The Apex Trigger Actions Framework allows developers and administrators to partition, order, and bypass record-triggered automations for applications built on Salesforce.com.
The framework supports both Apex and Flow - which empowers developers and administrators to define automations in the tool of their choice, then plug them together harmoniously.
With granular control of the relative order of execution of Apex vs. Flow and standardized bypass mechanisms, the framework enables an "Automation Studio" view of all automations for a given sObject.
With the Trigger Actions Framework, we use custom metadata to configure our trigger logic from the setup menu. The custom metadata defines:
- The sObject and context for which an action is supposed to execute
- The order to take those actions within a given context
- Mechanisms to determine if and when the action should be bypassed
The related lists on the SObject_Trigger_Setting__mdt record provide a consolidated and ordered view of all of the Apex and Flow actions that will be executed when a record is inserted, updated, deleted, or undeleted:
The Trigger Actions Framework conforms strongly to the Open–closed principle and the Single-responsibility principle. To add or modify trigger logic in our Salesforce org, we won't need to keep modifying the body of a TriggerHandler class; we can create a class or a flow with responsibility scoped to the automation we are trying to build and configure these actions to run in a specified order within a given trigger context.
The work is performed in the MetadataTriggerHandler class which implements the Strategy Pattern by fetching all Trigger Action metadata that is configured in the org for the given trigger context and uses reflection to dynamically instantiate an object that implements a `TriggerAction`` interface, then casts the object to the appropriate interface as specified in the metadata and calls the respective context methods in the order specified.
Note that if an Apex class is specified in metadata and it does not exist or does not implement the correct interface, a runtime error will occur.
To get started, call the MetadataTriggerHandler class within the body of the trigger of the sObject:
trigger OpportunityTrigger on Opportunity (
before insert,
after insert,
before update,
after update,
before delete,
after delete,
after undelete
) {
new MetadataTriggerHandler().run();
}Next, create a row in the SObject_Trigger_Setting__mdt custom metadata type which corresponds to the sObject that we want to enable usage of the framework on - in this case, it would be Opportunity.
To define a specific action, we write an individual class which implements the applicable interface(s):
public class TA_Opportunity_StageInsertRules implements TriggerAction.BeforeInsert {
@TestVisible
private static final String PROSPECTING = 'Prospecting';
@TestVisible
private static final String INVALID_STAGE_INSERT_ERROR = 'The Stage must be \'Prospecting\' when an Opportunity is created';
public void beforeInsert(List<Opportunity> newList){
for (Opportunity opp : newList) {
if (opp.StageName != PROSPECTING) {
opp.addError(INVALID_STAGE_INSERT_ERROR);
}
}
}
}Then create a row within the Trigger_Action__mdt custom metadata type to call the action in the specified order on the sObject.
The Apex Trigger Actions Framework can also allow you to invoke a flow by name, and determine the order of the flow's execution amongst other trigger actions in a given trigger context. Here is an example of a trigger action flow that checks if a record's name has changed and if so it sets the record's description to a default value.
To make your flows usable, they must be auto-launched flows and you need to create the following flow resource variables:
| Variable Name | Variable Type | Available for Input | Available for Output | Description | Available Contexts |
|---|---|---|---|---|---|
record |
record | yes | yes | the new version of the record in the DML operation | insert, update, undelete |
recordPrior |
record | yes | no | the old version of the record in the DML operation | update, delete |
To enable this flow, simply insert a trigger action record with Apex_Class_Name__c equal to TriggerActionFlow and set the Flow_Name__c field with the API name of the flow itself. You can select the Allow_Flow_Recursion__c checkbox to allow flows to run recursively (advanced).
Warning
Trigger Action Flows and Recursion Depth
- Key Point: Trigger Action Flows are executed using the
Invocable.Actionclass and are therefore subject to the (undocumented) "maximum recursion depth of 3" which is lower than the usual trigger depth limit of 16. - Why It Matters: This limit can be reached when Trigger Action Flows perform DML operations that cascade across multiple objects with their own Trigger Action Flows.
- When to Be Careful: Exercise caution when using Trigger Action Flows in scenarios involving multiple DML operations or complex trigger chains.
- Safe Use Cases: Same-record updates, using the
addErroraction to add a custom error message, and actions like workflow email alerts are generally safe. - Potential Solution (Developer Preview): This idea aims to reduce the likelihood of hitting the limit, but the technology is still under development.
Trigger Action Flows can also be used to process Change Data Capture events, but there are two minor modifications necessary:
| Variable Name | Variable Type | Available for Input | Available for Output | Description |
|---|---|---|---|---|
record |
record | yes | no | the changeEvent object |
header |
FlowChangeEventHeader (Apex Defined) |
yes | no | a flow-accessible version of the ChangeEventHeader object |
Create a trigger action record with Apex_Class_Name__c equal to TriggerActionFlowChangeEvent (instead of TriggerActionFlow) and set the Flow_Name__c field with the API name of the flow itself.
The Trigger Actions Framework supports standard objects, custom objects, and objects from installed packages. To use the framework with an object from an installed package, separate the Object API Name from the Object Namespace on the sObject Trigger Setting itself. For example, if you want to use the Trigger Actions Framework on an sObject called Acme__Explosives__c, configure the sObject Trigger Setting like this:
| Object Namespace | Object API Name |
|---|---|
| Acme | Explosives__c |
Use the TriggerBase.idToNumberOfTimesSeenBeforeUpdate and TriggerBase.idToNumberOfTimesSeenAfterUpdate to prevent recursively processing the same record(s).
public class TA_Opportunity_RecalculateCategory implements TriggerAction.AfterUpdate {
public void afterUpdate(List<Opportunity> newList, List<Opportunity> oldList) {
Map<Id,Opportunity> oldMap = new Map<Id,Opportunity>(oldList);
List<Opportunity> oppsToBeUpdated = new List<Opportunity>();
for (Opportunity opp : newList) {
if (
TriggerBase.idToNumberOfTimesSeenAfterUpdate.get(opp.id) == 1 &&
opp.StageName != oldMap.get(opp.id).StageName
) {
oppsToBeUpdated.add(opp);
}
}
if (!oppsToBeUpdated.isEmpty()) {
this.recalculateCategory(oppsToBeUpdated);
}
}
private void recalculateCategory(List<Opportunity> opportunities) {
//do some stuff
update opportunities;
}
}The framework provides standardized bypass mechanisms to control execution on either an entire sObject, or for a specific action.
To bypass from the setup menu, simply navigate to the sObject Trigger Setting or Trigger Action metadata record you are interested in and check the Bypass Execution checkbox.
These bypasses will stay active until the checkbox is unchecked.
You can bypass all actions on an sObject as well as specific Apex or Flow actions for the remainder of the transaction using Apex or Flow.
To bypass from Apex, use the static bypass(String name) method in the TriggerBase, MetadataTriggerHandler, or TriggerActionFlow classes.
public void updateAccountsNoTrigger(List<Account> accountsToUpdate) {
TriggerBase.bypass('Account');
update accountsToUpdate;
TriggerBase.clearBypass('Account');
}public void insertOpportunitiesNoRules(List<Opportunity> opportunitiesToInsert) {
MetadataTriggerHandler.bypass('TA_Opportunity_StageInsertRules');
insert opportunitiesToInsert;
MetadataTriggerHandler.clearBypass('TA_Opportunity_StageInsertRules');
}public void updateContactsNoFlow(List<Contacts> contactsToUpdate) {
TriggerActionFlow.bypass('Contact_Flow');
update contactsToUpdate;
TriggerActionFlow.clearBypass('Contact_Flow');
}To bypass from Flow, use the TriggerActionFlowBypass.bypass invocable method. You can set the Bypass Type to Apex, Object, or Flow, then pass the API name of the sObject, class, or flow you would like to bypass into the Name field.
| Flow | Invocable Action Setup |
|---|---|
 |
 |
The Apex and Flow bypasses will stay active until the transaction is complete or until cleared using the clearBypass or clearAllBypasses methods in the TriggerBase, MetadataTriggerHandler, or TriggerActionFlow classes. There are also corresponding invocable methods in the TriggerActionFlowClearBypass and TriggerActionFlowClearAllBypasses which will perform the same resetting of the bypass. To use these invocable methods, set the bypassType to Apex, Object, or Flow, then to clear a specific bypass set the API name of the sObject, class, or flow you would like to clear the bypass for into the name field.
Both the sObject_Trigger_Setting__mdt and the Trigger_Action__mdt have fields called Bypass_Permission__c and Required_Permission__c. Both of these fields are optional, but they can control execution flow for specific users.
Developers can enter the API name of a permission in the Bypass_Permission__c field. If this field has a value, then the trigger/action will be bypassed if the running user has the custom permission identified. This can be helpful when assigned to an integration service-account user to facilitate large data loads, or when assigned to a system administrator for a one-time data load activity.
Developers can enter the API name of a permission in the Required_Permission__c field. If this field has a value, then the trigger/action will only execute if the running user has the custom permission identified. This can allow for new functionality to be released to a subset of users.
It could be the case that multiple triggered actions on the same sObject require results from a query to implement their logic. In order to avoid making duplicative queries to fetch similar data, use the Singleton pattern to fetch and store query results once then use them in multiple individual action classes.
public class TA_Opportunity_Queries {
private static TA_Opportunity_Queries instance;
private TA_Opportunity_Queries() {
}
public static TA_Opportunity_Queries getInstance() {
if (TA_Opportunity_Queries.instance == null) {
TA_Opportunity_Queries.instance = new TA_Opportunity_Queries();
}
return TA_Opportunity_Queries.instance;
}
public Map<Id, Account> beforeAccountMap { get; private set; }
public class Service implements TriggerAction.BeforeInsert {
public void beforeInsert(List<Opportunity> newList) {
TA_Opportunity_Queries.getInstance().beforeAccountMap = getAccountMapFromOpportunities(
newList
);
}
private Map<Id, Account> getAccountMapFromOpportunities(
List<Opportunity> newList
) {
Set<Id> accountIds = new Set<Id>();
for (Opportunity myOpp : newList) {
accountIds.add(myOpp.AccountId);
}
return new Map<Id, Account>(
[SELECT Id, Name FROM Account WHERE Id IN :accountIds]
);
}
}
}Now configure the queries to be the first action to be executed within the given context, and the results will be available for any subsequent triggered action.
With the TA_Opportunity_Queries class configured as the first action, all subsequent actions can use TA_Opportunity_Queries.getInstance() to fetch the query results.
public class TA_Opportunity_StandardizeName implements TriggerAction.BeforeInsert {
public void beforeInsert(List<Opportunity> newList) {
Map<Id, Account> accountIdToAccount = TA_Opportunity_Queries.getInstance()
.beforeAccountMap;
for (Opportunity myOpp : newList) {
String accountName = accountIdToAccount.get(myOpp.AccountId)?.Name;
myOpp.Name = accountName != null
? accountName + ' | ' + myOpp.Name
: myOpp.Name;
}
}
}Note:
In the example above, the top-level class is the implementation of the Singleton pattern, but we also define an inner class called Service which is the actual Trigger Action itself. When using this pattern for query management, the Apex_Class_Name__c value on the Trigger_Action__mdt row would be TA_Opportunity_Queries.Service.
To avoid having to downcast from Map<Id,sObject>, we simply construct a new map out of our newList and oldList variables:
public void beforeUpdate(List<Opportunity> newList, List<Opportunity> oldList) {
Map<Id,Opportunity> newMap = new Map<Id,Opportunity>(newList);
Map<Id,Opportunity> oldMap = new Map<Id,Opportunity>(oldList);
...
}This will help the transition process if you are migrating an existing Salesforce application to this new trigger actions framework.
Performing DML operations is extremely computationally intensive and can really slow down the speed of your unit tests. We want to avoid this at all costs. Traditionally, this has not been possible with existing Apex Trigger frameworks, but this Trigger Action approach makes it much easier. Included in this project is a TriggerTestUtility class which allows us to generate fake record Ids.
@IsTest
public class TriggerTestUtility {
static Integer myNumber = 1;
public static Id getFakeId(Schema.SObjectType sObjectType) {
String result = String.valueOf(myNumber++);
return (Id) (sObjectType.getDescribe().getKeyPrefix() +
'0'.repeat(12 - result.length()) +
result);
}
}We can also use getErrors() method to test the addError(errorMsg) method of the SObject class.
Take a look at how both of these are used in the TA_Opportunity_StageChangeRulesTest class:
@IsTest
private static void invalidStageChangeShouldPreventSave() {
List<Opportunity> newList = new List<Opportunity>();
List<Opportunity> oldList = new List<Opportunity>();
//generate fake Id
Id myRecordId = TriggerTestUtility.getFakeId(Opportunity.SObjectType);
newList.add(
new Opportunity(
Id = myRecordId,
StageName = Constants.OPPORTUNITY_STAGENAME_CLOSED_WON
)
);
oldList.add(
new Opportunity(
Id = myRecordId,
StageName = Constants.OPPORTUNITY_STAGENAME_QUALIFICATION
)
);
new TA_Opportunity_StageChangeRules().beforeUpdate(newList, oldList);
//Use getErrors() SObject method to get errors from addError without performing DML
System.assertEquals(
true,
newList[0].hasErrors(),
'The record should have errors'
);
System.assertEquals(
1,
newList[0].getErrors().size(),
'There should be exactly one error'
);
System.assertEquals(
newList[0].getErrors()[0].getMessage(),
String.format(
TA_Opportunity_StageChangeRules.INVALID_STAGE_CHANGE_ERROR,
new List<String>{
Constants.OPPORTUNITY_STAGENAME_QUALIFICATION,
Constants.OPPORTUNITY_STAGENAME_CLOSED_WON
}
),
'The error should be the one we are expecting'
);
}Notice how we performed zero DML operations yet we were able to cover all of the logic of our class in this particular test. This can help save a lot of computational time and allow for much faster execution of Apex tests.
The Apex Trigger Actions Framework now has support for a novel feature not found in other Trigger frameworks; DML finalizers.
A DML finalizer is a piece of code that executes exactly one time at the very end of a DML operation.
This is notably different than the final action within a given trigger context. The final configured action can be executed multiple times in case of cascading DML operations within trigger logic or when more than 200 records are included in the original DML operation. This can lead to challenges when capturing logs or invoking asynchronous logic.
DML finalizers can be very helpful for things such as enqueuing a queuable operation or inserting a collection of gathered logs.
Finalizers within the Apex Trigger Actions Framework operate using many of the same mechanisms. First, define a class that implements the TriggerAction.DmlFinalizer interface. Include public static variables/methods so that the trigger actions executing can register objects to be processed during the finalizer's execution.
public with sharing class OpportunityCategoryCalculator implements Queueable, TriggerAction.DmlFinalizer {
private static List<Opportunity> toProcess = new List<Opportunity>();
private List<Opportunity> currentlyProcessing;
public static void registerOpportunities(List<Opportunity> toRecalculate) {
toProcess.addAll(toRecalculate);
}
public void execute(FinalizerHandler.Context context) {
if (!toProcess.isEmpty()) {
this.currentlyProcessing = toProcess;
System.enqueueJob(this);
toProcess.clear();
}
}
public void execute(System.QueueableContext qc) {
// do some stuff
}
}Then create a corresponding row of DML_Finalizer__mdt to invoke your finalizer in the order specified.
Finally, use the static variables/methods of the finalizer within your trigger action to register data to be used in the finalizer's execution.
public with sharing class TA_Opportunity_RecalculateCategory implements TriggerAction.AfterUpdate {
public void afterUpdate(
List<Opportunity> newList,
List<Opportunity> oldList
) {
Map<Id, Opportunity> oldMap = new Map<Id, Opportunity>(oldList);
List<Opportunity> toRecalculate = new List<Opportunity>();
for (Opportunity opp : newList) {
if (opp.Amount != oldMap.get(opp.Id).Amount) {
toRecalculate.add(opp);
}
}
if (!toRecalculate.isEmpty()) {
OpportunityCategoryCalculator.registerOpportunities(toRecalculate);
}
}
}Just like everything else within the Apex Trigger Actions Framework, finalizers can be bypassed to suit your needs. On the DML_Finalizer__mdt metadata record, use the Bypass_Execution__c checkbox to bypass globally and the Bypass_Permission__c/Required_Permission__c fields to bypass for specific users or profiles.
For static bypasses, call the bypass, clearBypass, isBypassed, and clearAllBypasses methods within the FinalizerHandler class.
Warning
DML Finalizers are brand new and should be considered as experimental. If you encounter any issues when using them, please create an issue on the GitHub repository.
DML Finalizers are not allowed to call any other DML operations; otherwise they wouldn't be able to guarantee their final nature. If a finalizer calls another DML operation, a runtime error will be thrown.
To ensure that cascading DML operations are supported, all configured finalizers within the org are invoked at the end of any DML operation, regardless of the SObject of the original triggering operation.
The FinalizerHandler.Context object specified in the TriggerAction.DmlFinalizer interface's execute method currently is empty; there are no properties on this object. We are establishing the interface to include the context to help future-proof the interface's specifications.
To use a DML Finalizer, the Apex Trigger Actions Framework must be enabled on every SObject that supports triggers and will have a DML operation on it during a transaction, and enabled in all trigger contexts on those sObjects. If DML is performed on an SObject that has a trigger that does not use the framework, the system will not be able to detect when to finalize the DML operation.
Detecting when to finalize the operation requires knowledge of the total number of records passed to the DML operation. Unfortunately, there is no bulletproof way to do this currently in Apex; the best thing we can do is to rely on Limits.getDmlRows() to infer the number of records passed to the DML operation.
This works in most cases, but certain operations (such as setting a System.Savepoint) consume a DML row, and there are certain sObjects where triggers are not supported like CaseTeamMember which can throw off the counts and remove our ability to detect when to finalize. In order to avoid this problem, use the TriggerBase.offsetExistingDmlRows() method before calling the first DML operation within your Apex.
Savepoint sp = Database.setSavepoint(); // adds to Limits.getDmlRows()
TriggerBase.offsetExistingDmlRows();
insert accounts;insert caseTeamMembers; // additions to Limits.getDmlRows() are not able to be automatically handled because there is no trigger on `CaseTeamMember`
TriggerBase.offsetExistingDmlRows();
update cases;Note
Please consider upvoting this idea to help avoid this quirky reliance on Limits.getDmlRows()
It could be the case that you have multiple DML operations in a row and you would like the system to wait to finalize until they are all complete. For example, in a Lightning Web Component's controller:
@AuraEnabled
public static void foo(){
Account acme = new Account(
Name = 'Acme'
);
insert acme; // finalizer is called here
Account acmeExplosives = new Account(
Name = 'Acme-Explosives',
ParentId = acme.Id,
);
insert acmeExplosives; // second finalizer is called here
}To facilitate these needs, call the TriggerBase.waitToFinalize() and TriggerBase.nowFinalize() methods:
@AuraEnabled
public static void foo(){
TriggerBase.waitToFinalize();
Account acme = new Account(
Name = 'Acme'
);
insert acme;
Account acmeExplosives = new Account(
Name = 'Acme-Explosives',
ParentId = acme.Id,
);
insert acmeExplosives;
TriggerBase.nowFinalize(); // single finalizer is called here
}Sometimes it is infeasible for the system to be told to waitToFinalize - for example: when the composite API is called. To make sure our finalizers can safely handle these scenarios, be sure to guard your finalizers against multiple invocations in one transaction by clearing out any collections of records you need to process:
public void execute(FinalizerHandler.Context context) {
if (!toProcess.isEmpty()) {
this.currentlyProcessing = toProcess;
System.enqueueJob(this);
toProcess.clear();
}
}