APEREO CASDocumentation

Enterprise Authentication for All Earthlings and Beyond

Identity, Single Sign-On and Access Management
View on GitHub

Spring Cloud Configuration Server - Spring Cloud Apache ZooKeeper

Spring Cloud Configuration Server is able to use Apache ZooKeeper to locate properties and settings.

Support is provided via the following dependency in the WAR overlay:



1
2
3
4
5



<dependency>
    <groupId>org.apereo.cas</groupId>
    <artifactId>cas-server-support-configuration-cloud-zookeeper</artifactId>
    <version>${cas.version}</version>
</dependency>





1



implementation "org.apereo.cas:cas-server-support-configuration-cloud-zookeeper:${project.'cas.version'}"





1
2
3
4
5
6
7
8
9



dependencyManagement {
    imports {
        mavenBom "org.apereo.cas:cas-server-support-bom:${project.'cas.version'}"
    }
}

dependencies {
    implementation "org.apereo.cas:cas-server-support-configuration-cloud-zookeeper"
}





1
2
3
4
5
6
7
8
9
10



dependencies {
    /*
        The following platform references are included automatically and are listed for reference only.

        implementation enforcedPlatform("org.apereo.cas:cas-server-support-bom:${project.'cas.version'}")
        implementation platform(org.springframework.boot.gradle.plugin.SpringBootPlugin.BOM_COORDINATES)
        
    */
    implementation "org.apereo.cas:cas-server-support-configuration-cloud-zookeeper"
}
:information_source: Usage

The configuration modules provided here may also be used verbatim inside a CAS server overlay and do not exclusively belong to a Spring Cloud Configuration server. While this module is primarily useful when inside the Spring Cloud Configuration server, it nonetheless may also be used inside a CAS server overlay directly to fetch settings from a source.

You will need to map CAS settings to ZooKeeper’s nodes that contain values. The parent node for all settings should match the configuration root value provided to CAS. Under the root, you could have folders such as cas, cas,dev, cas,local, etc where dev and local are Spring profiles.

To create nodes and values in Apache ZooKeeper, try the following commands as a sample:



1
2
3
4
5



zookeeper-client -server zookeeper1:2181
create /cas cas
create /cas/config cas
create /cas/config/cas cas
create /cas/config/cas/settingName casuser::Test

Creating nodes and directories in Apache ZooKeeper may require providing a value. The above sample commands show that the value cas is provided when creating directories. Always check with the official Apache ZooKeeper guides. You may not need to do that step.

Finally in your CAS properties, the new settingName setting can be used as a reference.



1



# cas.something.something=${settingName}

…where ${settingName} gets the value of the contents of the Apache ZooKeeper node cas/config/cas/settingName.

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

spring.cloud.zookeeper.base-sleep-time-msInitial amount of time to wait between retries.
50
Third party

Initial amount of time to wait between retries.

Type
Integer
Default
50
Defined by
ZookeeperProperties
spring.cloud.zookeeper.block-until-connected-unitThe unit of time related to blocking on connection to Zookeeper.
seconds
Third party

The unit of time related to blocking on connection to Zookeeper.

Type
TimeUnit
Default
seconds
Defined by
ZookeeperProperties
spring.cloud.zookeeper.block-until-connected-waitWait time to block on connection to Zookeeper.
10
Third party

Wait time to block on connection to Zookeeper.

Type
Integer
Default
10
Defined by
ZookeeperProperties
spring.cloud.zookeeper.config.default-contextThe name of the default context.
application
Third party

The name of the default context.

Type
String
Default
application
Defined by
ZookeeperConfigProperties
spring.cloud.zookeeper.config.enabled
true
Third party
Type
Boolean
Default
true
Defined by
ZookeeperConfigProperties
spring.cloud.zookeeper.config.fail-fastThrow exceptions during config lookup if true, otherwise, log warnings.
true
Third party

Throw exceptions during config lookup if true, otherwise, log warnings.

Type
Boolean
Default
true
Defined by
ZookeeperConfigProperties
spring.cloud.zookeeper.config.nameAlternative to spring.application.name to use in looking up values in zookeeper.
no default
Third party

Alternative to spring.application.name to use in looking up values in zookeeper.

Type
String
Default
none
Defined by
ZookeeperConfigProperties
spring.cloud.zookeeper.config.profile-separatorSeparator for profile appended to the application name.
,
Third party

Separator for profile appended to the application name.

Type
String
Default
,
Defined by
ZookeeperConfigProperties
spring.cloud.zookeeper.config.rootRoot folder where the configuration for Zookeeper is kept.
config
Third party

Root folder where the configuration for Zookeeper is kept.

Type
String
Default
config
Defined by
ZookeeperConfigProperties
spring.cloud.zookeeper.connect-stringConnection string to the Zookeeper cluster.
localhost:2181
Third party

Connection string to the Zookeeper cluster.

Type
String
Default
localhost:2181
Defined by
ZookeeperProperties
spring.cloud.zookeeper.connection-timeoutThe configured connection timeout in milliseconds.
no default
Third party

The configured connection timeout in milliseconds.

Type
Duration
Default
none
Defined by
ZookeeperProperties
spring.cloud.zookeeper.dependenciesMapping of alias to ZookeeperDependency.
no default
Third party

Mapping of alias to ZookeeperDependency. From LoadBalancer perspective the alias is actually serviceID since SC LoadBalancer can't accept nested structures in serviceID.

Type
Map<String,ZookeeperDependency>
Default
none
Defined by
ZookeeperDependencies
spring.cloud.zookeeper.dependency-configurations
no default
Third party
Type
Collection<ZookeeperDependency>
Default
none
Defined by
ZookeeperDependencies
spring.cloud.zookeeper.dependency-names
no default
Third party
Type
Collection<String>
Default
none
Defined by
ZookeeperDependencies
spring.cloud.zookeeper.discovery.enabled
true
Third party
Type
Boolean
Default
true
Defined by
ZookeeperDiscoveryProperties
spring.cloud.zookeeper.discovery.initial-statusThe initial status of this instance (defaults to StatusConstants#STATUS_UP ).
no default
Third party

The initial status of this instance (defaults to StatusConstants#STATUS_UP).

Type
String
Default
none
Defined by
ZookeeperDiscoveryProperties
spring.cloud.zookeeper.discovery.instance-hostPredefined host with which a service can register itself in Zookeeper.
no default
Third party

Predefined host with which a service can register itself in Zookeeper. Corresponds to the {code address} from the URI spec.

Type
String
Default
none
Defined by
ZookeeperDiscoveryProperties
spring.cloud.zookeeper.discovery.instance-idId used to register with zookeeper.
no default
Third party

Id used to register with zookeeper. Defaults to a random UUID.

Type
String
Default
none
Defined by
ZookeeperDiscoveryProperties
spring.cloud.zookeeper.discovery.instance-portPort to register the service under (defaults to listening port).
no default
Third party

Port to register the service under (defaults to listening port).

Type
Integer
Default
none
Defined by
ZookeeperDiscoveryProperties
spring.cloud.zookeeper.discovery.instance-ssl-portSsl port of the registered service.
no default
Third party

Ssl port of the registered service.

Type
Integer
Default
none
Defined by
ZookeeperDiscoveryProperties
spring.cloud.zookeeper.discovery.metadataGets the metadata name/value pairs associated with this instance.
no default
Third party

Gets the metadata name/value pairs associated with this instance. This information is sent to zookeeper and can be used by other instances.

Type
Map<String,String>
Default
none
Defined by
ZookeeperDiscoveryProperties
spring.cloud.zookeeper.discovery.orderOrder of the discovery client used by `CompositeDiscoveryClient` for sorting available clients.
0
Third party

Order of the discovery client used by `CompositeDiscoveryClient` for sorting available clients.

Type
Integer
Default
0
Defined by
ZookeeperDiscoveryProperties
spring.cloud.zookeeper.discovery.registerRegister as a service in zookeeper.
true
Third party

Register as a service in zookeeper.

Type
Boolean
Default
true
Defined by
ZookeeperDiscoveryProperties
spring.cloud.zookeeper.discovery.rootRoot Zookeeper folder in which all instances are registered.
/services
Third party

Root Zookeeper folder in which all instances are registered.

Type
String
Default
/services
Defined by
ZookeeperDiscoveryProperties
spring.cloud.zookeeper.discovery.uri-specThe URI specification to resolve during service registration in Zookeeper.
{scheme}://{address}:{port}
Third party

The URI specification to resolve during service registration in Zookeeper.

Type
String
Default
{scheme}://{address}:{port}
Defined by
ZookeeperDiscoveryProperties
spring.cloud.zookeeper.enabledIs Zookeeper enabled.
true
Third party

Is Zookeeper enabled.

Type
Boolean
Default
true
Defined by
ZookeeperProperties
spring.cloud.zookeeper.max-retriesMax number of times to retry.
10
Third party

Max number of times to retry.

Type
Integer
Default
10
Defined by
ZookeeperProperties
spring.cloud.zookeeper.max-sleep-msMax time in ms to sleep on each retry.
500
Third party

Max time in ms to sleep on each retry.

Type
Integer
Default
500
Defined by
ZookeeperProperties
spring.cloud.zookeeper.prefixCommon prefix that will be applied to all Zookeeper dependencies' paths.
no default
Third party

Common prefix that will be applied to all Zookeeper dependencies' paths.

Type
String
Default
none
Defined by
ZookeeperDependencies
spring.cloud.zookeeper.session-timeoutThe configured/negotiated session timeout in milliseconds.
no default
Third party

The configured/negotiated session timeout in milliseconds. Please refer to Curator's Tech Note 14 to understand how Curator implements connection sessions. @see Curator's Tech Note 14

Type
Duration
Default
none
Defined by
ZookeeperProperties

Required settings may be needed to activate or affect the feature; review them even when they have a default. Optional settings only need to be set to change a default or to turn on the behavior they control. Third party settings belong to libraries such as Spring Boot that CAS builds on; their own documentation may have more detail.

Notes on configuration

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.

:information_source: Note

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, especially if defined CAS settings cannot be recognized or validated by the configuration schema. 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.

Actuator Endpoints

The following endpoints are provided by CAS:

health
Third-party endpoint2 operationsExposed by default
1

Turn the endpoint on and expose it over the web. One entry covers every operation. By default only info, health and status are exposed.



1
2



management.endpoint.health.access=UNRESTRICTED
management.endpoints.web.exposure.include=health

Endpoints may be mapped to other paths. For example, to serve health at healthcheck:



1



management.endpoints.web.path-mapping.health=healthcheck