Callout from APEX Triggers
This tutorial shows how to make HTTP callout from an APEX trigger using
Future method.
Step 1: Create Apex Class
First step is to create an apex class.
After you login, click on Setup > Develop > Apex Classes > New.
Step 2: Write future method
Write future method that calls external service.
public class AccountUpdater {
//Future annotation to mark the method as async.
@Future(callout=true)
public static void updateAccount(String id, String name) {
//construct an HTTP request
HttpRequest req = new HttpRequest();
req.setEndpoint('http://cheenath.com/tutorial/sfdc/sample1/data.txt');
req.setMethod('GET');
//send the request
Http http = new Http();
HttpResponse res = http.send(req);
//check the response
if (res.getStatusCode() == 200) {
//update account
Account acc = new Account(Id=id);
acc.Description = res.getBody();
update acc;
} else {
System.debug('Callout failed: ' + res);
}
}
}
Step 3: Add external server to Remote Sites
Click Setup > Security Controls > Remote Site Settings > New
Add external site name and endpoint URL
Step 4: Create APEX trigger
Click Setup > Customize > Accounts > Triggers > New
And create the following trigger:
trigger descriptionUpdater on Account (after insert) {
System.debug('Making future call to update account');
for (Account acc : Trigger.New) {
//Call future method to update account
//with data from external server.
//This is a async calls, it returns right away, after
//enqueuing the request.
AccountUpdater.updateAccount(acc.Id, acc.Name);
}
}
Step 5: Test by creating a new Account
Click Accounts Tab > New
Enter Account Name and hit save.
Step 6: Check Async Apex Jobs
Click Setup > Monitoring > Apex Job
This will display the list of Async Apex Jobs enqueued. Wait till the status of the job just submited change to completed.
Step 7: Make sure the account is updated
Go back to the account we just created. The description of this account should now be updated with the data from external server.
Problems?
If you have any problem running this sample please post a message
here.
