[SalesForce] Getting CalloutException when testing Batchable class with Callouts and HttpCalloutMock

I'm trying to write test code for a Batchable class that AllowsCallouts. I've written a lot of other test code that uses HttpCalloutMock classes, and planned to do so for this class as well.

And, per best practices, I'm setting up my test data before calling Test.startTest(). Even so, I get a CalloutException:

System.CalloutException: You have uncommitted work pending. Please commit or rollback before calling out

This somewhat makes sense, because my start() method passes a SOQL query to Database.getQueryLocator() and my execute() method makes the web callouts. I'm guessing that when my test method calls test.stopTest(), both start() and execute() run in the same context. In regular batch operation, they happen in separate contexts so there isn't any uncommitted work.

I intend to work around this by calling the methods directly, possibly even calling start() before Test.startTest(), and then using the returned Database.QueryLocator to get the list of records I'll pass into execute().

I don't like the fact that I'm not testing the batch size used by the static method that kicks off the batch with Database.executeBatch(), so I'll probably have that use a constant that I can reference from my test code to ensure it's using the same batch size.

Salesforce kind of addresses this in the "Asynchronous Apex and Mock Callouts" section of the Summer '13 Release Notes, but they don't make reference to Batchable classes with Callouts. They only talk about making callouts and testing Batchable classes in the same test method.

So, my question is whether there is a better way to write this test. I'm also throwing this out so others searching the site can learn about possible workarounds.

Best Answer

I know this is a 'hack' but you may be able to call your batchable class methods inside your testmethod without running in a Database.executeBatch(...); method call. I have done this for a customer who needed higher test coverage; their batch apex was simple and didn't require the batchable context to be set.

TestCode:-

    MyBatchableClass mbc = new MyBatchableClass();

        List<MySObject__c> scope = {list of previously inserted objects};
        mbc.execute(null, scope);
        Test.startTest();
        WebServiceMockImpl mock = new WebServiceMockImpl();

        Test.setMock(WebServiceMock.class, mock);
        //Webservice call out in here
        mbc.finish(null);

        Test.stopTest();

Related Solutions

[SalesForce] Test Batch that call HttpCallOut method using MultiStaticResourceCalloutMock

I think your issue is a known limitation - see my answer here from a while back. I have never found a combination of mock services and test.start/stop that lets you test a batch that contains a callout. I think your best bet is to move the callout to a separate class that you can test independently, and then have the batch check for a running test before calling it

[SalesForce] Testing a class that has multiple callouts

There are a couple of ways you can test this when you have more than one apex callout. Adopt any one of these approaches based on your preference.

1. Using MultiStaticResourceCalloutMock and Static Resources.

In this approach, you put mock responses in the static resource that is a text file with mock data in JSON format.

An example of this as below and can be found here in docs

@isTest
private class CalloutMultiStaticClassTest {
    @isTest static void testCalloutWithMultipleStaticResources() {
    // Use MultiStaticResourceCalloutMock to
    // specify fake response for a certain endpoint and 
    // include response body in a static resource.    
    MultiStaticResourceCalloutMock multimock = new MultiStaticResourceCalloutMock();
    multimock.setStaticResource(
        'http://example.com/example/test', 'mockResponse'); // mockResponse is a static resource file with mock response
    multimock.setStaticResource(
        'http://example.com/example/sfdc', 'mockResponse2'); // mockResponse2 is a static resource file with mock response
    multimock.setStatusCode(200);
    multimock.setHeader('Content-Type', 'application/json');
    
    // Set the mock callout mode
    Test.setMock(HttpCalloutMock.class, multimock);
    
    // Call the method for the first endpoint
    HTTPResponse res = CalloutMultiStaticClass.getInfoFromExternalService(
        'http://example.com/example/test');
    // Verify response received 
    System.assertEquals('{"hah":"fooled you"}', res.getBody());
    
    // Call the method for the second endpoint
    HTTPResponse res2 = CalloutMultiStaticClass.getInfoFromExternalService(
        'http://example.com/example/sfdc');
    // Verify response received 
    System.assertEquals('{"hah":"fooled you twice"}', res2.getBody());
  }
}

2. Creating a MultiRequest mock class that has a constructor that accepts Map<String, HttpCalloutMock> requests where the map key is the endpoint. The respond method responds based on the endpoint provided.

public class MultiRequestMock implements HttpCalloutMock {
Map<String, HttpCalloutMock> requests;

public MultiRequestMock(Map<String, HttpCalloutMock> requests) {
    this.requests = requests;
}

public HTTPResponse respond(HTTPRequest req) {
    HttpCalloutMock mock = requests.get(req.getEndpoint());
    if (mock != null) {
        return mock.respond(req);
    } else {
        throw new MyCustomException('HTTP callout not supported for test methods');
    }
}

  public void addRequestMock(String url, HttpCalloutMock mock) {
    requests.put(url, mock);
  }
}

check the complete example here

Best Answer

Related Solutions

[SalesForce] Test Batch that call HttpCallOut method using MultiStaticResourceCalloutMock

[SalesForce] Testing a class that has multiple callouts

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