Is there a way to retrieve the oldMap of a trigger in a future method?

Question

This could be quite a dumb question though, I would like to ask is there a way to retrieve the oldMap of a trigger in a @future method?

In the below code please refer the collection "oldReportsMap", Can I refer the old map of the record Ids?

BELOW CODE IS THE EXSISTING ONE AND NEED TO MAKE GENERIC FOR MULTIPLE OBJECTS
/*
 * Populate acount fields on creation of the Report record.
 */
public class updateAccountFields implements Triggers.Handler {
    public void run(){
        
        if (!(Trigger.isAfter && Trigger.isInsert)) { return; }
        
        List<Report__c> triggerReports = (List<Report__c>) Trigger.new;
        Set<Id> reptIds = new Set<Id>();
        
        for (Report__c report: triggerNewReports) { 
            reptIds.add(report.id);
        }

        // process accounts fields
        if (Test.IsRunningTest()) {
            processUpdateAccountFields(reptIds);
        } else {
            processUpdateAccountFieldsFuture(reptIds);
        }
        
    }
}

@future
public static void processUpdateAccountFieldsFuture(Set<ID> reptIds) {
    processUpdateAccountFields(reptIds);
}

/*
 * Populate account fields on creation of the Report record.
 */
public static void processUpdateAccountFields(Set<ID> reptIds) {   
    Set<Id> acctIds = new Set<Id>();
    
    Map<Id, Report__c> reports = new Map<Id, Report__c>([SELECT Id, ReceivedDate__c, DueDate__c, Account__c FROM Report__c WHERE id IN: reptIds]);
    
    // retrieve the related accounts
    for (Report__c report: reports) { 
        acctIds.add(report.Account__c);
    }
    
    Map<Id, Report__c> oldReportsMap = new Map<Id, Report__c>([SELECT Id, ReceivedDate__c, DueDate__c, Account__c FROM Report__c WHERE id IN: ????]);
    
    for(Id reptId :  oldReportsMap.keyset()){
        ... some more code...
    }
    .... Some more code/logic....
}

Thanks

UPDATE:

Unfortunately serialization doesn't work for me it takes considerable amount of time to serialize the old object, and I have an sObject which could be a standard object or a custom object depends on the sObjectType. eg: our account object has 943 fields at the moment. I do not want to serialize all account object's fields just to track one field change. so far what I could see is, according to my scenario, there is no way of accessing oldMap since it is not in the trigger context when at a future call.

• I found that there is an idea to for an isChangefunctionality for apex.
• please note that our org gets updates for multiple objects via webservice API and this could update considerable number of records at a one call, which leads to a timeout the service request due to above mention issue.

Thanks all for your support!

Answer 1

If the poor performance of the serialization process is a roadblock for you, I recommend you create a Queueable implementation instead of using @future. It would look something like:

public with sharing class MyAsyncProcessor implements Queueable
{
    final Map<Id, Report__c> oldMap;
    public MyAsyncProcessor(Map<Id, Report__c> oldMap) { this.oldMap = oldMap; }
    public void execute(QueueableContext context)
    {
        // run your logic here
    }
}

Then in your trigger/handler, you would just do something like:

system.enqueueJob(new MyAsyncProcessor(trigger.oldMap));