Lightning Data Services : Way to perform operation on records without using server-side Apex class

Today I am going to walk through a new feature introduced by Salesforce - Lightning Data Services.
This is not yet generally available. It is available as developer preview.

What is lightning data services?

Lightning data services allows you to view, create, update and delete a record without using server-side Apex controllers. You can compare this with Standard Controller on VF page which allows you to read, create, update or delete records by providing in built functions like Save, Edit,Delete etc.

Other benefit of using Lightning data services is that all records are cached and shared across all components. This improves the performance because record is loaded only once.
If any component modifies the record, then other component using this records get notified and refresh automatically.

In order to use Lightning data services, you need to use force:recordPreview tag and need to specify recordId while performing any operation.

Now we will cover how to use Lightning data services for different operations.

• Load Record (View Record)

In order to Load record information on lightning component, you need to pass recordId. It is similar to pass id parameter in URL in VF page while using standard controller.

<force:recordData aura:id="recordLoader"

  recordId="xxxxxxxxxxxxx"

  layoutType="FULL"

  targetRecord="{!v.record}"
    targetFields="{!v.recordInfo}"

  targetError="{!v.recordError}"

  />

Before Summer'17 below was syntax which is now depricated.

<force:recordPreview aura:id="recordLoader"

 recordId="xxxxxxxxxxxxx"

 layoutType="FULL"

 targetRecord="{!v.record}"

 targetError="{!v.recordError}"

 />

recordId: It is 15 or 18 digit recordId.

targetRecord:  This contains complete info about record.
targetFields : A simplified view of the fields in targetRecord, to reference record fields in component markup.

targetError : This specify any error if lightning data services is not successfull in geting record details based on recordId provided.

• Edit Record

For editing records, you need use same  force:recordPreview tag and you can use additional attribute mode to specify you are editing record.

<force:recordData aura:id="recordHandler"

 recordId="xxxxxxxxxxxx"

 layoutType="FULL"

 targetRecord="{!v.record}"
     targetFields="{!v.recordInfo}"

 targetError="{!v.recordError}"

 mode="EDIT"

 />

Once you get access to record returned by Lightning Data Services in target record, then you can refer it in component to edit its field values. In order to Save the changes performed on record returned by Lightning data services, you can call javascript function to update records in database. In javascript function, you do not need to call apex class methods to update record but use functions provided by Lightning data services framework to perform this operation.

Below is javascript function code :

({
    SaveRecord: function(component, event, helper) {
        component.find("recordHandler").saveRecord($A.getCallback(function(saveResult) {
            if (saveResult.state === "SUCCESS" || saveResult.state === "DRAFT") {
//record got updated in salesforce
                // Reload the view so that all components are refreshed after update
                $A.get("e.force:refreshView").fire();
            }
            else {
var errMsg = 'Unknown problem, state: ' + saveResult.state + ', error: ' +         JSON.stringify(saveResult.error);
                console.log(errMsg);
alert(errMsg);
            }
        }));
    },
})

Remember recordHandler is aura:id of  force:recordData tag

• Create Record

For creating a new record, you need to use same force:recordPreview tag but no need to specify the recordId attribute.

<force:recordData aura:id="accountRecordCreator"

        layoutType="FULL"

        targetRecord="{!v.newAccount}"
       targetFields="{!v.newAccountInfo}"

        targetError="{!v.newAccountError}"

        />

In VF page, if you do not pass id parameter in URL and using standard controller, Save action creates new record in salesforce. Same way in Lightning data services, you do not need recordId for creating record. 

You need to create a template of record so that it can be used to create new record. It is similar to initializing the sobject to avoid null pointer exception in apex controllers. 

So in doInit function, first create template. Below is an example to create template for account:

doInit: function(component, event, helper) {

// Prepare a new record from template

component.find("accountRecordCreator").getNewRecord(

"Account", // sObject type (entity API name)

null,           // record type (null if no recordtype exist

false,         // skip cache?

$A.getCallback(function() {

var rec = component.get("v.newAccount");  //targetRecord attribute

var error = component.get("v.newAccountError");

if(error || (rec === null)) {

console.log("Error initializing record template: " + error);

}

else {

console.log("Record template initialized: " + rec.sobjectType);

}

})

);

},

In above code "newAccount" and "newAccountError" are component attribute which store information related to Lightning data services.

Now you have created a template and can use newAccount component attribute to specify field values on component. Once user specifies the field values, you can call javascript function on button click to create record. Below is sample code:

createContact: function(component, event, helper) {

component.find("accountRecordCreator").saveRecord(function(saveResult) {

if (saveResult.state === "SUCCESS" || saveResult.state === "DRAFT") {

//record got created in salesforce

//show toast on UI with message

// Reload the view so that all components are refreshed after update

$A.get("e.force:refreshView").fire();

}

else {

var errMsg = 'Unknown problem, state: ' + saveResult.state + ', error: ' + JSON.stringify(saveResult.error);

console.log(errMsg);

alert(errMsg);

}

});

},

If you want to modify any field value in javascript, then set the value in component attribute which hold object information. In our case attribute is "newAccount". So you can set value for "Type" field in Account (as shown below )then call saveRecord method.

component.set("v.newAccount.Type", 'Direct');

• Delete Record 

For delete also, you need to use force:recordPreview tag and need to specify the recordId and in fields specify Id.

<force:recordData aura:id="recordDeleteHandler"

      recordId="{!v.recordId}"

      fields="Id"

      targetError="{!v.recordError}"

      />

In order to delete record on button click, call below mentioned controller function:

DeleteRecord: function(component, event, helper) {

        component.find("recordDeleteHandler").deleteRecord($A.getCallback(function(saveResult) {

            if (saveResult.state === "SUCCESS" || saveResult.state === "DRAFT") {

//record got deleted from salesforce

                // Reload the view so that all components are refreshed after update

                $A.get("e.force:refreshView").fire();

            }

            else {

 var errMsg = 'Unknown problem, state: ' + saveResult.state + ', error: ' + JSON.stringify(saveResult.error);

                console.log(errMsg);

alert(errMsg);

            }

        }));

    }

I have created a component which will will display list of Account by using Apex controller and then I am creating, editing, viewing and deleting records using Lightning Data Services. For all DMl operation on this component, I am not using server-side apex controller and performing these operations using code snippet shown above.

I have created different components as mentioned below:

• AccountListView : This will display 10 Accounts and will use controller method to get list of accounts.
• AccountView : To view account details. We will just pass account recordId to this component.
• AccountEdit  : This will be used to edit or create new record. If we pass recordId to component, then it will update record. If we pass null in recordId then it will create new record.

After saving below code in your org, create App Page from Lightning App Builder section and add "AccountListView" component to it and activate it. After this open this app page and test the functionality.

If your org have recordtypes defined for Account object, then while creating new Account, you will get recordType selection page. No validation have been applied on fields as this is created for demo purpose only.

You can download complete code from below link:
Sample Code utilizing Lightning Data Services

Below is complete Code:

Looking forward for everyone's comments and feedback!!!!!

Changes to Lightning Data Services (LDS) in Summer'17 Release

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