APEX, Unit Test, Callout No Response with Static Resource - json

Question

Bit stuck on another one i'm afraid, i am trying to write a unit test for a bulk APEX class.
The class has a calllout to the google api, so i have created a static resource which i am feeding in via a mock, so i can complete testing of processing the JSON that is returned. However for some reason the response is always empty.
Now the very odd thing is that if i use exactly the same callout/JSON code, and the same mock code on a previous #future call, then it does return fine.
Here is the class:
global class mileage_bulk implements Database.Batchable<sObject>,
Database.AllowsCallouts
{
global Database.QueryLocator start(Database.BatchableContext BC)
{
String query = 'SELECT Id,Name,Amount,R2_Job_Ref__c,R2_Shipping_Post_Code__c,Shipping_Postcode_2__c FROM Opportunity WHERE R2_Shipping_Post_Code__c != null';
return Database.getQueryLocator(query);
//system.debug('Executing'+query);
}
global void execute(Database.BatchableContext BC, List<Opportunity> scope)
{
system.debug(scope);
for(Opportunity a : scope)
{
String startPostcode = null;
startPostcode = EncodingUtil.urlEncode('HP27DU', 'UTF-8');
String endPostcode = null;
String endPostcodeEncoded = null;
if (a.R2_Shipping_Post_Code__c != null){
endPostcode = a.R2_Shipping_Post_Code__c;
Pattern nonWordChar = Pattern.compile('[^\\w]');
endPostcode = nonWordChar.matcher(endPostcode).replaceAll('');
endPostcodeEncoded = EncodingUtil.urlEncode(endPostcode, 'UTF-8');
}
Double totalDistanceMeter = null;
Integer totalDistanceMile = null;
String responseBody = null;
Boolean firstRecord = false;
String ukPrefix = 'UKH';
if (a.R2_Job_Ref__c != null){
if ((a.R2_Job_Ref__c).toLowerCase().contains(ukPrefix.toLowerCase())){
system.debug('Is Hemel Job');
startPostcode = EncodingUtil.urlEncode('HP27DU', 'UTF-8');
} else {
system.debug('Is Bromsgrove Job');
startPostcode = EncodingUtil.urlEncode('B604AD', 'UTF-8');
}
}
// build callout
Http h = new Http();
HttpRequest req = new HttpRequest();
req.setEndpoint('http://maps.googleapis.com/maps/api/directions/json?origin='+startPostcode+'&destination='+endPostcodeEncoded+'&units=imperial&sensor=false');
req.setMethod('GET');
req.setTimeout(60000);
system.debug('request follows');
system.debug(req);
try{
// callout
HttpResponse res = h.send(req);
// parse coordinates from response
JSONParser parser = JSON.createParser(res.getBody());
responseBody = res.getBody();
system.debug(responseBody);
while (parser.nextToken() != null) {
if ((parser.getCurrentToken() == JSONToken.FIELD_NAME) &&
(parser.getText() == 'distance')){
parser.nextToken(); // object start
while (parser.nextToken() != JSONToken.END_OBJECT){
String txt = parser.getText();
parser.nextToken();
//system.debug(parser.nextToken());
//system.debug(txt);
if (firstRecord == false){
//if (txt == 'text'){
//totalDistanceMile = parser.getText();
system.debug(parser.getText());
//}
if (txt == 'value'){
totalDistanceMeter = parser.getDoubleValue();
double inches = totalDistanceMeter*39.3701;
totalDistanceMile = (integer)inches/63360;
system.debug(parser.getText());
firstRecord = true;
}
}
}
}
}
} catch (Exception e) {
}
//system.debug(accountId);
system.debug(a);
system.debug(endPostcodeEncoded);
system.debug(totalDistanceMeter);
system.debug(totalDistanceMile);
// update coordinates if we get back
if (totalDistanceMile != null){
system.debug('Entering Function to Update Object');
a.DistanceM__c = totalDistanceMile;
a.Shipping_Postcode_2__c = a.R2_Shipping_Post_Code__c;
//update a;
}
}
update scope;
}
global void finish(Database.BatchableContext BC)
{
}
}
and here is the test class;
#isTest
private class mileage_bulk_tests{
static testMethod void myUnitTest() {
Opportunity opp1 = new Opportunity(name = 'Google Test Opportunity',R2_Job_Ref__c = 'UKH12345',R2_Shipping_Post_Code__c = 'AL35QW',StageName = 'qualified',CloseDate = Date.today());
insert opp1;
Opportunity opp2 = new Opportunity(name = 'Google Test Opportunity 2',StageName = 'qualified',CloseDate = Date.today());
insert opp2;
Opportunity opp3 = new Opportunity(name = 'Google Test Opportunity 3',R2_Job_Ref__c = 'UKB56789',R2_Shipping_Post_Code__c = 'AL35QW',StageName = 'qualified',CloseDate = Date.today());
insert opp3;
StaticResourceCalloutMock mock = new StaticResourceCalloutMock();
mock.setStaticResource('googleMapsJSON');
mock.setStatusCode(200); // Or other appropriate HTTP status code
mock.setHeader('Content-Type', 'application/json'); // Or other appropriate MIME type like application/xml
//Set the mock callout mode
Test.setMock(HttpCalloutMock.class, mock);
system.debug(opp1);
system.debug(opp1.id);
//Call the method that performs the callout
Test.startTest();
mileage_bulk b = new mileage_bulk();
database.executeBatch((b), 10);
Test.stopTest();
}
}
Help greatly appreciated!
Thanks
Gareth

Answer 1

Not certain what 'googleMapsJSON' looks like, perhaps you could post for us.
Assuming your mock resource is well formatted, make sure the file extension is ".json" and was saved with UTF-8 encoding.
If #2 does not work, you should try saving your resource as .txt - I've run in to this before where it needed a plain text resource but expected application/json content type
Be certain that the resource name string you are providing has the same casing as the name of the resource. It is case sensitive.
Are you developing on a namespaced package environment? Try adding the namespace to the resource name if so.
Otherwise, your code looks pretty good at first glance.