Apex Trigger to callout Rest API to external system when the EventType is updated then EventName also should be same as the eventtype

Hi @Sreelekha kanakala

Here is the updated code.

Trigger
trigger ServiceContractUpdate on ServiceContract (after update) {
    Set<Id> updatedContractIds = new Set<Id>();
    for(ServiceContract sc : Trigger.new) {
        if(sc.Event_type__c != Trigger.oldMap.get(sc.Id).Event_type__c || sc.Event_Name__c != Trigger.oldMap.get(sc.Id).Event_Name__c){
            updatedContractIds.add(sc.Id);
        }
    }
    if(!updatedContractIds.isEmpty()) {
        DataUpdater.callExternalAPI(updatedContractIds);
    }
}
Apexclass
public class DataUpdater {
    @future(callout=true)
    public static void callExternalAPI(Set<Id> updatedContractIds) {
        List<ServiceContract> updatedContracts = [SELECT Id, Event_Type__c, Event_Name__c FROM ServiceContract WHERE Id IN :updatedContractIds];
        HttpRequest req = new HttpRequest();
        req.setEndpoint('https://apigenerator.dronahq.com/api/J7Dq5w-n/data');
        req.setMethod('GET');
        Http http = new Http();
        HttpResponse res = http.send(req);
        System.debug('Response body: ' + res.getBody());
        if (res.getStatusCode() == 200) {
            try {
                // Deserialize the response into a list of DataUpdateWrapper objects
                List<DataUpdateWrapper> wrapperList = (List<DataUpdateWrapper>) JSON.deserialize(
                        res.getBody(), List<DataUpdateWrapper>.class
                );
                for (DataUpdateWrapper wrapper : wrapperList) {
                    for (DataUpdateWrapper.ExternalEvent event : wrapper.events) {
                        System.debug('Event Type from API: ' + event.eventType);
                        for (ServiceContract sc : updatedContracts) {
                            System.debug('Service Contract Event Type: ' + sc.Event_Type__c);
                            if (sc.Event_Type__c == event.eventType) {
                                sc.Event_Name__c = event.eventName;
                            }
                        }
                    }
                }
                if (!updatedContracts.isEmpty()) {
                    update updatedContracts;
                }
            } catch (Exception e) {
                System.debug('Exception: ' + e.getMessage());
            }
        } else {
            System.debug('HTTP Request failed with status code: ' + res.getStatusCode());
            System.debug('Response body: ' + res.getBody());
        }
    }
}
WrapperClass
public class DataUpdateWrapper {
    public Integer id;  // This corresponds to the "id" field in the JSON response
    public List<ExternalEvent> events;  // This corresponds to the "events" array in the JSON
    public class ExternalEvent {
        public String eventType;  // This corresponds to "eventType" in the JSON
        public String eventName;  // This corresponds to "eventName" in the JSON
    }
}

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