Test run for Web Service Callout batch class

Question

I have an apex class which fetches and upserts data from external source to Salesforce.

Below is the batch class:

global class PolicyCalloutBatchClass implements Database.Batchable<Integer>,Database.AllowsCallouts, Database.Stateful {
    global Iterable<Integer> start(Database.BatchableContext context) {
        Integer[] values = new Integer[0];
        while(values.size() < 2999 || Test.isRunningTest()) values.add(values.size());
        return values;
    }
    global void execute(Database.BatchableContext context, Integer[] values) {
        
        HttpRequest policyreq = new HttpRequest();
        policyreq.setMethod('GET');
        policyreq.setTimeout(120000);
        policyreq.setEndpoint('<endpoint>');
        policyreq.setHeader('Authorization', 'Bearer ' + <token>);
        Http policyhttp = new Http();
        HTTPResponse policyres = policyhttp.send(policyreq);
        String policyresponse = policyres.getBody();
        JsonParser objJsonParser = (JsonParser) JSON.deserialize(policyresponse, JsonParser.class);  
        
        JsonParser.cls_value clsValue = objJsonParser.value;
        Map<String, JsonParser.cls_data> clsDataMap = new Map<String, JsonParser.cls_data>();
        for(JsonParser.cls_data objClsData: clsValue.data){
            clsDataMap.put(objClsData.id, objClsData);
        }
        list<Policy__c> updatelist = new list<Policy__c>();
        for (String eachIdFromMap : clsDataMap.keySet()){
            
            Policy__c policy = new Policy__c(
                unique_id__c = clsDataMap.get(eachIdFromMap).id,
                agent_id__c = clsDataMap.get(eachIdFromMap).agentId);
            updatelist.add(policy);  
        }
        try{
            upsert updatelist unique_id__c;    
        }
        catch(DmlException e){
            system.debug('This class didnt compile');
        }
    }
    global void finish(Database.BatchableContext context) {
        
    }
}

Below is my Mock test class:

@isTest
global class MockHttpResponseGenerator implements HttpCalloutMock {
    // Implement this interface method
    global HTTPResponse respond(HTTPRequest req) {
          HttpRequest policyreq = new HttpRequest();
        policyreq.setMethod('GET');
        policyreq.setTimeout(120000);
        policyreq.setEndpoint('<endpoint>');
        policyreq.setHeader('Authorization', 'Bearer ' + <token>);
        Http policyhttp = new Http();
        HTTPResponse policyres = policyhttp.send(policyreq);
        String policyresponse = policyres.getBody();
        
      
        return policyres;
    }
}

Below is my test class:

@isTest 
private class PolicyUpdateController_Test {
    static testMethod void testPostCallout() {
        Test.setMock(HttpCalloutMock.class, new MockHttpResponseGenerator());  
        
        Test.startTest();
      Database.executeBatch(new PolicyCalloutBatchClass(), 50); 
        Test.stopTest();
        
    }
}

Now, when I run the above test class, either the test class runs forever without any output or I could see the error as

System.LimitException: Too many callouts: 101

Can anyone please let me know if there is any way to get this done?

Thanks!

Answer 1

The issue is this condition:

    while(values.size() < 2999 || Test.isRunningTest()) {
        values.add(values.size());
    }

As you have given Test.isRunningTest() or values.size() < 2999 which is true, so it goes in infinite loop. and runs forever.

It should be:

Integer[] values = new Integer[0];
while(values.size() < 2999) {
    values.add(values.size());
}
if(Test.isRunningTest()) {
    values.clear();
    values.add(1);
}

Also your mock class is incorrect:

It should be :

global class MockHttpResponseGenerator implements HttpCalloutMock {
    // Implement this interface method
    global HTTPResponse respond(HTTPRequest req) {
        HttpResponse objHttpResponse = new HttpResponse();
        objHttpResponse.setBody('Ho');
        objHttpResponse.setStatusCode(200);
        return objHttpResponse;
    }
}

set the desired response and status code. Also not sure what are you doing with the values as I dont see any iteration happening, or do you just wanted the execute method to run multiple times.

Answer 2

The start() method runs into an infinite loop. The start() should return all records that need to be processed in the job. If your intention is to run 50 records a batch and cap it at 2999 (i.e. less than 60 batches), you could simply do:

return new Integer[2999];

Your HTTP mock class should simply focus on crafting the response body, not firing another HTTP callout.