Delta Tracking for Offline Mobile Hybrid Application (Cloud Build)

[kunju1991]

Hi All,

I have created an offline Mobile Hybrid application using the cloud build (packaged app) option in the WebIDE full stack. The offline functionality is working fine i can perform all the CRUD operations from the application.

Now i want to enable delta tracking for performance improvement in my application. For the same i have enabled delta tracking for backend OData service i.e. now i am getting the delta token <linkrel="delta"href="EmployeeSet?!deltatoken='005056A254D81ED996D4F09BA85E8104_20190409091200'"/>)

Based on some of the blogs i got the understanding that we don't need to do any code level changes in the application, hence my code is untouched. Please find the custom code that i added in the file mobile>hybrid>sap-mobile-hybrid.js below:

openStore: function () {
	sap.m.MessageToast.show("In openStore");
	jQuery.sap.require("sap.ui.thirdparty.datajs"); //Required when using SAPUI5 and the Kapsel Offline Store
	var properties = {
		"name": "chek_mainService",
		"host": sap.hybrid.kapsel.appContext.registrationContext.serverHost,
		"port": sap.hybrid.kapsel.appContext.registrationContext.serverPort,
		"https": sap.hybrid.kapsel.appContext.registrationContext.https,
		"serviceRoot": fiori_client_appConfig.appID + "_" + mobile_appRoutes[0].destination,

			"definingRequests": {
				"chekset": "/parentSet",
				"empset": "/EmployeeSet"
			}
		};


		store = sap.OData.createOfflineStore(properties);


		var openStoreSuccessCallback = function () {
			sap.m.MessageToast.show("In openStoreSuccessCallback");
			sap.OData.applyHttpClient(); //Offline OData calls can now be made against datajs.
			sap.hybrid.startApp();
		}


		var openStoreErrorCallback = function (error) {
			sap.m.MessageToast.show("In openStoreErrorCallback");
			sap.m.MessageToast.show("An error occurred" + JSON.stringify(error));
		}


		store.open(openStoreSuccessCallback, openStoreErrorCallback);
	},


	refreshStore: function () {
		sap.m.MessageToast.show("Offline events: refreshStore");
		if (!store) {
			sap.m.MessageToast.show("The store must be open before it can be refreshed");
			return;
		}
		store.refresh(sap.hybrid.refreshStoreCallback, sap.hybrid.errorCallback, null, sap.hybrid.progressCallback);
	},


	refreshStoreCallback: function () {
		sap.m.MessageToast.show("Offline events: refreshStoreCallback");
	},


	clearStore: function () {
		sap.m.MessageToast.show("Offline events: clearStore");
		store.close(sap.hybrid.closeStoreCallback, sap.hybrid.errorCallback);
	},


	closeStoreCallback: function () {
		sap.m.MessageToast.show("Offline events: closeStoreCallback");
		store.clear(function () {
			sap.m.MessageToast.show("Clear Success");
		}, sap.hybrid.errorCallback);
	},


	flushStore: function () {
		sap.m.MessageToast.show("Offline events: flushStore");
		if (!store) {
			sap.m.MessageToast.show("The store must be open before it can be flushed");
			return;
		}
		store.flush(sap.hybrid.flushStoreCallback, sap.hybrid.errorCallback, null, sap.hybrid.progressCallback);
	},


	flushStoreCallback: function () {
		sap.m.MessageToast.show("Offline events: flushStoreCallback");
	},


	errorCallback: function (error) {
		sap.m.MessageToast.show("Offline events: errorCallback");
		sap.m.MessageToast.show("An error occurred: " + JSON.stringify(error));
	},


	progressCallback: function (progressStatus) {
		// sap.m.MessageToast.show("Offline events: progressCallback");


		var status = progressStatus.progressState;
		var lead = "unknown";
		if (status === sap.OfflineStore.ProgressState.STORE_DOWNLOADING) {
			lead = "Downloading ";
		} else if (status === sap.OfflineStore.ProgressState.REFRESH) {
			lead = "Refreshing ";
		} else if (status === sap.OfflineStore.ProgressState.FLUSH_REQUEST_QUEUE) {
			lead = "Flushing ";
		} else if (status === sap.OfflineStore.ProgressState.DONE) {
			lead = "Complete ";
		} else {
			sap.m.MessageToast.show("Unknown status in progressCallback");
		}
		sap.m.MessageToast.show(lead + "Sent: " + progressStatus.bytesSent + "  Received: " + progressStatus.bytesRecv + "   File Size: " +
			progressStatus.fileSize);
	},


	appLogon: function (appConfig) {
		var context = {};
		var url = appConfig.fioriURL;
		if (url && (url.indexOf("https://") === 0 || url.indexOf("http://") === 0)) {
			if (url.indexOf("https://") === 0) {
				context.https = true;
				url = url.substring("https://".length);
			} else {
				context.https = false;
				url = url.substring("http://".length);
			}


			if (url.indexOf("?") >= 0) {
				url = url.substring(0, url.indexOf("?"));
			}
			if (url.indexOf("/") >= 0) {
				url = url.split("/")[0];
			}
			if (url.indexOf(":") >= 0) {
				context.serverHost = url.split(":")[0];
				context.serverPort = url.split(":")[1];
			}
		}


		// set auth element
		if (appConfig.auth) {
			context.auth = appConfig.auth;
		}


		// If communicatorId is set then use it to be compatible with existing values. Otherwise, use the default "REST". 
		// By doing so logon core does not need to send ping request to server root URL, which will cause authentication issue. 
		// It occurs when the root URL uses a different auth method from the application's endpoint URL, as application can only handle authentication on its own endpoint URL.
		context.communicatorId = appConfig.communicatorId ? appConfig.communicatorId : "REST";


		// if ("serverHost" in context && "serverPort" in context && "https" in context) {
		// 	// start SCPms logon
		// 	sap.hybrid.kapsel.doLogonInit(context, appConfig.appID, sap.hybrid.startApp);
		if ('serverHost' in context && 'serverPort' in context && 'https' in context) {
			// start SCPms logon
			sap.hybrid.kapsel.doLogonInit(context, appConfig.appID, sap.hybrid.openStore);
			// Modification of the datasource uri in the manifest file is no longer required. You can use 
		} else {
			console.error("context data for logon are not complete");
		}
	},

In SAP Cloud Platform Mobile Services for the offline plugin of the application in the configuration tab i have made the below configuration.

But still when i check using the Analytics>Network Traces in SCPms, i can see that the service calls are getting the entire data set and not just the delta.

Please tell me how to fix this issue and implement delta tracking in my application.

Thanks,

Kunj Bihari Shukla

[vicenteveiga]

Hi,
I have the same question. Did you find any solution?