CAS Spring Boot Administration

CAS takes advantage of the Spring Boot Admin to manage and monitor its internal state visually. As a Spring Boot Admin client, CAS registers itself with the Spring Boot Admin server over HTTP and reports back its status and health to the server’s web interface.

Administration Server

The Spring Boot Admin web application server is not part of the CAS server and is a standalone web application which can be deployed using the CAS Initializr.

Secure Endpoints

Note that the admin server's API endpoints MUST be secured. It is also best to run both the Admin server and the registering CAS server node under HTTPS, specially if credentials are used to authenticate into endpoints.

To learn more about options, please see this guide.

CAS Server as Client

Each individual CAS server is given the ability to auto-register itself with the admin server, provided configuration is made available to instruct the CAS server how to locate and connect to the admin server.

Support is added by including the following dependency in the WAR overlay:

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<dependency>
  <groupId>org.apereo.cas</groupId>
  <artifactId>cas-server-support-bootadmin-client</artifactId>
  <version>${cas.version}</version>
</dependency>
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implementation "org.apereo.cas:cas-server-support-bootadmin-client:${project.'cas.version'}"
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dependencyManagement {
  imports {
    mavenBom "org.apereo.cas:cas-server-support-bom:${project.'cas.version'}"
  }
}

dependencies {  
  implementation "org.apereo.cas:cas-server-support-bootadmin-client"
}

Note that CAS server’s actuator endpoints are by default secured. In order to allow secure communication between the CAS server and the Spring Boot Admin server, please see guide.

Configuration

The following settings and properties are available from the CAS configuration catalog:

The configuration settings listed below are tagged as Required in the CAS configuration metadata. This flag indicates that the presence of the setting may be needed to activate or affect the behavior of the CAS feature and generally should be reviewed, possibly owned and adjusted. If the setting is assigned a default value, you do not need to strictly put the setting in your copy of the configuration, but should review it nonetheless to make sure it matches your deployment expectations.

The configuration settings listed below are tagged as Optional in the CAS configuration metadata. This flag indicates that the presence of the setting is not immediately necessary in the end-user CAS configuration, because a default value is assigned or the activation of the feature is not conditionally controlled by the setting value. You should only include this field in your configuration if you need to modify the default value.

The configuration settings listed below are tagged as Third Party in the CAS configuration metadata. This flag indicates that the configuration setting is not controlled, owned or managed by the CAS ecosystem, and affects functionality that is offered by a third-party library, such as Spring Boot or Spring Cloud to CAS. For additional info, you might have to visit the third-party source to find more details.

  • spring.boot.admin.client.api-path=instances
  • The admin rest-apis path.

    de.codecentric.boot.admin.client.config.ClientProperties.

  • spring.boot.admin.client.auto-deregistration=
  • Enable automatic deregistration on shutdown If not set it defaults to true if a active CloudPlatform is present;

    de.codecentric.boot.admin.client.config.ClientProperties.

  • spring.boot.admin.client.auto-registration=true
  • Enable automatic registration when the application is ready.

    de.codecentric.boot.admin.client.config.ClientProperties.

  • spring.boot.admin.client.connect-timeout=5000ms
  • Connect timeout for the registration.

    de.codecentric.boot.admin.client.config.ClientProperties.

  • spring.boot.admin.client.enabled=true
  • Enable Spring Admin Client.

    de.codecentric.boot.admin.client.config.ClientProperties.

  • spring.boot.admin.client.instance.health-url=
  • Client-health-URL to register with. Inferred at runtime, can be overridden in case the reachable URL is different (e.g. Docker). Must be unique all services registry.

    de.codecentric.boot.admin.client.config.InstanceProperties.

  • spring.boot.admin.client.instance.management-base-url=
  • Base url for computing the management-url to register with. The path is inferred at runtime, and appended to the base url.

    de.codecentric.boot.admin.client.config.InstanceProperties.

  • spring.boot.admin.client.instance.management-url=
  • Management-url to register with. Inferred at runtime, can be overridden in case the reachable URL is different (e.g. Docker).

    de.codecentric.boot.admin.client.config.InstanceProperties.

  • spring.boot.admin.client.instance.metadata=
  • Metadata that should be associated with this application

    de.codecentric.boot.admin.client.config.InstanceProperties.

  • spring.boot.admin.client.instance.name=spring-boot-application
  • Name to register with. Defaults to ${spring.application.name</code>

    de.codecentric.boot.admin.client.config.InstanceProperties.

  • spring.boot.admin.client.instance.prefer-ip=false
  • Should the registered urls be built with server.address or with hostname. Deprecation: Use serviceHostType instead.

    de.codecentric.boot.admin.client.config.InstanceProperties.

    Deprecation status is WARNING without a replacement setting.

  • spring.boot.admin.client.instance.service-base-url=
  • Base url for computing the service-url to register with. The path is inferred at runtime, and appended to the base url.

    de.codecentric.boot.admin.client.config.InstanceProperties.

  • spring.boot.admin.client.instance.service-host-type=
  • Should the registered urls be built with server.address or with hostname.

    de.codecentric.boot.admin.client.config.InstanceProperties.

  • spring.boot.admin.client.instance.service-path=
  • Path for computing the service-url to register with. If not specified, defaults to "/"

    de.codecentric.boot.admin.client.config.InstanceProperties.

  • spring.boot.admin.client.instance.service-url=
  • Client-service-URL register with. Inferred at runtime, can be overridden in case the reachable URL is different (e.g. Docker).

    de.codecentric.boot.admin.client.config.InstanceProperties.

  • spring.boot.admin.client.password=
  • Password for basic authentication on admin server

    de.codecentric.boot.admin.client.config.ClientProperties.

  • spring.boot.admin.client.period=10000ms
  • Time interval the registration is repeated

    de.codecentric.boot.admin.client.config.ClientProperties.

  • spring.boot.admin.client.read-timeout=5000ms
  • Read timeout (in ms) for the registration.

    de.codecentric.boot.admin.client.config.ClientProperties.

  • spring.boot.admin.client.register-once=true
  • Enable registration against one or all admin servers

    de.codecentric.boot.admin.client.config.ClientProperties.

  • spring.boot.admin.client.url=
  • The admin server urls to register at

    de.codecentric.boot.admin.client.config.ClientProperties.

  • spring.boot.admin.client.username=
  • Username for basic authentication on admin server

    de.codecentric.boot.admin.client.config.ClientProperties.

    If you need to design your own password encoding scheme where the type is specified as a fully qualified Java class name, the structure of the class would be similar to the following:

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    package org.example.cas;
    
    import org.springframework.security.crypto.codec.*;
    import org.springframework.security.crypto.password.*;
    
    public class MyEncoder extends AbstractPasswordEncoder {
        @Override
        protected byte[] encode(CharSequence rawPassword, byte[] salt) {
            return ...
        }
    }
    

    If you need to design your own password encoding scheme where the type is specified as a path to a Groovy script, the structure of the script would be similar to the following:

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    import java.util.*
    
    byte[] run(final Object... args) {
        def rawPassword = args[0]
        def generatedSalt = args[1]
        def logger = args[2]
        def casApplicationContext = args[3]
    
        logger.debug("Encoding password...")
        return ...
    }
    
    Boolean matches(final Object... args) {
        def rawPassword = args[0]
        def encodedPassword = args[1]
        def logger = args[2]
        def casApplicationContext = args[3]
    
       logger.debug("Does match or not ?");
       return ...
    

    Password Policy Strategies

    If the password policy strategy is to be handed off to a Groovy script, the outline of the script may be as follows:

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    import java.util.*
    import org.ldaptive.auth.*
    import org.apereo.cas.*
    import org.apereo.cas.authentication.*
    import org.apereo.cas.authentication.support.*
    
    List<MessageDescriptor> run(final Object... args) {
        def response = args[0]
        def configuration = args[1];
        def logger = args[2]
        def applicationContext = args[3]
    
        logger.info("Handling password policy [{}] via ${configuration.getAccountStateHandler()}", response)
    
        def accountStateHandler = configuration.getAccountStateHandler()
        return accountStateHandler.handle(response, configuration)
    }
    

    The parameters passed are as follows:

    Parameter Description
    response The LDAP authentication response of type org.ldaptive.auth.AuthenticationResponse
    configuration The LDAP password policy configuration carrying the account state handler defined.
    logger The object responsible for issuing log messages such as logger.info(...).

    Authentication handlers that generally deal with username-password credentials can be configured to transform the user id prior to executing the authentication sequence. Each authentication strategy in CAS provides settings to properly transform the principal. Refer to the relevant settings for the authentication strategy at hand to learn more.

    Authentication handlers as part of principal transformation may also be provided a path to a Groovy script to transform the provided username. The outline of the script may take on the following form:

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    String run(final Object... args) {
        def providedUsername = args[0]
        def logger = args[1]
        return providedUsername.concat("SomethingElse")
    }
    

    Configuration Metadata

    The collection of configuration properties listed in this section are automatically generated from the CAS source and components that contain the actual field definitions, types, descriptions, modules, etc. This metadata may not always be 100% accurate, or could be lacking details and sufficient explanations.

    Be Selective

    This section is meant as a guide only. Do NOT copy/paste the entire collection of settings into your CAS configuration; rather pick only the properties that you need. Do NOT enable settings unless you are certain of their purpose and do NOT copy settings into your configuration only to keep them as reference. All these ideas lead to upgrade headaches, maintenance nightmares and premature aging.

    YAGNI

    Note that for nearly ALL use cases, declaring and configuring properties listed here is sufficient. You should NOT have to explicitly massage a CAS XML/Java/etc configuration file to design an authentication handler, create attribute release policies, etc. CAS at runtime will auto-configure all required changes for you. If you are unsure about the meaning of a given CAS setting, do NOT turn it on without hesitation. Review the codebase or better yet, ask questions to clarify the intended behavior.

    Naming Convention

    Property names can be specified in very relaxed terms. For instance cas.someProperty, cas.some-property, cas.some_property are all valid names. While all forms are accepted by CAS, there are certain components (in CAS and other frameworks used) whose activation at runtime is conditional on a property value, where this property is required to have been specified in CAS configuration using kebab case. This is both true for properties that are owned by CAS as well as those that might be presented to the system via an external library or framework such as Spring Boot, etc.

    When possible, properties should be stored in lower-case kebab format, such as cas.property-name=value. The only possible exception to this rule is when naming actuator endpoints; The name of the actuator endpoints (i.e. ssoSessions) MUST remain in camelCase mode.

    Settings and properties that are controlled by the CAS platform directly always begin with the prefix cas. All other settings are controlled and provided to CAS via other underlying frameworks and may have their own schemas and syntax. BE CAREFUL with the distinction. Unrecognized properties are rejected by CAS and/or frameworks upon which CAS depends. This means if you somehow misspell a property definition or fail to adhere to the dot-notation syntax and such, your setting is entirely refused by CAS and likely the feature it controls will never be activated in the way you intend.

    Validation

    Configuration properties are automatically validated on CAS startup to report issues with configuration binding, specially if defined CAS settings cannot be recognized or validated by the configuration schema. The validation process is on by default and can be skipped on startup using a special system property SKIP_CONFIG_VALIDATION that should be set to true. Additional validation processes are also handled via Configuration Metadata and property migrations applied automatically on startup by Spring Boot and family.

    Indexed Settings

    CAS settings able to accept multiple values are typically documented with an index, such as cas.some.setting[0]=value. The index [0] is meant to be incremented by the adopter to allow for distinct multiple configuration blocks.