History is in Detail! - Migrating Master-Detail Relationship with History Tracking on Child Object

Problem

Over the years as Force.com developer, I found that migration and trigger are two area where I encountered issues most frequently, and here is another interesting issue with migration in Salesforce.  I had a custom sObject that were in Master-Detail relationship with Account.  When I tried to migrate this object using Force.com Migration Tool, I was getting following error:

duplicate value found <unknown> duplicates value on record with id: <unknown> 

After much googling, I found this post on StackExchange, indicating that History Tracking might be a problem.  When I disabled the history tracking on the object, I was able to migrate the object.

Work-around
With the cause of the problem tracked down, I still found the prospect of manually enabling history tracking on the object and each field in the destination org quite troubling.  With Salesforce.com migration, some manual steps are unavoidable (e.g. Community setup, Quote enablement, etc.), but you do want to minimize the manual steps as much as possible, and I thought there might be a way to automate this step using Force.com Migration Tool.

First solution I considered was creating the object first with a lookup relationship with Account, then have another deployment of the same object with relationship change to Master-Detail relationship.  This did eliminate the "duplicate value..." error, but the problem was that when you change a relationship from Lookup to Master-detail (or vice-versa), it triggers sharing rule recalculation, which causes problem if you had any sharing rule being migrated at the later stage of the deployment step, which we did have for this project.

The eventual solution I came up with was a three-staged migration of the object.  First, I migrated a shell Metadata of the child object with Master-Detail Relationship on, but with history tracking turned off.  Second,  I migrated the shell Metadata file again, but with history tracking turned on.  Finally, I migrated the full retrieval of the child object Metadata.  One issue you have is that you have to manually maintain copies of shell Metadata files for these children objects, but schema for the shell is quite simple and you only have to create these shell files only once, whereas you have to perform manual step, which is prone to error, on every environment you migrate to.

I have checked in the code for the simplified version of this process in my github repository.  You can find it at https://github.com/jpaek/MasterDetailWithHistory.

Takeaway

The error message for this problem was rather misguiding for me, but this shouldn't come as a surprise to us Force.com developers, especially when working with migration.  Googling, as was case here, can help figure out what the problem is, but sometime you do have to manually figure out the problem by playing around with it, which can be quite cumbersome tasks.

Also, I want to point out that, with bit of thinking and experimentation, you can eliminate many of the manual steps involved with migration steps through Force.com Migration Tool.   

Task Trigger and Ugly Un-bulkfiication.

Problem

We had created a trigger on Case Task that would update a custom description field on the parent case with comment from the task when the status of the task changes to "closed."  This trigger worked at the beginning, but then this trigger started to fail with following error message:

Apex Task trigger cannot handle batch operations on recurring tasks.

It turns out that you cannot to have a trigger on event (including task) if you have any batch job on recurring events (see here) and that another team working with this client had implemented a batch apex job that managed recurring tasks related to some other object.  

Work-around

There really wasn't a work-around for this issue.  What we ended up doing was getting rid of the trigger and let user manually copy the value.

Takeaway

Trigger is one of the most problematic aspect of Salesforce.com development with many nuances, this being one of them.  With the release of the new Lightning Process Builder, we finally may have a work-around on this issue and many other trigger-related issues, although I cannot say that with high confidence as this very new feature with Salesforce.com.

Mobile Design Template and Angular.JS

Problem

We had implemented a multi-step wizard for our client.  Two of the requirements for this wizard was that it needed to be mobile-friendly, and it needs to have bilingual support.  To meet this requirement I had tried to implement a mobile version of the wizard using Mobile Design Templates.   I had previously built a simple mobile-friendly Visualforce page using Mobile Design Templates and Underscore.JS following the Getting Started with Mobile Design Templates blog post from Salesforce.

Given the complexity of this application, I had used Angular.JS as the back-end.  However, I ran into trouble when I tried to incorporate the Mobile Design Templates' toggle input into this application.

We had this picklist field with two values that we want to render as a toggle input.  To do so I had the Angular.JS controller called the service that would grab the labels for those two values from Salesforce, in order to meet the bilingual requirement, and set those label as data-on-label and data-off-label.

(function() {

var app = angular.module('app', []);



 app.controller('InputCtrl', function InputCtrl(InputLabelService) {

        var inputScope = this;



        // Get the label of the input form from Salesforce
        InputLabelService.getFormValues().then(
            function(picklists) {
                inputScope. inputLabels = picklists. inputLabels;


               // This renders the toggle input
               $(document).trigger('onTemplateReady');
        });
    });
})();

<section class="border-bottom">

    <div class="content">

    <h3>Input</h3>

        <div class="form-control-group">

            <div class="form-control form-control-toggle" data-on-label="{{inputLabels[0]}}" data-off-label="{{inputLabels[1]}}">

                <input type="checkbox" name="toggle">

             </div>

         </div>

     </div>

 </section>

The problem was that Mobile Design Templates render data-on-label and data-off-label on the toggle input upon the call to 'onTemplateReady' Javascript trigger.  However, because how the two-way binding of Angular.JS is done, the rendering of the toggle input is done before Angular.JS can set the data-on-label and data-off-label with appropriate values, which ended up rendering the toggle input without any label.

Solution

The way I had gotten around this issue was by putting a $watch listener on the inputLabels and to trigger 'onTemplateReady' when it has a new value.

(function() {

var app = angular.module('app', []);



 app.controller('InputCtrl', function InputCtrl(InputLabelService) {

        // Get the label of the input form from Salesforce
        InputLabelService.getFormValues().then(
            function(picklists) {
                $scope.inputLabels = picklists.inputLabels;



                $scope.$watch('inputLabels', function(newVal, oldVal) {



                    if (newVal) {

                       // This renders the toggle input
                       $(document).trigger('onTemplateReady');
                   }
               });
        });
    });
})();

Takeaway

In the end, I actually ended up not using Mobile Design Templates as the tabbed navigation, which I had used in one of the page, didn't work in iPhone.  Instead, I ended up using Bootstrap along with Angular.JS.  I still think Mobile Design Templates is a good tool to have in your tool belt if you are building a very simple mobile application on Salesforce1; however, for any application with a moderate complexity, I would definitely look at alternative, such as Bootstrap I have used for this project or Ionic Framework.

Way in the @future - Problem of using Salesforce as Real-time Relay System

Problem

For one of the project I was on, we had following as one of the requirements.  In this requirement, the System 1 would send a record to Salesforce, which would store the record, transform it based on the data stored in Salesforce and transmit the transformed record to System 2.  The whole process from System 1 to System 2 need to take less than 5 minute to complete.

Originally, we had implemented a trigger on the creation of the original record - Record A - that would transform it and send the transformation - Record A" - to System 2 by calling a web service through a future method.

This has been working as expected for quite sometime.  However, the production org was on NA14, and when the NA14 performance degradation occurred last year, we were witnessing that this request was taking more than half hours, and sometimes more than several hours.

Our investigation revealed that the problem was that the request to the future method gets stuck in the Apex Job Queue due to the degradation issue.  We had investigated both the batch apex and outbound-message workflow, but the problem was that both batch Apex and outbound-message jobs are queued the same way as the future method was.


Workaround

The way we addressed this problem was by implementing a custom web service.  This web service stored the Record A into Salesforce as well as transform the record the same way the trigger was doing.  We had proposed two solutions on how to transmit the transformed record to system 2.  One was for the custom web service make a callout; the second was to return the transformed record to System 1 as the response to the web service call, and System 1 would transmit it to System 2.  Our test revealed that both methods eliminated the queueing issue; however, the client went with the second option given the importance of this process.

Takeaway

The takeaway for me was that Salesforce really isn't a ideal tool for implementing a real-time processing of data, especially if you are using one of asynchronous methods (@future method, batch apex, etc.) as Salesforce do not provide any SLA on the timeliness of these processes.