NodeJS & AWS Lambda

NodeJS is a backend runtime environment that runs on the V8 engine and enables us to write and execute server-side JavaScript.

Use promises instead of callbacks

NodeJS was originally built using a callback pattern for asynchronous calls. All of NodeJS’s builtins are structured this way: you provide the main arguments along with a callback function that is applied when the asynchronous operation is done.

Fortunately, it’s quite easy to convert these methods to using promises instead. Let’s look at two different ways.

Using promisify

You can use a utility function, promisify, from the utils module to wrap the function using a callback in a promise.

It works for all functions that follow the NodeJS callback convention, which means that it works for a range of old third-party libraries for NodeJS as well.

Using module/promises

Instead of handling the promise-wrapping yourself, all NodeJS builtins come with a promisified version of their functions, straight from the module itself. This is, by far, the easiest way to use promises in NodeJS. Please, stick to this pattern anywhere you can.

Async handlers in AWS Lambda

The same goes for AWS Lambda. You don’t have to use the callback argument anymore. Instead, declare the handler as async, and return the result instead.

If you need to fulfill promises during the function call, you simply apply the await keyword like you normally would.

Salesforce Lightning: Assign a record to yourself

Let's assume that you want to assign an account or multiple account records to yourself from the detail record view and the list view respectively. You can easily implement the same using only flows if you want to take up a declarative approach.

I have created an autolaunched flow which accepts both single and multiple record ids. Care should be taken that the name of the variables should be exactly id and ids respectively.

To call this flow, create a custom button each for detail and list page and add it on the layout pages. So for the detail page, set the id flow variable to be the account ID, and once the flow is completed, redirect the user to the same account detail page by providing the retURL parameter in the flow URL.

For the list view page, make sure that Display Checkboxes is selected. The ids variable is populated automatically when one or more records are selected in the list view page. The only caveat is that once the flow is completed, I couldn't find a declarative way to redirect the user to the same list view page from where the flow was executed (you can use a Visualforce page to redirect to the list view). So for the sake of simplicity, I am redirecting the user to the Recently Viewed Accounts page.

Next, we have to add these buttons. To add the button on the detail page layout,

and to add on the list view page,

You can get the flow and the associated custom buttons files from this repository.

Salesforce Classic: Assign a record to yourself

Let's consider a use case where you want to assign a record (in this case, Workorder) to yourself. To implement this scenario, click on New Button or Link button. Enter the details as below:

and provide the below script:

{!REQUIRESCRIPT("/soap/ajax/49.0/connection.js")}
{!REQUIRESCRIPT("/soap/ajax/49.0/apex.js")}

var __sfdcSessionId = '{!GETSESSIONID()}';
sforce.connection.sessionId = __sfdcSessionId;

var workOrder = new sforce.SObject("WorkOrder");
workOrder.Id = "{!WorkOrder.Id}";
workOrder.OwnerId = sforce.connection.getUserInfo().userId;
result = sforce.connection.update([workOrder]);
 
if (result[0].getBoolean("success")) {
    console.log(result[0].id + " updated");
} else {
    console.log("failed to update " + result[0]);
}
window.location.reload();

Now add this button on the page layout.

Improving Salesforce Apex Performance

Improving CPU Time

In general, there are two ways to improve the CPU usage:

• Work on a smaller amount of data (that is, do less work).
• Operate on the data in a more efficient manner.

Faster for loops

In the following code snippet, we are using the SOQL for loop format to loop through the account records and a traditional iterator-style for loop:

List<Account> accs = AccountSelector.getAccounts();

Integer max = accs.size();
for (Integer i = 0; i < max; i++) {
   System.debug(accs[i].Name);
}

for (Account acc : AccountSelector.getAccounts()) {
   System.debug(acc.Name);
}

As per the tests, the iterator loop runs faster than the SOQL for loop. Therefore, we should use the iterator format for best performance in CPU time, though we do use a lot more heap size in the iterator.

This is an important example that highlights the fact that when optimizing for one governor limit, we will often impact another.

Using maps to remove and reduce looping

The simplest use case is when retrieving a list of records from a query and then putting them into a map so that you can retrieve a record using its ID.

Map<Id, Account> accsById = new Map<Id, Account>([SELECT Id, Name FROM Account]);
Account myAccount = accsById.get(myAccountId);

Reducing the use of expensive operations

If we wanted to retrieve the Name field of our account record and assign its value to a variable, we could do it in one of two ways. We could either call the Name field using a static reference or call the get method on the record, passing in the field name.

String accName = acc.Name;
String accountName = (String)acc.get('Name');

The second option is slower and more CPU intensive than the first one.

Another commonly used dynamic call is to the Schema class to retrieve information about metadata within the org. The simplest way to handle these situations is to cache values locally in variables for reuse. If you are making repeated calls to any of that describe information, you should work to cache these results in a local variable outside the loop, which will remove the need to make repeated calls and reduce your CPU time overall.

Reducing Heap Size Usage

The heap size is the amount of memory being used to store the various objects, variables, and state of the Apex transaction in memory as it is being processed. For synchronous operations, this is capped at 6 MB and is doubled to 12 MB for asynchronous processes.

Using scoping

We can either declare variables at a class level or within a code block (a method, loop, and so on) within Apex. Declaring a class-level variable means that the variable will be available in memory for the lifetime of the instance of that class, while variables declared in a code block will only be available for the scope of that block.

Structuring your code well into discrete functions with limited scope will help to ensure that your code avoids the heap size limit by allowing the Apex memory manager to handle memory effectively.

Removing unwanted items

Let’s refer the code snippet for the traditional iterator-style for loop we had used earlier. A simple action of setting the value of the accs variable to null reduces the heap size we are consuming.

List<Account> accs = AccountSelector.getAccounts();

Integer max = accs.size();
for (Integer i = 0; i < max; i++) {
   System.debug(accs[i].Name);
}
accs = null;

It can be useful therefore to remove any unwanted items from memory manually if you are working with large sets of data or the Blob data type and wish to free space to ensure that you do not hit the heap size limit. Combining this with scoping will help you ensure that the memory of your applications is well managed and, in most instances, you will have no concerns with the heap size limit.

Improving Query Selectivity

In order to achieve the best performance possible, we want to make our query as selective as possible to reduce the number of records returned.

The first thing that indicates selectivity is whether the field is indexed. The following types of field are indexed:

• Standard primary keys (Id, Name, OwnerId)
• Foreign key fields (CreatedById, LastModifiedById, lookup relationships, master-detail relationships)
• Audit fields (CreatedDate, SystemModstamp)
• Custom fields marked as unique or External Id

If a field is indexed, it will be considered for optimization. Following this, the optimizer then determines how many records are returned using that index. The following calculation is made to determine whether the number of records selected is below the following thresholds:

• For standard indexes, 30 percent of the first million targeted records and 15 percent of the remaining records. The threshold is 1 million records.
• For custom indexes, 10 percent of the first million targeted records and 5 percent of the remaining records. The threshold is 333,333 records.

If the indexed field meets these thresholds, it is considered selective and will be considered for optimization. Salesforce provides developers with the Query Plan tool in the Developer Console that will provide detailed information on whether a query is selective or not. To enable this in the Developer Console, open the Preferences menu and select the Enable Query Plan option. Once you have selected this option and saved, using the Query Editor pane, you can enter a query and use the Query Plan button to view metrics on the selectivity of a query. The statistics returned here inform us of which filter would be used (if any) and why. The columns presented have the following information:

• Cardinality: The number of records returned by this operation.
• Fields: The indexed fields used by the optimizer in this operation. This will be null if the field is not indexed.
• Leading Operation Type: The primary operation used by the optimizer to optimize the query, one of either Index for an indexed field, Sharing for sharing rule-based control, TableScan if a full search of the object occurs, and Other if an internal Salesforce optimization is used.
• Cost: This is a cost score for running the query. Any value over 1 is considered non-selective. We should always aim to have a query with a cost of 1 or less.
• sObject Cardinality: The approximate, number of records on the object.
• sObject Type: The object we are querying.

The other key practice when defining WHERE filters is to attempt to use positive/ inclusion operations (IN, =) rather than negative/exclusion operators (NOT, !=) as these exclusion operations are not optimizable, except when using != null and != boolean. It is a good practice therefore to ensure wherever possible that you use positive/inclusion operations to improve optimization chances.

Number of Queries

There are also a couple of simple ways in which you can reduce the number of queries you are running.

Retrieving child records with a sub query

If retrieving a record and you require child records, consider using a sub query where appropriate to help retrieve all the necessary data at once. This is not always necessarily a good practice; for example, when determining the Batch Apex scope, it is more performant to select the parent records in the batch scope and retrieve the child records in each batch. If you are working with a selective query on the parent record and retrieving a small set of data for each returned record, then this can help avoid additional loops, mapping, and queries.

Cache results

If the data is not expected to change during the transaction, a developer can use the singleton pattern to cache results that were retrieved. This is an extremely effective tool when retrieving setup-related objects (Profile, Holiday, Role) or custom metadata or custom settings. None of these items should change during the course of a transaction and are slow-moving data, making them comfortably cacheable for the duration of the transaction.

Platform Cache

Platform Cache is a powerful feature that can enhance the performance of applications when working at scale and requiring data to be retrieved in a regular fashion, but that does not change regularly. A free allocation of 10 MB of cache is provided for Enterprise Edition orgs, and 30 MB for Unlimited and Performance Edition, with a greater allowance available for purchase. If you are working in an environment where there is a set of data that is retrieved regularly but does not change, and you have available a Platform Cache allocation, then consider it as a possible enhancement to help improve your system's performance.

Access Grant, Share and Maintenance Tables

Record Access Calculation

As there are many options for managing record level access, and as some of these options are affected by organizational dependencies, determining which records users can access can quickly become complicated. Rather than checking record access in real time, Salesforce calculates record access data only when configuration changes occur. The calculated results persist in a way that facilitates rapid scanning and minimizes the number of database table joins necessary to determine record access at runtime.

Access Grants

When an object has its OWD set to Private or Public Read Only, which is not the least restrictive option, Salesforce uses access grants to define how much access a user or group has to that object’s records. Each access grant gives a specific user or group access to a specific record, It also records the type of sharing tool: sharing rule, team, etc.

Salesforce uses 4 types of access grants:

Explicit grants:

Grants that occur when records are shared directly to users or groups. Examples:

• A user or a queue becomes the owner of a record, as in Salesforce each record should have an owner, and whenever a record is owned by a user or a queue, an explicit share is used to grant access to the record for the owner or queue.
• A sharing rule shares the record to a personal or public group, a queue, or a role.
• An assignment rule shares the record to a user or a queue.
• A territory assignment rule shares the record to a territory.
• A user manually shares the record to a user, a personal or public group, a queue, or a role.
• A user becomes a part of a team for an account, opportunity, or case.
• A programmatic customization shares the record to a user, a group, or queue, or a role.

Group membership grants:

Grants that occur when a user, group, queue, role, or territory is a member of a group that has explicit access to the record. So as you know by now, an explicit share is used to grant access to group via sharing rules, manual sharing or Apex sharing, because of which all members of a group are granted access using the group membership access grant. For example, if a sharing rule grants the “Sales group” access to the Acme account record, and Bob is a member of the “Sales group”, Bob’s membership in the “Sales group” grants him access to the Acme account record.

Inherited grants:

Grants that occur when a user, group, queue, role, or territory inherits access through a role or territory hierarchy or is a member of a group that inherits access through a group hierarchy. For example, if a user Alice has a role that is higher in the role hierarchy than the role of another user Bob, then Alice can access the same records that Bob can access.

Implicit grants:

Grants that occur when non-configurable record-sharing behaviours built into Salesforce Sales, Service and Portal applications grant access to certain parent and child records. Examples:

• Read-only access to the parent account for a user with access to a child record.
• Access to child records for the owner of the parent account record.
• Access to a community account and all associated contacts for all community users under than account
• Access to data owned by community users associated with a sharing set for users member of the sharing set’s access group.

Object Share tables store the data that supports explicit and implicit grants.

SELECT Id, ParentId, UserOrGroup.Name, AccessLevel, RowCause FROM AccountShare

Group maintenance tables store the data that supports group membership and inherited access grants.

SELECT Id, Name, DeveloperName, Type, OwnerId FROM Group