Using `SP.ClientContext` vs REST APIs in JavaScript

Question

We are currently building an application and we have to create/update/fetch items in SharePoint lists. We are currently using REST APIs for just about every functionality. But now we need to update multiple items.

I know we can use $.when to batch multiple request and perform (sort of) batch operations with multiple requests to server. But with SP.ClientContext I will have only one request to server. My estimate for number of items to update will be ~50.

As SharePoint does not support batch updates via REST APIs I need to know what will be a good approach to perform multiple update operations - SP.ClientContext OR REST APIs.

Answer 1

JSOM/CSOM supports batching which is the main highlight of its implementation. You can create/update/delete 50 items in one ExecuteQueryAsync call.

function updateListItems() {
var itemArray = [];
var clientContext = SP.ClientContext.get_current();
var oList = clientContext.get_web().get_lists().getByTitle('TestList');


for(var i = 1; i<= 5; i++){    
  var oListItem = oList.getItemById(i);  
  oListItem.set_item('Title', 'My Updated Item!' + i);  
   oListItem.update();
   itemArray[i] = oListItem;
   clientContext.load(itemArray[i]);
}
clientContext.executeQueryAsync(onQuerySucceeded, onQueryFailed);


}
function onQuerySucceeded() {
 alert('Items Updated');
}
function onQueryFailed(sender, args) {
alert('Request failed. ' + args.get_message() + '\n' + args.get_stackTrace());
}

updateListItems();

References

Batch Operations JSOM

JSOM Batching Reference

REST OData v4.0 now Supports batching

You can use $batch query option in REST, to implement batch operations.

REST Batching Reference 1

REST Batching Reference 2

SP 2013 Batch REST