How to get more than one SharePoint list using REST API?

Question

I have created multiple lists in SharePoint 2013. I need to get the multiple list items using REST API call.

I have tried the method to get the multiple list items using API within the for loop but it works slowly.

Please suggest best idea to get multiple lists response.

Answer 1

To get data from multiple list at a same time, we need to parallel Ajax get request for getting data from more than one list.

Let's take one example:

We have two list named "List1" and "List2" and we need to get all items from both lists.

We create one module for get item:

var getModule = (function () {
    var baseRequest = {
        url: "",
        type: ""
    };

    var getApp = {
    };
    var getApp = {
        getRequest: getRequest,
    };

    function getRequest(endpoint, _async) {
        //var dfd = $.Deferred();
        var request = baseRequest;
        request.type = "GET";
        request.url = endpoint;
        request.headers = {
            ACCEPT: "application/json;odata=verbose",
            "X-RequestDigest": $("#__REQUESTDIGEST").val()

        };
        return $.ajax(request);
        //return dfd.promise();
    };

    return getApp;
})();

After that we used jQuery $.when function for getting data from multiple list as shown below

var list1FilesInfo = $.Deferred();
var list2FilesInfo = $.Deferred();

        var dfdList1Files;
        var dfdList2Files;

        var list1URL = "Your Web URL" + "/_api/Web/lists/getbytitle('List1')/items";
        var list2URL = "Your Web URL" + "/_api/Web/lists/getbytitle('List2')/items"



        dfdList1Files = getModule.getRequest(list1URL, true);
        dfdList2Files = getModule.getRequest(list2URL, true);

        dfdList1Files.done(function (data) {
            list1FilesInfo.resolve(data);
        });
        dfdList2Files.done(function (ldata) {
            list2FilesInfo.resolve(ldata);
        });

        $.when(list1FilesInfo, list2FilesInfo).then(function (list1Data, list2Data) {
            conssole.log('success');
        });

Hope it works for you.