OpenID Connect SSO configuration

Bonita can be configured to use the OpenID Connect (OIDC) protocol to provide single sign-on (SSO), as long as you already have an OpenID Connect Identity Provider server up and running (IdP). OIDC is an extension of OAuth 2.0. Contrary to the SSO support of SAML2, both Bonita Web User Interface and Bonita REST API can be secured and accessed using the OIDC/OAuth protocols (versus just the Web User Interface for SAML2).

For Enterprise, Performance, Efficiency, and Teamwork editions only.

This information applies to a Bonita platform deployed from a bundle, not to the Engine launched from Bonita Studio. <BUNDLE_HOME> refers to the root directory of the bundle.

OpenID Connect configuration is at tenant level. Each tenant can use a different authentication method (over OIDC or not).

Bonita uses Keycloak OIDC Service client adapter. It has been extended to support other OIDC providers than Keycloak.
Authentication in Bonita with OIDC has been tested with both Keycloak server and Google’s OpenID Connect endpoint.

OpenID Connect overview for Bonita

Only the Authorization Code Flow of OpenID Connect is supported. Not the Implicit Flow.

This is an overview that describes the steps of the authentication process on a Bonita bundle configured as an OIDC client:

Authentication over OIDC

Here are some details about the Bonita OIDC module, it is composed of:

  • A servlet filter that intercepts all the requests to Bonita Application pages

    It checks if the user is already logged in on Bonita

    • If already logged in => Allow the access

    • If not logged in => Redirect to IdP (with scope, client Id, redirect URI, and code response type)

  • An Implementation of the Authentication Manager extension point that retrieves the authentication information in the requests to log in to Bonita engine with the right credentials.

The username attribute of Bonita user accounts should match one of the claims of the JWT token returned in the OIDC provider response (by default the prefered_username is used but you can change the configuration to use another claim). If some users need to be able to log in without having an account on the IdP, you can authorize it by activating an option in the file authenticationManager-config.properties (see 2. below). Users will then be able to log in using the Bonita login page (/login.jsp) as long as they have a Bonita account and their password is different from their username.
You can configure Bonita engine to create the accounts on the fly in the database once a user accessing Bonita has been authenticated with the IdP (see the configuration of bonita-tenant-sp-custom.properties in the 3rd section of the next chapter).

Configure Bonita Bundle for OIDC

You need to execute the following actions in the folder of each tenant for which you want to support authentication over OpenID Connect. If you want this configuration to also apply to each tenant created later, make sure to also perform those actions in the template tenant configuration folder: <BUNDLE_HOME>/setup/platform_conf/current/tenant_template_* (if you have not started the Bonita bundle yet, the files are located in <BUNDLE_HOME>/setup/platform_conf/initial/tenant_template_*)

The bundle already contains the files needed to use OIDC with Bonita platform. To configure Bonita for OIDC:

  1. If you do not already have one:

    1. Download a Subscription edition bundle from the Customer Service Center

    2. Configure it as needed

    3. Run it a first time, so that the first default tenant is created (TENANT_ID = 1)

    4. Stop it and run setup[.sh][.bat] pull to retrieve current configuration before modifying the configuration files below

  2. In the tenant_portal folder of each existing tenant: <BUNDLE_HOME>/setup/platform_conf/current/tenants/<TENANT_ID>/tenant_portal, edit the authenticationManager-config.properties as follows:

        -->  #auth.AuthenticationManager = org.bonitasoft.console.common.server.auth.impl.standard.StandardAuthenticationManagerImpl
             (...)
        -->  auth.AuthenticationManager = org.bonitasoft.console.common.server.auth.impl.oidc.OIDCAuthenticationManagerImpl
        -->  oidc.filter.active = true
        -->  oidc.auth.standard.allowed = true
        -->  oidc.logout.url = http://localhost:9090/auth/realms/bonita/protocol/openid-connect/logout
        -->  oidc.logout.url.redirectQuery = ?redirect_uri={encodedRedirectUri}
        -->  auth.tenant.admin.username = install
        -->  auth.passphrase = BonitaBPM
             (...)
        -->  auth.tenant.standard.whitelist = william.jobs
             (...)
        -->  logout.link.hidden=true

    Make sure to set the right tenant admin username. It is recommended to also replace the value of the passphrase (property auth.passphrase) which is used by the engine to verify the authentication request. The value must be the same as in the file bonita-tenant-sp-custom.properties.
    If you need users to be able to log in without having an account on the IDP, you can authorize it by setting the property oidc.auth.standard.allowed to true. Users will then be able to log in using the Bonita login page (/login.jsp) provided they have a Bonita account and their password is different from their username.
    If only a limited group of users need to bypass OIDC authentication method you can restrain it by setting the property oidc.auth.standard.allowed to false and setting the property auth.tenant.standard.whitelist with the list of authorized usernames (comma separated). Otherwise you can keep it commented.

  3. In the tenant_engine folder of each existing tenant: <BUNDLE_HOME>/setup/platform_conf/current/tenants/<TENANT_ID>/tenant_engine/ edit the file bonita-tenant-sp-custom.properties as follows:

             # Authentication service to use. Some are natively provided:
             # authenticationService
             #   * binded to bonita authentication mode
             #   * impl: org.bonitasoft.engine.authentication.impl.AuthenticationServiceImpl
             # jaasAuthenticationService
             #   * to use JAAS
             #   * impl: com.bonitasoft.engine.authentication.impl.JAASGenericAuthenticationServiceImpl
             #   * this is the one to configure SSO over CAS (CAS properties to be defined hereafter
             # noAuthenticationService
             #   * does no authentication on the engine side
             #   * impl: com.bonitasoft.engine.authentication.impl.NoAuthenticationServiceImpl
             # passphraseOrPasswordAuthenticationService
             #   * Used by SSO implementations, login only if a passphrase is valid, or if a username/password is valid.
             #   * Requires PassphraseOrPasswordAuthenticationService bean to be uncommented in bonita-tenant-sp-custom.xml
             #   * impl: com.bonitasoft.engine.authentication.impl.PassphraseOrPasswordAuthenticationService
             # you can provide your own implementation in bonita-tenant-sp-custom.xml and refer to the bean name of your choice
        -->  authentication.service.ref.name=passphraseOrPasswordAuthenticationService
    
             # If authentication.service.ref.name equals "passphraseOrPasswordAuthenticationService",
             # you need to configure the following passphrase
        -->  authentication.service.ref.passphrase=BonitaBPM
    
             # Create users on the fly, when they are missing from bonita but authenticated by the SSO. The user will belong to the group and role specified below.
             #authentication.passphraseOrPasswordAuthenticationService.createMissingUser.enable=true
             #authentication.passphraseOrPasswordAuthenticationService.createMissingUser.defaultMembershipGroupPath=/ACME/HR
             #authentication.passphraseOrPasswordAuthenticationService.createMissingUser.defaultMembershipRoleName=member
    
             # CAS authentication delegate : enables the user, providing login/password,
             # to be logged in automatically against CAS web application
             # To be used in conjunction with the generic authentication service configured with CAS (jaasAuthenticationService)
             #authenticator.delegate=casAuthenticatorDelegate
             #authentication.delegate.cas.server.url.prefix=http://ip_address:port
             #authentication.delegate.cas.service.url=http://ip_address:port/bonita/loginservice

    It is recommended to also replace the value of the passphrase (property auth.passphrase). The value must be the same as in the file authenticationManager-config.properties updated previously.

    If you want Bonita engine to create the accounts on the fly once a user accessing Bonita has been authenticated with the IdP, you can uncomment the property authentication.passphraseOrPasswordAuthenticationService.createMissingUser.enable (and set its value to true) as well as the next 2 properties to add a default membership to each user account:

    • authentication.passphraseOrPasswordAuthenticationService.createMissingUser.defaultMembershipGroupPath specify the group in which every user account created on the fly will be added (the full group path is needed)

    • authentication.passphraseOrPasswordAuthenticationService.createMissingUser.defaultMembershipRoleName specify the role to use to create the membership

    Activating this option means any user authorized by the IdP to access Bonita will have an account created automatically in Bonita Database.
  4. In the tenant_portal folder of each existing tenant: <BUNDLE_HOME>/setup/platform_conf/current/tenants/<TENANT_ID>/tenant_portal,
    edit the file keycloak-oidc.json to setup Bonita webapp as an OIDC client working with your OIDC provider.

     {
       "realm": "master",
       "resource": "bonita",
       "auth-server-url": "http://localhost:9090/auth",
       "auth-url": "{auth-server-url}/realms/{realm-name}/protocol/openid-connect/auth",
       "token-url": "{auth-server-url}/realms/{realm-name}/protocol/openid-connect/token",
       "logout-url": "{auth-server-url}/realms/{realm-name}/protocol/openid-connect/logout",
       "token-issuer-uri": "{auth-server-url}/realms/{realm-name}",
       "user-info-url": "{auth-server-url}/realms/{realm-name}/protocol/openid-connect/userinfo",
       "jwks-url": "{auth-server-url}/realms/{realm-name}/protocol/openid-connect/certs",
       "jwt-access-token": true,
       "scope-values": "openid profile email",
       "save-target-url-in-state": true,
       "ssl-required": "external",
       "principal-attribute": "preferred_username",
       "public-client": false,
       "autodetect-bearer-only": true,
       "enable-cors": true,
       "cors-allowed-methods": "POST, PUT, DELETE, GET",
       "credentials" : {
         "secret" : "put-your-secret-here"
       }
     }
    • The property realm is only required if you use a Keycloak server as OIDC provider or if you want to benefit from the templating in the *-url properties ({realm-name} will be replaced with the realm value). If you use a Keycloak server, make sure you set it with the name of the realm in which your Bonita OIDC client is/will be created.

    • resource is the OIDC client Id given to your Bonita installation. You can change it if you want but you need to provide it to your OIDC provider.

    • auth-server-url is the base URL of the OIDC provider server. All other service endpoints URL values can reuse this base URL with the placeholder{auth-server-url}.

    • auth-url needs to be set with the URL of your OIDC provider Authorization endpoint. It can be prefixed with {auth-server-url} to only indicate the path of the end point or be a full absolute URL. This property is specific to Bonita OIDC module and is not supported/documented by Keycloak.

    • token-url needs to be set with the URL of your OIDC provider Token endpoint. It can be prefixed with {auth-server-url} to only indicate the path of the end point or be a full absolute URL. This property is specific to Bonita OIDC module and is not supported/documented by Keycloak.

    • logout-url needs to be set with the URL of your OIDC provider Logout endpoint. It can be prefixed with {auth-server-url} to only indicate the path of the end point or be a full absolute URL. This property is specific to Bonita OIDC module and is not supported/documented by Keycloak.

    • token-issuer-uri needs to be set with the URL that will be used as issuer in the JWT tokens (iss claim). It can be prefixed with {auth-server-url} to only indicate the path of the issuer URI or be a full absolute URI. For example using Google’s OIDC provider, the issuer is https://accounts.google.com. This property is specific to Bonita OIDC module and is not supported/documented by Keycloak.

    • user-info-url needs to be set with the URL of your OIDC provider userInfo end point. It is only used when accessing a resource with a Bearer Authorization header with an access token that is opaque (not a JWT) and cannot be validated or used to retrieve the logged in user claims. It can be prefixed with {auth-server-url} to only indicate the path of the end point or be a full absolute URL. This property is specific to Bonita OIDC module and is not supported/documented by Keycloak.

    • jwks-url needs to be set with the URL of your OIDC provider JSON Web Key Set endpoint. It can be prefixed with {auth-server-url} to only indicate the path of the end point or be a full absolute URL. For example with Google as OIDC provider, this URL is https://www.googleapis.com/oauth2/v3/certs. This property is specific to Bonita OIDC module and is not supported/documented by Keycloak.

    • jwt-access-token indicates if the access token is a JWT. If false, it will be considered by Bonita OIDC module as an opaque token and its validation and retrieval of the logged in user principal name will be delegated to the userInfo endpoint (see user-info-url). This property is specific to Bonita OIDC module and is not supported/documented by Keycloak.

    • scope-values can be used to set the value of the scope parameter sent to the OIDC provider in the authentication request. The scope value openid is automatically added if it is no present, but you can add other scope values like email or profile depending on your OIDC provider configuration and the claims you need in the JWTs to match Bonita username. This property is specific to Bonita OIDC module and is not supported/documented by Keycloak.

    • Some OpenID Connect providers do not support having a pattern of valid redirecting URIs. It is the case with Google’s for example. With those providers you can use the state parameter to pass the target URL (the URL you initially requested and want to be redirected to). In order to do that, set the property save-target-url-in-state to true. When you do that, the redirect_URI query parameter will always be the same. Its default value is the path /bonita/keycloak on Bonita server, but you can set a different value using the property redirect-uri-path. Make sure this URL is part of the valid redirect URIs in you OIDC provider configuration for the Bonita client. When save-target-url-in-state is set to false or not present, the redirect_URI query parameter is used to save the target URL. Those properties are specific to Bonita OIDC module and are not supported/documented by Keycloak.

    • the ssl-required property value may need to be changed if Bonita Runtime and the IdP are not both accessed via HTTPS. Possible values for this property are: all, external, and none. For all, all requests must come in via HTTPS. For external, only non-private IP addresses must come over via HTTPS. For none, no requests are required to come over via HTTPS.

    • the principal-attribute value indicates the OIDC ID Token attribute/claim (preferred_username, sub, email, name, etc…​) to use to be considered as user identifier in the client application. It should match the username in Bonita.

    • public-client needs to be set to false if the OIDC provider requires the client requests to be authenticated (with a client secret for example). In this case you also need to use the credentials property. If this property is set to true, then no client Authentication header will be sent to the OIDC provider.

    • enable-cors is required only if you want to be able to use Bonita REST API from a web application located on a different domain from your Bonita installation’s. It comes with additional options cors-max-age, cors-allowed-methods, cors-allowed-headers, cors-exposed-headers. You can check Keycloak client adpter config documentation for more information.

    • credentials you can set it with an object containing either a secret,jwt or secret-jwt attribute if Bonita client is configured with a confidential access type in the OIDC provider (public-client is set to false). See Keycloak’s client authentication documentation for more information.

    • Some additional properties no present in the default file can be useful:

      • connection-pool-size for the pool of connection to the OIDC provider server (20 by default)

      • truststore path to a truststore file for OIDC provider servers requiring HTTPS. It should contain one or more trusted host certificates or certificate authorities. You can create this truststore by extracting the public certificate of the OIDC server’s SSL keystore. This property is mandatory if you OIDC provider requires HTTPS unless you set disable-trust-manager property to true. If the truststore requires a password, you also need to add the property truststore-password.

      • client-keystore path to a keystore file containing client certificate for two-way SSL when the OIDC client adapter makes HTTPS requests to the OIDC provider server. You also need to add the properties client-keystore-password (password for the client keystore) and client-key-password (password for the client’s key).

      • verify-token-audience can be set to true to verify, when accessing the REST API with a Bearer authentication, that the access token audience (aud claim) contains the client Id (resource property). In Authorization Code Flow, this verification is always done and cannot be disabled.

      • redirect-rewrite-rules can be used to modify the path section of the redirect URI sent to the OIDC provider with the authentication or code exchange requests. By default the URI sent is the request URI as seen by Bonita OIDC module, but if Bonita is behind a reverse proxy for example, the path of the URI seen by Bonita OIDC module may be the one of the internal URI used by the reverse proxy and not the one of URI the OIDC provider needs to redirect the user agent (web browser) to. The value of this property is an object where each attribute key is a regular expression to which the Redirect URI path is to be matched and the attribute value is the replacement String. The other parts of the URI like the protocol, domain, port or query string cannot be modified. Here is an example removing "/bonita" from the redirect URI:

          "redirect-rewrite-rules" : {
            "^/bonita/(.*)$" : "/$1"
          }

More configuration options can be found in Keycloak official documentation

Once your Identity Provider is correctly configured (see the section Configure the Identity Provider), try to access any Bonita Application page, an app page or a form URL (or just ?tenant=<tenantId>) and make sure that you are redirected to your Identity Provider to log in (unless you are already logged in).
Note that if you try to access http://<bundle host>:<port>/bonita/login.jsp, then you won’t be redirected to the OIDC provider’s authentication end point since this page needs to be accessible for the tenant administrator (or another user if you set the property oidc.auth.standard.allowed to true) to be able to log in without an account on the Identity Provider.

If your Bonita platform is behind a reverse proxy or a load balancer, You need to make sure the reverse proxy / load balancer is configured to include the correct headers for the host (and the protocol if needed) to the requests and the application server is configured to use these headers (it is usually the case by default).
This is required so that HttpServletRequest.getRequestURL returns the URL used by the user and not the internal URL used by the reverse proxy.
For example, if you are running Apache >=2.0.31 as reverse proxy, this configuration is controlled by the property ProxyPreserveHost that will override the Host: header.
This can also be achieved by configuring the load balancer / reverse proxy so that it sets the X-Forwarded- HTTP headers. For example :

    X-Forwarded-Proto: https
    X-Forwarded-Host: your.bonita.external.url.host

If you need more fine tuning or if you cannot update the reverse proxy configuration, you can consult the official documentation for Tomcat

Configure the Identity Provider

Your OIDC identity provider (IdP) should declare an OIDC Service Provider named (or whose client Id is) bonita (or the value of the resource property set in the file keycloack-oidc.json of Bonita bundle if it is different ) with the following configuration or the equivalent depending on your IdP:

    "clientId": "bonita",
    "clientSecret": "your client secret",
    "baseUrl": "<your bonita server URL>", (for example http://my.company.domain:8080/bonita)
    "adminUrl": "<your bonita server URL>/keycloak", (for example http://my.company.domain:8080/bonita/keycloak)
  this URL is used by the server to communicate directly with Bonita service provider (to push revocation policies for example))
    "clientAuthenticatorType": "client-secret", (can also be "signed JWT" or "signed JWT with client secret" depending on your use case and security policies)
    "redirectUris": [
      "http://my.company.domain:8080/*" (those are the valid redirect URLs)
    ],
    "bearerOnly": false,
    "publicClient": false,
    "consentRequired": false, (or true if you want the users to have to consent if a third party app uses Bonita REST API for example)
    "standardFlowEnabled": true, (this is for the authorization code flow)
    "implicitFlowEnabled": false, (Bonita OIDC module does not support implicit flow)
    "directAccessGrantsEnabled": true, (or false if you don't want to use the Resource Owner Credentials Grant type to access the REST API)
    "frontchannelLogout": true,

If you use "Signed JWT" as the method of authentication for your bonita client you must either provide the public key or the certificate of the Bonita server to the OIDC provider or a JWKS URL where the OIDC provider can download the client’s public keys. Bonita OIDC module provides this service at the following URL: "http://my.company.domain:8080/bonita/k_jwks"
You may also define some access or ID token signature and encryption mechanism. In this case, make sure to update Bonita bundle configuration file keycloack-oidc.json accordingly.

If the IdP declares a redirect URI, it might override the target URL (redirect_URI parameter) set by the Bonita OIDC module in the request, and you may always end up on the same page after logging in. In that case, try to remove the redirect URI from your OIDC provider’s Bonita client configuration. Bonita supports redirection to the URL initially requested after logging in on the IdP, provided the IdP doesn’t force this URL.

Configure logout behaviour

If your Bonita platform is configured to manage authentication over OIDC, when users log out of Bonita Runtime, they do not log out of the OIDC Identity Provider (IdP). Therefore they are not logged out of all applications that are using the OIDC provider. To avoid this, you have two options :

Hide the logout button of the Bonita Layout

This is the most commonly used solution. Users are logged in as long as they don’t close their web browser and their session does not time out. To do this, set the logout.link.hidden option to true in authenticationManager-config.properties located in <BUNDLE_HOME>/setup/platform_conf/initial/tenant_template_portal for not initialized platform or <BUNDLE_HOME>/setup/platform_conf/current/tenant_template_portal and <BUNDLE_HOME>/setup/platform_conf/current/tenants/[TENANT_ID]/tenant_portal/.

When a user logs out from the IdP directly, Bonita Runtime’s session will remain active. The user’s session time to live will be reset to the configured session timeout value upon each user interaction with the server.

Setup Bonita platform for OIDC logout

Global logout allows to log out from the OIDC provider as well as all the registered Service Providers when logging out from Bonita platform. This is sometimes required for example if users are on public computers. As OIDC Providers do not necessarily support single logout and have different ways of handling it (there are several OIDC Single Logout methods), Bonita only offers OIDC logout through an OIDC logout URL that the IpP should provide and support. To setup Bonita for OIDC logout:

  1. Set the value of the property oidc.logout.url with your OIDC provider logout URL in authenticationManager-config.properties located in <BUNDLE_HOME>/setup/platform_conf/initial/tenant_template_portal for not initialized platform or <BUNDLE_HOME>/setup/platform_conf/current/tenant_template_portal and <BUNDLE_HOME>/setup/platform_conf/current/tenants/<TENANT_ID>/tenant_portal/.

  2. If the logout URL of your OIDC provider supports a parameter to redirect after the logout, you can set the property oidc.logout.url.redirectQuery with the query string to use (it will be concatenated to the logout URL). The placeholder {encodedRedirectUri} will be replaced at runtime with the current Bonita URL at the time on the logout action.

If the logout flow supported by your OIDC provider is not the same as the one supported by Bonita platform, the preferred solution to handle it anyway is to intercept the requests to /logoutService and handle the logout programmatically.

Troubleshoot

To troubleshoot SSO login issues, you need to increase the log level to FINE for the packages org.bonitasoft, com.bonitasoft, and ALL for org.keycloak in order for errors to be displayed in the log files bonita-*.log (by default, they are not).

In order to do that in a Tomcat bundle, you need to edit the file <BUNDLE_HOME>/server/conf/logging.properties.

  • Make sure the following lines are not commented or add them if they are not present (the syntaxe of the first line with class\ is necessary because of the way the loggers are created in Keycloak):

    class\ org.keycloak.level = ALL
    org.keycloak.level = ALL
  • Update the existing lines (to set the level to FINE):

    org.bonitasoft.level = FINE
    com.bonitasoft.level = FINE

Common error examples

Symptom: After configuring OIDC SSO in Bonita, the Bonita login page appears and you are not redirected to the SSO login page.
Possible Solutions:

  • Check all the Bonita configuration settings are correct.

  • Make sure setup[.sh][.bat] push has been executed and the server restarted after the changes.

  • Try cleaning the cache and cookies of the web browser.

Symptom: After logging in on the OIDC provider, you are redirected to Bonita but you get a 403 error.
Problem: Either Bonita OIDC module does not manage to obtain the access tokens, or you don’t have the required rights to access the page (when trying to display a page of an application without having the required profile for example).
Solution: Check the logs:

  • If you see a message failed to turn code into token, it meens you are in the first situation. The next lines in the logs should indicate the origin of the problem. Usually, you will need to update the file keycloak-oidc.json to match the configuration of Bonita client declared on the OIDC provider. For example, you may get the following error in the logs: Unauthorized client with as error description: invalid client secret. In this case, just fix the client secret in the file keycloak-oidc.json (and push the new configuration into database using the setup tool).

  • If you don’t see any keycloak message, then it probably means the user trying to log in just does not have the required profile to see the application. Go to the profile list page and check the profile associated with the application to make sure the user has this profile.

Manage passwords

When your Bonita platform is configured to manage authentication over OIDC, the user password are managed in your OIDC Provider (IdP). However, when you create a user in Bonita Applications, specifying a password is mandatory. This password is ignored when logging in with the OIDC provider.

LDAP synchronizer and OIDC

If you are using an LDAP service and the LDAP synchronizer to manage your user data,
you can continue to do this and manage authentication over OIDC.
The LDAP synchronizer user must be registered in Bonita (no need for an OIDC account). It is recommended though to use the tenant admin account. We recommend that you use LDAP as your master source for information, synchronizing the relevant information with your Bonita platform.

By default the LDAP synchronizer sets the password of the accounts created with the same value as the username. So, even if you allow standard authentication (by setting the property oidc.auth.standard.allowed in authenticationManager-config.properties), users won’t be able to log in with the Bonita login page directly without going through the OIDC provider authentication.

Using Bonita REST API with OIDC

When Bonita web application is configured for authentication with OpenID Connect, Bonita REST API is secured through OIDC too and it is possible to call it with just an OAuth Access token. This means "statelessness" as there is no need for a sticky session between the client and Bonita REST API. This is a major advantage if you want to use the REST API of a Bonita cluster of several nodes.

Authentication

To obtain the access token, there are several options depending on your OpenID Connect provider configuration and your use case:

Resource Owner Credentials Grant

In this scenario, the client application that needs to use Bonita REST API performs a request to the token end point of the OIDC provider with the username and password of the user account to use in Bonita.
For example, using a Keyclaok server as OIDC provider, with a realm named bonita and a client Id bonitaOIDC:

  POST /auth/realms/bonita/protocol/openid-connect/token  HTTP/1.1
  Host: localhost:9090
  Content-Type: application/x-www-form-urlencoded

  grant_type:password
  password:<user IdP password>
  username:<user IdP username>
  client_id:bonitaOIDC

The token endpoint of the OIDC provider will answer with an ID and an access token. Once you obtained the Access token, you can make your REST API request in a normal way, just adding a header Authorization with value Bearer <Access token> (replace the placeholder <Access token> with the token returned by the OIDC provider and make sure to keep the whitespace after Bearer).

Authorization Code Grant

Those scenarios work the same way as when you login into Bonita Runtime except, in this case, it is the client application that uses Bonita REST API which needs to trigger the authentication process by calling the OIDC provider authorization endpoint with Bonita OIDC client as client_id. The rest of the scenario is similar to what is described in the OIDC Authorization Code Flow schema.
For example, if Bonita is configured to use Google’s OpenID Connect endpoint for authentication, then an application that wants to use Bonita REST API will need to delegate authentication to Google to obtain an authorization code for Bonita REST API.
With Authorization Code Flow, once you obtain the authorization code, you can request again the OIDC provider to get the tokens with as grant_type value authorization_code:

  POST /auth/realms/bonita/protocol/openid-connect/token  HTTP/1.1
  Host: localhost:9090
  Content-Type: application/x-www-form-urlencoded

  grant_type:authorization_code
  code:<your code from the OIDC response after user login/consent>
  client_id:<your client ID>
  client_secret:<your client secret>

The token endpoint of the OIDC provider will answer with an ID and an access token. Once you obtained the Access token, you can make your REST API request in a normal way, just adding a header Authorization with value Bearer <Access token>.

If the OIDC provider returns opaque access token (non JWT), then Bonita OIDC client module will use UserInfo OIDC endpoint to validate the token and retrieve the user claims. Make sure the property user-info-url is correct in the file keycloak-oidc.json.

CORS

If you want to call Bonita REST API from a page hosted on another domain than the one of the Bonita server, you need to enable Cross-Origin Resource Sharing (CORS) through OIDC. In the file keycloak-oidc.json, Make sure the property enable-cors is set to true and the properties cors-allowed-methods, cors-allowed-headers, cors-exposed-headers have the correct values. For a basic configuration, you can use the same values as in the configuration of the CORS filter (which is the way to handle CORS when Bonita web application is not configured for Authentication with OIDC). Also make sure to update the sameSiteCookies policy of the Tomcat server.