Improvements to the trigger handler

Ability to disable trigger action in meta-data, and adds a stateful option

Signed-off-by: WimVelzeboer <wimvelzeboer@protonmail.com>

sfdx-source/apex-extensions/main/triggerHandler/classes/fflib_TriggerActionConfig.cls

@@ -66,7 +66,6 @@ public virtual inherited sharing class fflib_TriggerActionConfig
 		else if (triggerAction.ExecutionContext__c == 'Dedicated Queued') this.dedicatedQueued = true;
 
 		// Get SObjectType
-		System.debug('triggerAction: '+triggerAction);
 		String ObjectTypeApiName =
 				String.isNotBlank(triggerAction.ObjectType__c)
 					? triggerAction.ObjectType__r?.QualifiedApiName?.toLowerCase().trim()
@@ -74,6 +73,14 @@ public virtual inherited sharing class fflib_TriggerActionConfig
 		this.sObjectType = Schema.describeSObjects(new List<String> {ObjectTypeApiName}).get(0).getSObjectType();
 	}
 
+	/**
+	 * @return Returns the Implementation Type of the Trigger Action
+	 */
+	public Type getImplementationType()
+	{
+		return this.implementationType;
+	}
+
 	/**
 	 * @return Returns the sequence number of the trigger action
 	 */
@@ -90,6 +97,14 @@ public virtual inherited sharing class fflib_TriggerActionConfig
 		return (this.dedicatedQueued != null && this.dedicatedQueued);
 	}
 
+	/**
+	 * @return Returns TRUE if the trigger action needs to be kept in memory and reused by the next TriggerHandler run
+	 */
+	public Boolean isStateful()
+	{
+		return this.stateful;
+	}
+
 	/**
 	 * @return Returns TRUE if the trigger action can be executed in an Queueable context
 	 */
@@ -107,4 +122,15 @@ public virtual inherited sharing class fflib_TriggerActionConfig
 	{
 		return (fflib_ITriggerAction) implementationType.newInstance();
 	}
+
+	public Boolean hasTriggerContext(TriggerOperation triggerOperation)
+	{
+		return (triggerOperation == System.TriggerOperation.BEFORE_INSERT && beforeInsert)
+				|| (triggerOperation == System.TriggerOperation.BEFORE_UPDATE && beforeUpdate)
+				|| (triggerOperation == System.TriggerOperation.BEFORE_DELETE && beforeDelete)
+				|| (triggerOperation == System.TriggerOperation.AFTER_DELETE && afterDelete)
+				|| (triggerOperation == System.TriggerOperation.AFTER_INSERT && afterInsert)
+				|| (triggerOperation == System.TriggerOperation.AFTER_UNDELETE && afterUndelete)
+				|| (triggerOperation == System.TriggerOperation.AFTER_UPDATE && afterUpdate);
+	}
 }

sfdx-source/apex-extensions/main/triggerHandler/classes/fflib_TriggerActionConfigSelector.cls

@@ -65,12 +65,12 @@ public virtual inherited sharing class fflib_TriggerActionConfigSelector
 	/**
 	 * @return Query all fflib_TriggerAction__mdt records
 	 */
-	public virtual List<fflib_TriggerAction__mdt> selectAll()
+	public virtual List<fflib_TriggerAction__mdt> selectAllActive()
 	{
 		return (List <fflib_TriggerAction__mdt>) Database.query(
 
 				String.format(
-						'SELECT {0} FROM {1}',
+						'SELECT {0} FROM {1} WHERE IsActive__c=TRUE',
 						new List<String>
 						{
 								getFieldListString() + ', ObjectType__r.QualifiedApiName',

sfdx-source/apex-extensions/main/triggerHandler/classes/fflib_TriggerHandler.cls

@@ -48,6 +48,12 @@ public virtual with sharing class fflib_TriggerHandler
 
 	protected fflib_ITriggerContext triggerContext;
 
+	/**
+	 * Retain instance of Trigger Action classes implementing stateful
+	 */
+	@TestVisible
+	private static Map<Type, fflib_ITriggerAction> triggerActionStateByClass;
+
 	/**
 	 * Provides access to the trigger action configurations and allowing it to be mocked in unit-tests
 	 */
@@ -101,7 +107,9 @@ public virtual with sharing class fflib_TriggerHandler
 		fflib_UnitOfWork unitOfWork = new fflib_UnitOfWork();
 		for (fflib_ITriggerActionConfig triggerActionConfig : configs)
 		{
-			fflib_ITriggerAction triggerAction = triggerActionConfig.newInstance();
+			if (isValidExecutionContext(ctx, triggerActionConfig) == false) continue;
+
+			fflib_ITriggerAction triggerAction = getTriggerActionInstance(triggerActionConfig);
 
 			triggerAction.setContext(ctx);
 			triggerAction.setSequence(triggerActionConfig.getSequence());
@@ -117,12 +125,29 @@ public virtual with sharing class fflib_TriggerHandler
 		unitOfWork.doWork();
 	}
 
+	private Boolean isValidExecutionContext(fflib_ITriggerContext ctx, fflib_ITriggerActionConfig config)
+	{
+		return config.hasTriggerContext(ctx.getTriggerOperation());
+	}
+
+	private fflib_ITriggerAction getTriggerActionInstance(fflib_ITriggerActionConfig triggerActionConfig)
+	{
+		if (triggerActionConfig.isStateful()
+				&& triggerActionStateByClass != null
+				&& triggerActionStateByClass.containsKey(triggerActionConfig.getImplementationType()))
+		{
+			return triggerActionStateByClass.get(triggerActionConfig.getImplementationType());
+		}
+
+		return triggerActionConfig.newInstance();
+	}
+
 	@TestVisible
 	protected void loadConfiguration()
 	{
 		if (configs.isEmpty() == false) return;
 
-		for (fflib_TriggerAction__mdt action : new fflib_TriggerActionConfigSelector().selectAll())
+		for (fflib_TriggerAction__mdt action : new fflib_TriggerActionConfigSelector().selectAllActive())
 		{
 			configs.add( new fflib_TriggerActionConfig(action));
 		}

sfdx-source/apex-extensions/main/triggerHandler/classes/interfaces/fflib_ITriggerActionConfig.cls

@@ -29,16 +29,33 @@
  */
 public interface fflib_ITriggerActionConfig
 {
+	/**
+	 * @return Returns the Implementation Type of the Trigger Action
+	 */
+	System.Type getImplementationType();
+
 	/**
 	 * @return Returns the sequence number of the trigger action
 	 */
 	Integer getSequence();
 
+	/**
+	 * @param triggerOperation The Trigger operation to validate the configuration against.
+	 *
+	 * @return Returns TRUE is the given operation type matches the one of the configuration
+	 */
+	Boolean hasTriggerContext(TriggerOperation triggerOperation);
+
 	/**
 	 * @return Returns TRUE if the trigger action should be executed in a dedicated Queueable context
 	 */
 	Boolean isDedicatedQueued();
 
+	/**
+	 * @return Returns TRUE if the trigger action needs to be kept in memory and reused by the next TriggerHandler run
+	 */
+	Boolean isStateful();
+
 	/**
 	 * @return Returns TRUE if the trigger action can be executed in an Queueable context
 	 */
@@ -50,4 +67,6 @@ public interface fflib_ITriggerActionConfig
 	 * @return Instance of the Trigger Action class
 	 */
 	fflib_ITriggerAction newInstance();
+
+
 }

sfdx-source/apex-extensions/main/triggerHandler/classes/interfaces/fflib_ITriggerActionConfigSelector.cls

@@ -32,5 +32,5 @@ public interface fflib_ITriggerActionConfigSelector
 	/**
 	 * @return Query all fflib_TriggerAction__mdt records
 	 */
-	List<fflib_TriggerAction__mdt> selectAll();
+	List<fflib_TriggerAction__mdt> selectAllActive();
 }

sfdx-source/apex-extensions/main/triggerHandler/layouts/fflib_TriggerAction__mdt-Trigger Action Layout.layout-meta.xml

@@ -24,6 +24,10 @@
                 <behavior>Required</behavior>
                 <field>NamespacePrefix</field>
             </layoutItems>
+            <layoutItems>
+                <behavior>Edit</behavior>
+                <field>IsActive__c</field>
+            </layoutItems>
         </layoutColumns>
         <style>TwoColumnsTopToBottom</style>
     </layoutSections>

sfdx-source/apex-extensions/main/triggerHandler/objects/fflib_TriggerAction__mdt/fields/IsActive__c.field-meta.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<CustomField xmlns="http://soap.sforce.com/2006/04/metadata">
+    <fullName>IsActive__c</fullName>
+    <defaultValue>true</defaultValue>
+    <externalId>false</externalId>
+    <fieldManageability>DeveloperControlled</fieldManageability>
+    <label>Is Active</label>
+    <type>Checkbox</type>
+</CustomField>

sfdx-source/apex-extensions/tests/classes/triggerHandler/fflib_TriggerHandlerTest.cls

@@ -252,7 +252,49 @@ private class fflib_TriggerHandlerTest
 		System.assert(ctx.isUpdate());
 	}
 
+	@IsTest
+	private static void itShouldUseTheStatefulTriggerActionClass()
+	{
+		fflib_LogEntry__c record = new fflib_LogEntry__c(LogLevel__c = 'INFO', Message__c = 'Unit Test');
+		List<fflib_LogEntry__c> records = new List<fflib_LogEntry__c> {record};
 
+		fflib_ApexMocks mocks = new fflib_ApexMocks();
+		fflib_ITriggerAction triggerActionMock = (fflib_ITriggerAction) mocks.mock(fflib_ITriggerAction.class);
+
+		mocks.startStubbing();
+		mocks.when(triggerActionMock.isQueueable()).thenReturn(false);
+		mocks.when(triggerActionMock.isNotQueueable()).thenReturn(true);
+		mocks.stopStubbing();
+
+		fflib_TriggerHandler.triggerActionStateByClass =
+				new Map<Type, fflib_ITriggerAction>{ MyTriggerAction.class => triggerActionMock };
+
+		fflib_TriggerAction__mdt triggerAction = new fflib_TriggerAction__mdt(
+				ObjectType__c = null,
+				ObjectTypeAlternate__c = Schema.fflib_LogEntry__c.SObjectType.getDescribe().getName(),
+				BeforeInsert__c = true,
+				ImplementationType__c = 'fflib_TriggerHandlerTest.MyTriggerAction',
+				ExecutionContext__c = 'Realtime',
+				Stateful__c = true
+		);
+
+		fflib_TriggerHandler triggerHandler = new fflib_TriggerHandler();
+		String ctxClassName = triggerHandler.triggerContextType.getName() + '.Constructor';
+		fflib_TriggerContext ctx =
+				(fflib_TriggerContext)
+						((fflib_IDomainConstructor) Type.forName(ctxClassName).newInstance())
+								.construct(new List<fflib_LogEntry__c> {record});
+		ctx.triggerOperation = System.TriggerOperation.BEFORE_INSERT;
+
+		// WHEN a record is inserted
+		System.Test.startTest();
+		triggerHandler.addTriggerActionConfig(triggerAction);
+		triggerHandler.setTriggerContext(ctx).run();
+		System.Test.stopTest();
+
+		// THEN the stateful trigger action should be re-used
+		((fflib_ITriggerAction)	mocks.verify(triggerActionMock)).doWork();
+	}
 
 	public class MyTriggerAction extends fflib_TriggerAction // Todo - rename handler to action
 	{