CosmosDb Service Registry

Stores registered service data in an Azure CosmosDb instance.

Support is enabled by adding the following module into the overlay:

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

dependencies {  
  implementation "org.apereo.cas:cas-server-support-cosmosdb-service-registry"
}

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 is not strictly necessary in the end-user CAS configuration, because a default value may be assigned or the feature in question may not be immediately intended for use. You may want to own the setting and update it assigned value, assuming the intended feature controlled by the setting is utilized.

  • cas.service-registry.cosmos-db.collection=CasCosmosDbServiceRegistry
  • Collection to store CAS service definitions.

  • cas.service-registry.cosmos-db.database=
  • Database name.

  • cas.service-registry.cosmos-db.key=
  • Document Db master key.

  • cas.service-registry.cosmos-db.uri=
  • Document Db host address (i.e. https://localhost:8081).

    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.

  • cas.service-registry.cosmos-db.allow-telemetry=true
  • Whether telemetry should be enabled by default.

  • cas.service-registry.cosmos-db.consistency-level=Session
  • Document Db consistency level. Azure Cosmos DB is designed from the ground up with global distribution in mind for every data model. It is designed to offer predictable low latency guarantees, a 99.99% availability SLA, and multiple well-defined relaxed consistency models. Currently, Azure Cosmos DB provides five consistency levels: strong, bounded-staleness, session, consistent prefix, and eventual. Besides strong and eventual consistency models commonly offered by distributed databases, Azure Cosmos DB offers three more carefully codified and operationalized consistency models, and has validated their usefulness against real world use cases. These are the bounded staleness, session, and consistent prefix consistency levels. Collectively these five consistency levels enable you to make well-reasoned trade-offs between consistency, availability, and latency. Accepted values are:

    • Strong: Linearizability
    • Session: Consistent Prefix. Monotonic reads, monotonic writes, read-your-writes, write-follows-reads
    • Eventual: Out of order reads
    • BoundedStaleness: Consistent Prefix. Reads lag behind writes by k prefixes or t interval
    • ConsistentPrefix: Updates returned are some prefix of all the updates, with no gaps

  • cas.service-registry.cosmos-db.drop-collection=false
  • Whether collections should be dropped on startup and re-created.

  • cas.service-registry.cosmos-db.indexing-mode=None
  • Specifies the supported indexing modes in the Azure Cosmos DB database service. Accepted values are:

    • Consistent: Index is updated synchronously with a create or update operation. With consistent indexing, query behavior is the same as the default consistency level for the collection. The index is always kept up to date with the data.
    • Lazy: Index is updated asynchronously with respect to a create or update operation. With lazy indexing, queries are eventually consistent. The index is updated when the collection is idle.
    • None: No index is provided. Setting IndexingMode to "None" drops the index. Use this if you don't want to maintain the index for a document collection, to save the storage cost or improve the write throughput. Your queries will degenerate to scans of the entire collection.

  • cas.service-registry.cosmos-db.throughput=10000
  • Database throughput usually between 400 or 100,000.


    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. Over time and with community contributions, the accuracy and volume of the documentation should improve over time.

    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 below 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.S ettings 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.

    Time Unit of Measure

    All CAS settings that deal with time units, unless noted otherwise, should support the duration syntax for full clarity on unit of measure: PT20S, PT15M, PT10H, PT6D, P2DT3H4M.

    Troubleshooting

    To enable additional logging, configure the log4j configuration file to add the following levels:

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    ...
    <Logger name="com.microsoft.azure" level="debug" additivity="false">
        <AppenderRef ref="console"/>
        <AppenderRef ref="file"/>
    </Logger>
    ...
    

    Auto Initialization

    Upon startup and configuration permitting, the registry is able to auto initialize itself from default JSON service definitions available to CAS. See this guide for more info.