realms/quarkus/");
        cfg.setClientId("quarkus");
        cfg.getCredentials().setSecret("secret");
        Uni<OidcClient> client = clients.newClient(config);
        // use this client to get the token
    }
}

Inject named OidcClient and Tokens

In case of multiple configured OidcClients you can specify the OidcClient injection target by the extra qualifier @NamedOidcClient instead of working with OidcClients:

package io.quarkus.oidc.client;

import javax.inject.Inject;
import javax.ws.rs.GET;
import javax.ws.rs.Path;

@Path("/clients")
public class OidcClientResource {

    @Inject
    @NamedOidcClient("jwt-secret")
    OidcClient client;

    @GET
    public String getResponse() {
        // use client to get the token
    }
}

The same qualifier can be used to specify the OidcClient used for a Tokens injection:

@Provider
@Priority(Priorities.AUTHENTICATION)
@RequestScoped
public class OidcClientRequestCustomFilter implements ClientRequestFilter {

    @Inject
    @NamedOidcClient("jwt-secret")
    Tokens tokens;

    @Override
    public void filter(ClientRequestContext requestContext) throws IOException {
        requestContext.getHeaders().add(HttpHeaders.AUTHORIZATION, "Bearer " + tokens.getAccessToken());
    }
}

Use OidcClient in RestClient Reactive ClientFilter

Add the following Maven Dependency:

<dependency>
    <groupId>io.quarkus</groupId>
    <artifactId>quarkus-oidc-client-reactive-filter</artifactId>
</dependency>

Note it will also bring io.quarkus:quarkus-oidc-client.

quarkus-oidc-client-reactive-filter extension provides io.quarkus.oidc.client.filter.OidcClientRequestReactiveFilter.

It works similarly to the way OidcClientRequestFilter does (see Use OidcClient in MicroProfile RestClient client filter) - it uses OidcClient to acquire the access token, refresh it if needed, and set it as an HTTP Authorization Bearer scheme value. The difference is that it works with Reactive RestClient and implements a non-blocking client filter which does not block the current IO thread when acquiring or refreshing the tokens.

OidcClientRequestReactiveFilter delays an initial token acquisition until it is executed to avoid blocking an IO thread and it currently can only be registered with org.eclipse.microprofile.rest.client.annotation.RegisterProvider annotation:

import org.eclipse.microprofile.rest.client.annotation.RegisterProvider;
import org.eclipse.microprofile.rest.client.inject.RegisterRestClient;
import io.quarkus.oidc.client.reactive.filter.OidcClientRequestReactiveFilter;
import io.smallrye.mutiny.Uni;

@RegisterRestClient
@RegisterProvider(OidcClientRequestReactiveFilter.class)
@Path("/")
public interface ProtectedResourceService {

    @GET
    Uni<String> getUserName();
}

OidcClientRequestReactiveFilter uses a default OidcClient by default. A named OidcClient can be selected with a quarkus.oidc-client-reactive-filter.client-name configuration property.

Use OidcClient in RestClient ClientFilter

Add the following Maven Dependency:

<dependency>
    <groupId>io.quarkus</groupId>
    <artifactId>quarkus-oidc-client-filter</artifactId>
</dependency>

Note it will also bring io.quarkus:quarkus-oidc-client.

quarkus-oidc-client-filter extension provides io.quarkus.oidc.client.filter.OidcClientRequestFilter JAX-RS ClientRequestFilter which uses OidcClient to acquire the access token, refresh it if needed, and set it as an HTTP Authorization Bearer scheme value.

By default, this filter will get OidcClient to acquire the first pair of access and refresh tokens at its initialization time. If the access tokens are short-lived and refresh tokens are not available then the token acquisition should be delayed with quarkus.oidc-client.early-tokens-acquisition=false.

You can selectively register OidcClientRequestFilter by using either io.quarkus.oidc.client.filter.OidcClientFilter or org.eclipse.microprofile.rest.client.annotation.RegisterProvider annotations:

import org.eclipse.microprofile.rest.client.inject.RegisterRestClient;
import io.quarkus.oidc.client.filter.OidcClientFilter;

@RegisterRestClient
@OidcClientFilter
@Path("/")
public interface ProtectedResourceService {

    @GET
    String getUserName();
}

or

import org.eclipse.microprofile.rest.client.annotation.RegisterProvider;
import org.eclipse.microprofile.rest.client.inject.RegisterRestClient;
import io.quarkus.oidc.client.filter.OidcClientRequestFilter;

@RegisterRestClient
@RegisterProvider(OidcClientRequestFilter.class)
@Path("/")
public interface ProtectedResourceService {

    @GET
    String getUserName();
}

Alternatively, OidcClientRequestFilter can be registered automatically with all MP Rest or JAX-RS clients if quarkus.oidc-client-filter.register-filter=true property is set.

OidcClientRequestFilter uses a default OidcClient by default. A named OidcClient can be selected with a quarkus.oidc-client-filter.client-name configuration property.

Use Custom RestClient ClientFilter

If you prefer you can use your own custom filter and inject Tokens:

import io.quarkus.oidc.client.Tokens;

@Provider
@Priority(Priorities.AUTHENTICATION)
public class OidcClientRequestCustomFilter implements ClientRequestFilter {

    @Inject
    Tokens tokens;

    @Override
    public void filter(ClientRequestContext requestContext) throws IOException {
        requestContext.getHeaders().add(HttpHeaders.AUTHORIZATION, "Bearer " + tokens.getAccessToken());
    }
}

The Tokens producer will acquire and refresh the tokens, and the custom filter will decide how and when to use the token.

You can also inject named Tokens, see Inject named OidcClient and Tokens

Refreshing Access Tokens

OidcClientRequestReactiveFilter, OidcClientRequestFilter and Tokens producers will refresh the current expired access token if the refresh token is available. Additionally, quarkus.oidc-client.refresh-token-time-skew property can be used for a preemptive access token refreshment to avoid sending nearly expired access tokens which may cause HTTP 401 errors. For example if this property is set to 3S and the access token will expire in less than 3 seconds then this token will be auto-refreshed.

If the access token needs to be refreshed but no refresh token is available then an attempt will be made to acquire a new token using the configured grant such as client_credentials.

Please note that some OpenId Connect Providers will not return a refresh token in a client_credentials grant response. For example, starting from Keycloak 12 a refresh token will not be returned by default for client_credentials. The providers may also restrict a number of times a refresh token can be used.

OidcClient Authentication

OidcClient has to authenticate to the OpenId Connect Provider for the client_credentials and other grant requests to succeed. All the OIDC Client Authentication options are supported, for example:

client_secret_basic:

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus/
quarkus.oidc-client.client-id=quarkus-app
quarkus.oidc-client.credentials.secret=mysecret

or

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus/
quarkus.oidc-client.client-id=quarkus-app
quarkus.oidc-client.credentials.client-secret.value=mysecret

or with the secret retrieved from a CredentialsProvider:

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus/
quarkus.oidc-client.client-id=quarkus-app

# This is a key which will be used to retrieve a secret from the map of credentails returned from CredentialsProvider
quarkus.oidc-client.credentials.client-secret.provider.key=mysecret-key
# Set it only if more than one CredentialsProvider can be registered
quarkus.oidc-client.credentials.client-secret.provider.name=oidc-credentials-provider

client_secret_post:

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus/
quarkus.oidc-client.client-id=quarkus-app
quarkus.oidc-client.credentials.client-secret.value=mysecret
quarkus.oidc-client.credentials.client-secret.method=post

client_secret_jwt, signature algorithm is HS256:

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus/
quarkus.oidc-client.client-id=quarkus-app
quarkus.oidc-client.credentials.jwt.secret=AyM1SysPpbyDfgZld3umj1qzKObwVMkoqQ-EstJQLr_T-1qS0gZH75aKtMN3Yj0iPS4hcgUuTwjAzZr1Z9CAow

or with the secret retrieved from a CredentialsProvider, signature algorithm is HS256:

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus/
quarkus.oidc-client.client-id=quarkus-app

# This is a key which will be used to retrieve a secret from the map of credentials returned from CredentialsProvider
quarkus.oidc-client.credentials.jwt.secret-provider.key=mysecret-key
# Set it only if more than one CredentialsProvider can be registered
quarkus.oidc-client.credentials.jwt.secret-provider.name=oidc-credentials-provider

private_key_jwt with the PEM key file, signature algorithm is RS256:

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus/
quarkus.oidc-client.client-id=quarkus-app
quarkus.oidc-client.credentials.jwt.key-file=privateKey.pem

private_key_jwt with the key store file, signature algorithm is RS256:

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus/
quarkus.oidc-client.client-id=quarkus-app
quarkus.oidc-client.credentials.jwt.key-store-file=keystore.jks
quarkus.oidc-client.credentials.jwt.key-store-password=mypassword
quarkus.oidc-client.credentials.jwt.key-password=mykeypassword

# Private key alias inside the keystore
quarkus.oidc-client.credentials.jwt.key-id=mykeyAlias

Using client_secret_jwt or private_key_jwt authentication methods ensures that no client secret goes over the wire.

Additional JWT Authentication options

If either client_secret_jwt or private_key_jwt authentication methods are used then the JWT signature algorithm, key identifier and audience can be customized, for example:

# private_key_jwt client authentication

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus/
quarkus.oidc-client.client-id=quarkus-app
quarkus.oidc-client.credentials.jwt.key-file=privateKey.pem

# This is a token key identifier 'kid' header - set it if your OpenId Connect provider requires it.
# Note if the key is represented in a JSON Web Key (JWK) format with a `kid` property then
# using 'quarkus.oidc-client.credentials.jwt.token-key-id' is not necessary.
quarkus.oidc-client.credentials.jwt.token-key-id=mykey

# Use RS512 signature algorithm instead of the default RS256
quarkus.oidc-client.credentials.jwt.signature-algorithm=RS512

# The token endpoint URL is the default audience value, use the base address URL instead:
quarkus.oidc-client.credentials.jwt.audience=${quarkus.oidc-client.auth-server-url}

Testing

Start by adding the following dependencies to your test project:

<dependency>
    <groupId>io.quarkus</groupId>
    <artifactId>quarkus-junit5</artifactId>
    <scope>test</scope>
</dependency>
<dependency>
    <groupId>org.awaitility</groupId>
    <artifactId>awaitility</artifactId>
    <scope>test</scope>
</dependency>

Wiremock

Add the following dependencies to your test project:

<dependency>
    <groupId>com.github.tomakehurst</groupId>
    <artifactId>wiremock-jre8</artifactId>
    <scope>test</scope>
</dependency>

Write Wiremock based QuarkusTestResourceLifecycleManager, for example:

package io.quarkus.it.keycloak;

import static com.github.tomakehurst.wiremock.client.WireMock.matching;
import static com.github.tomakehurst.wiremock.core.WireMockConfiguration.wireMockConfig;

import java.util.HashMap;
import java.util.Map;

import com.github.tomakehurst.wiremock.WireMockServer;
import com.github.tomakehurst.wiremock.client.WireMock;
import com.github.tomakehurst.wiremock.core.Options.ChunkedEncodingPolicy;

import io.quarkus.test.common.QuarkusTestResourceLifecycleManager;

public class KeycloakRealmResourceManager implements QuarkusTestResourceLifecycleManager {
    private WireMockServer server;

    @Override
    public Map<String, String> start() {

        server = new WireMockServer(wireMockConfig().dynamicPort().useChunkedTransferEncoding(ChunkedEncodingPolicy.NEVER));
        server.start();

        server.stubFor(WireMock.post("/tokens")
                .withRequestBody(matching("grant_type=password&username=alice&password=alice"))
                .willReturn(WireMock
                        .aResponse()
                        .withHeader("Content-Type", "application/json")
                        .withBody(
                                "{\"access_token\":\"access_token_1\", \"expires_in\":4, \"refresh_token\":\"refresh_token_1\"}")));
        server.stubFor(WireMock.post("/tokens")
                .withRequestBody(matching("grant_type=refresh_token&refresh_token=refresh_token_1"))
                .willReturn(WireMock
                        .aResponse()
                        .withHeader("Content-Type", "application/json")
                        .withBody(
                                "{\"access_token\":\"access_token_2\", \"expires_in\":4, \"refresh_token\":\"refresh_token_1\"}")));


        Map<String, String> conf = new HashMap<>();
        conf.put("keycloak.url", server.baseUrl());
        return conf;
    }

    @Override
    public synchronized void stop() {
        if (server != null) {
            server.stop();
            server = null;
        }
    }
}

Prepare the REST test endpoints, you can have the test frontend endpoint which uses the injected MP REST client with a registered OidcClient filter to invoke on the downstream endpoint which echoes the token back, for example, see the integration-tests/oidc-client-wiremock in the main Quarkus repository.

Set application.properties, for example:

# Use 'keycloak.url' property set by the test KeycloakRealmResourceManager
quarkus.oidc-client.auth-server-url=${keycloak.url}
quarkus.oidc-client.discovery-enabled=false
quarkus.oidc-client.token-path=/tokens
quarkus.oidc-client.client-id=quarkus-service-app
quarkus.oidc-client.credentials.secret=secret
quarkus.oidc-client.grant.type=password
quarkus.oidc-client.grant-options.password.username=alice
quarkus.oidc-client.grant-options.password.password=alice

and finally write the test code. Given the Wiremock-based resource above, the first test invocation should return access_token_1 access token which will expire in 4 seconds. Use awaitility to wait for about 5 seconds, and now the next test invocation should return access_token_2 access token which confirms the expired access_token_1 access token has been refreshed.

Keycloak

If you work with Keycloak then you can use the same approach as described in the OpenId Connect Bearer Token Integration testing Keycloak section.

How to check the errors in the logs

Please enable io.quarkus.oidc.client.runtime.OidcClientImpl TRACE level logging to see more details about the token acquisition and refresh errors:

quarkus.log.category."io.quarkus.oidc.client.runtime.OidcClientImpl".level=TRACE
quarkus.log.category."io.quarkus.oidc.client.runtime.OidcClientImpl".min-level=TRACE

Please enable io.quarkus.oidc.client.runtime.OidcClientRecorder TRACE level logging to see more details about the OidcClient initialization errors:

quarkus.log.category."io.quarkus.oidc.client.runtime.OidcClientRecorder".level=TRACE
quarkus.log.category."io.quarkus.oidc.client.runtime.OidcClientRecorder".min-level=TRACE

Token Propagation

The quarkus-oidc-token-propagation extension provides two JAX-RS javax.ws.rs.client.ClientRequestFilter class implementations that simplify the propagation of authentication information. io.quarkus.oidc.token.propagation.AccessTokenRequestFilter propagates the Bearer token present in the current active request or the token acquired from the Authorization Code Flow, as the HTTP Authorization header’s Bearer scheme value. The io.quarkus.oidc.token.propagation.JsonWebTokenRequestFilter provides the same functionality, but in addition provides support for JWT tokens.

When you need to propagate the current Authorization Code Flow access token then the immediate token propagation will work well - as the code flow access tokens (as opposed to ID tokens) are meant to be propagated for the current Quarkus endpoint to access the remote services on behalf of the currently authenticated user.

However, the direct end to end Bearer token propagation should be avoided if possible. For example, Client → Service A → Service B where Service B receives a token sent by Client to Service A. In such cases Service B will not be able to distinguish if the token came from Service A or from Client directly. For Service B to verify the token came from Service A it should be able to assert a new issuer and audience claims.

Additionally, a complex application may need to exchange or update the tokens before propagating them. For example, the access context might be different when Service A is accessing Service B. In this case, Service A might be granted a narrow or a completely different set of scopes to access Service B.

The following sections show how AccessTokenRequestFilter and JsonWebTokenRequestFilter can help.

RestClient AccessTokenRequestFilter

AccessTokenRequestFilter treats all tokens as Strings and as such it can work with both JWT and opaque tokens.

You can selectively register AccessTokenRequestFilter by using either io.quarkus.oidc.token.propagation.AccessToken or org.eclipse.microprofile.rest.client.annotation.RegisterProvider, for example:

import org.eclipse.microprofile.rest.client.inject.RegisterRestClient;
import io.quarkus.oidc.token.propagation.AccessToken;

@RegisterRestClient
@AccessToken
@Path("/")
public interface ProtectedResourceService {

    @GET
    String getUserName();
}

or

import org.eclipse.microprofile.rest.client.annotation.RegisterProvider;
import org.eclipse.microprofile.rest.client.inject.RegisterRestClient;
import io.quarkus.oidc.token.propagation.AccessTokenRequestFilter;

@RegisterRestClient
@RegisterProvider(AccessTokenRequestFilter.class)
@Path("/")
public interface ProtectedResourceService {

    @GET
    String getUserName();
}

Alternatively, AccessTokenRequestFilter can be registered automatically with all MP Rest or JAX-RS clients if quarkus.oidc-token-propagation.register-filter property is set to true and quarkus.oidc-token-propagation.json-web-token property is set to false (which is a default value).

Exchange Token Before Propagation

If the current access token needs to be exchanged before propagation and you work with Keycloak or other OpenId Connect Provider which supports a Token Exchange token grant then you can configure AccessTokenRequestFilter like this:

quarkus.oidc-client.auth-server-url=http://localhost:8180/auth/realms/quarkus
quarkus.oidc-client.client-id=quarkus-app
quarkus.oidc-client.credentials.secret=secret
quarkus.oidc-client.grant.type=exchange
quarkus.oidc-client.grant-options.exchange.audience=quarkus-app-exchange

quarkus.oidc-token-propagation.exchange-token=true

Note AccessTokenRequestFilter will use OidcClient to exchange the current token and you can use quarkus.oidc-client.grant-options.exchange to set the additional exchange properties expected by your OpenId Connect Provider.

AccessTokenRequestFilter uses a default OidcClient by default. A named OidcClient can be selected with a quarkus.oidc-token-propagation.client-name configuration property.

RestClient JsonWebTokenRequestFilter

Using JsonWebTokenRequestFilter is recommended if you work with Bearer JWT tokens where these tokens can have their claims such as issuer and audience modified and the updated tokens secured (for example, re-signed) again. It expects an injected org.eclipse.microprofile.jwt.JsonWebToken and therefore will not work with the opaque tokens. Also, if your OpenId Connect Provider supports a Token Exchange protocol then it is recommended to use AccessTokenRequestFilter instead - as both JWT and opaque bearer tokens can be securely exchanged with AccessTokenRequestFilter.

JsonWebTokenRequestFilter makes it easy for Service A implementations to update the injected org.eclipse.microprofile.jwt.JsonWebToken with the new issuer and audience claim values and secure the updated token again with a new signature. The only difficult step is to ensure Service A has a signing key - it should be provisioned from a secure file system or from the remote secure storage such as Vault.

You can selectively register JsonWebTokenRequestFilter by using either io.quarkus.oidc.token.propagation.JsonWebToken or org.eclipse.microprofile.rest.client.annotation.RegisterProvider, for example:

import org.eclipse.microprofile.rest.client.inject.RegisterRestClient;
import io.quarkus.oidc.token.propagation.JsonWebToken;

@RegisterRestClient
@AccessToken
@Path("/")
public interface ProtectedResourceService {

    @GET
    String getUserName();
}

or

import org.eclipse.microprofile.rest.client.annotation.RegisterProvider;
import org.eclipse.microprofile.rest.client.inject.RegisterRestClient;
import io.quarkus.oidc.token.propagation.JsonWebTokenRequestFilter;

@RegisterRestClient
@RegisterProvider(JsonWebTokenTokenRequestFilter.class)
@Path("/")
public interface ProtectedResourceService {

    @GET
    String getUserName();
}

Alternatively, JsonWebTokenRequestFilter can be registered automatically with all MP Rest or JAX-RS clients if both quarkus.oidc-token-propagation.register-filter and quarkus.oidc-token-propagation.json-web-token properties are set to true.

Update Token Before Propagation

If the injected token needs to have its iss (issuer) and/or aud (audience) claims updated and secured again with a new signature then you can configure JsonWebTokenRequestFilter like this:

quarkus.oidc-token-propagation.secure-json-web-token=true
smallrye.jwt.sign.key.location=/privateKey.pem
# Set a new issuer
smallrye.jwt.new-token.issuer=http://frontend-resource
# Set a new audience
smallrye.jwt.new-token.audience=http://downstream-resource
# Override the existing token issuer and audience claims if they are already set
smallrye.jwt.new-token.override-matching-claims=true

As already noted above, please use AccessTokenRequestFilter if you work with Keycloak or OpenId Connect Provider which supports a Token Exchange protocol.

Testing

You can generate the tokens as described in OpenId Connect Bearer Token Integration testing section. Prepare the REST test endpoints, you can have the test frontend endpoint which uses the injected MP REST client with a registered token propagation filter to invoke on the downstream endpoint, for example, see the integration-tests/oidc-token-propagation in the main Quarkus repository.