Registering Strategies

The Three Fields

Strategies are registered via the callcoreio__ExtensibilityStrategy__mdt custom metadata type. Each record maps a strategy type and discriminator to an Apex class name.

Field	API Name	Required	Description
Strategy Type	`callcoreio__StrategyType__c`	Yes	Which extensibility point this record configures. Restricted picklist.
Discriminator	`callcoreio__Discriminator__c`	No	Narrows which scenario this record applies to. See values per strategy below.
Apex Class Name	`callcoreio__ApexClassName__c`	Yes	The unqualified name of your Apex class implementing the strategy interface.

Strategy Type Values

Picklist Value	Strategy
`BuildCommunicationScopeForRecord`	Build Communication Scope
`GatherPhoneNumbersFromRecords`	Gather Phone Numbers
`GetUserForCallHandler`	Get User for Call Handler
`RestrictCallHandlers`	Restrict Call Handlers
`RestrictSources`	Restrict Sources

Discriminator Values

Strategy	Discriminator to use
`BuildCommunicationScopeForRecord`	`RecordType:<SObjectApiName>` for object-specific (e.g., `RecordType:Project__c`); `default` for a catch-all
`GatherPhoneNumbersFromRecords`	`RecordType:<SObjectApiName>` for object-specific (e.g., `RecordType:Supplier__c`); `default` for a catch-all
`GetUserForCallHandler`	`default`
`RestrictCallHandlers`	`default`
`RestrictSources`	`default`

The discriminator field is case-insensitive. RecordType:Contact and recordtype:contact resolve to the same record.

Class Name Resolution

Enter your class name without a namespace prefix. Incorrect class names, or class names that exist but do not implement the required interface, produce a CallCoreExtensibilityMisconfigurationException at runtime. Enable CallCore_DebugMode when testing to have this exception surfaced rather than swallowed.

Deploying via Metadata

To deploy strategy registrations as part of your org's metadata, add records to the customMetadata/ folder in your Salesforce project. File names follow the convention:

customMetadata/callcoreio__ExtensibilityStrategy.<DeveloperName>.md-meta.xml

The <DeveloperName> is a unique identifier for the record within your org.

Example: Single Global Strategy

Registering a custom GetUserForCallHandler implementation:

<?xml version="1.0" encoding="UTF-8"?>
<CustomMetadata xmlns="http://soap.sforce.com/2006/04/metadata"
                xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <label>Get User by Extension</label>
    <protected>false</protected>
    <values>
        <field>callcoreio__StrategyType__c</field>
        <value xsi:type="xsd:string">GetUserForCallHandler</value>
    </values>
    <values>
        <field>callcoreio__Discriminator__c</field>
        <value xsi:type="xsd:string">default</value>
    </values>
    <values>
        <field>callcoreio__ApexClassName__c</field>
        <value xsi:type="xsd:string">GetUserForCallHandlerByExtension</value>
    </values>
</CustomMetadata>

File: customMetadata/callcoreio__ExtensibilityStrategy.Get_User_By_Extension.md-meta.xml

Example: Object-Specific Scope Strategy

Registering a BuildCommunicationScopeForRecord implementation for Project__c:

<?xml version="1.0" encoding="UTF-8"?>
<CustomMetadata xmlns="http://soap.sforce.com/2006/04/metadata"
                xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <label>Build Project Communications Scope</label>
    <protected>false</protected>
    <values>
        <field>callcoreio__StrategyType__c</field>
        <value xsi:type="xsd:string">BuildCommunicationScopeForRecord</value>
    </values>
    <values>
        <field>callcoreio__Discriminator__c</field>
        <value xsi:type="xsd:string">RecordType:Project__c</value>
    </values>
    <values>
        <field>callcoreio__ApexClassName__c</field>
        <value xsi:type="xsd:string">BuildProjectCommsScope</value>
    </values>
</CustomMetadata>

File: customMetadata/callcoreio__ExtensibilityStrategy.Build_Project_Comms_Scope.md-meta.xml

Using Setup UI

Custom metadata records can also be created manually through Setup:

Go to Setup → Custom Metadata Types.
Find CallCore Extensibility Strategy and click Manage Records.
Click New.
Fill in the Label, Strategy Type, Discriminator, and Apex Class Name.
Click Save.

Changes take effect immediately without a deploy.

One Record Per Strategy + Discriminator

Only one metadata record is permitted per StrategyType__c + Discriminator__c combination. If more than one record with the same combination exists, the framework throws CallCoreExtensibilityMisconfigurationException at runtime. Enable debug mode to surface this error.

Interaction with Packaged Defaults

A registered metadata record always takes precedence over the packaged default for the same discriminator. To revert to the packaged default, delete the metadata record — you do not need to deploy a new class.

If you register a default discriminator and also a specific RecordType:Contact discriminator, the RecordType:Contact record wins for Contact pages. The default record applies to everything else (unless overridden by another object-specific record).