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Change the cells of a table in an interval time using OData model

I have this code and I need my table to show the first 10 patients and, after 10 seconds, show the next 10 without touching any button (automatically).
I'm looking for something similar to this: https://embed.plnkr.co/ioh85m5OtPmcvPHyl3Bg/
But with an OData model (as specified on my view and controller).
This is my view:
<Table id="tablaPacientes" items="{/EspCoSet}">
<columns>
<!-- ... -->
</columns>
<ColumnListItem>
<ObjectIdentifier title="{Bett}" />
<!-- ... -->
</ColumnListItem>
</Table>
This is my controller:
onInit: function () {
var oModel = this.getOwnerComponent().getModel("zctv");
this.getView().setModel(oModel);
},
onBeforeRendering: function () { // method to get the local IP because I need it for the OData
var ipAddress;
var RTCPeerConnection = window.webkitRTCPeerConnection || window.mozRTCPeerConnection;
var self = this;
function grepSDP (sdp) {
var ip = /(192\.168\.(0|\d{0,3})\.(0|\d{0,3}))/i;
sdp.split('\r\n').forEach(function (line) {
if (line.match(ip)) {
ipAddress = line.match(ip)[0];
self.setIp(ipAddress);
}
});
}
if (RTCPeerConnection) {
(function () {
var rtc = new RTCPeerConnection({
iceServers: []
});
rtc.createDataChannel('', {
reliable: false
});
rtc.onicecandidate = function (evt) {
if (evt.candidate) {
grepSDP(evt.candidate.candidate);
}
};
rtc.createOffer(function (offerDesc) {
rtc.setLocalDescription(offerDesc);
}, function (e) {
console.log("Failed to get Ip address");
});
})();
}
},
setIp: function (ip) {
this.getView().byId("planta").bindElement({
path: "/CenTVSet('" + ip + "')"
});
var oModel = this.getView().getModel();
var that = this;
oModel.read("/CenTVSet('" + ip + "')", {
success: function (oData, oRes) {
var einri = oData.Einri;
var orgpf = oData.Orgpf;
var oTable = that.getView().byId("tablaPacientes");
var oBinding = oTable.getBinding("items");
var aFilters = [];
var filterO = new Filter("Orgna", sap.ui.model.FilterOperator.EQ, orgpf);
aFilters.push(filterO);
var filterE = new Filter("Einri", sap.ui.model.FilterOperator.EQ, einri);
aFilters.push(filterE);
oBinding.filter(aFilters);
}
});
}
I searched some functions like IntervalTrigger but I really don't know how can I use it for this example.

Here are some small samples:
OData V4: https://embed.plnkr.co/4zIAH7q2E0lngbyX
OData V2: https://embed.plnkr.co/rNa0TktXiQqSCGJV
startList: function(listBase, $skip, $top, restInfo) {
let startIndex = $skip;
let length = $top;
let totalSize;
(function repeat(that) {
const bindingInfo = Object.assign({ startIndex, length }, restInfo);
listBase.bindItems(bindingInfo);
listBase.data("repeater", event => {
totalSize = event.getParameter("total"); // $count value
startIndex += $top;
startIndex = startIndex < totalSize ? startIndex : 0;
setTimeout(() => repeat(that), 2000);
}).attachEventOnce("updateFinished", listBase.data("repeater"), that);
})(this);
},
stopList: function(listBase) {
listBase.detachEvent("updateFinished", listBase.data("repeater"), this);
},
The samples make use of startIndex and length in the list binding info which translates to $skip and $top system queries of the entity request URL. I.e. appending those system queries to the request URL (e.g. https://<host>/<service>/<EntitySet>?$skip=3&$top=3), should return the correct set of entities like this.
Additional options for the list binding info can be found in the UI5 documentation as I explained here.
JavaScript part
The interval is implemented with an IIFE (Immediately Invoked Function Expression) in combination with setTimeout instead of setInterval.
setInterval has the following disadvantages:
The callback is not immediately invoked. You'd have to wait 10 seconds first to trigger the 1st callback.
Does not wait for the data response to arrive. This may cause skipping a batch or showing it for a too short period of time because the delay simply continues regardless of the server response.
setTimeout instead offers a better control when the next batch should be requested.

You could bind you items using bindItems, pass skip,top parameters and wrap the whole thing in a setInterval
var iSkip = 0;
var iTop = 10;
setInterval(function() {
table.bindItems("/EspCoSet", {
urlParameters: {
"$skip": iSkip.toString() // Get first 10 entries
"$top": iTop.toString()
},
success: fuction (oData) {
iSkip = iTop; // Update iSkip and iTop to get the next set
iTop+= 10;
}
...
}, 10000); // Each 10 seconds
)
Almost the same thing, just use oModel.read to read the entities into you viewModel.allEntities, bind your table to the viewModel.shownEntities and use a setInterval to get the next 10 from allEntities to update shownEntities.

Get specifics ids in IndexedDB [duplicate]

I want to execute this query
select * from properties where propertyCode IN ("field1", "field2", "field3")
How can I achieve this in IndexedDB
I tried this thing
getData : function (indexName, params, objectStoreName) {
var defer = $q.defer(),
db, transaction, index, cursorRequest, request, objectStore, resultSet, dataList = [];
request = indexedDB.open('test');
request.onsuccess = function (event) {
db = request.result;
transaction = db.transaction(objectStoreName);
objectStore = transaction.objectStore(objectStoreName);
index = objectStore.index(indexName);
cursorRequest = index.openCursor(IDBKeyRange.only(params));
cursorRequest.onsuccess = function () {
resultSet = cursorRequest.result;
if(resultSet){
dataList.push(resultSet.value);
resultSet.continue();
}
else{
console.log(dataList);
defer.resolve(dataList);
}
};
cursorRequest.onerror = function (event) {
console.log('Error while opening cursor');
}
}
request.onerror = function (event) {
console.log('Not able to get access to DB in executeQuery');
}
return defer.promise;
But didn't worked. I tried google but couldn't find exact answer.

If you consider that IN is essentially equivalent to field1 == propertyCode OR field2 == propertyCode, then you could say that IN is just another way of using OR.
IndexedDB cannot do OR (unions) from a single request.
Generally, your only recourse is to do separate requests, then merge them in memory. Generally, this will not have great performance. If you are dealing with a lot of objects, you might want to consider giving up altogether on this approach and thinking of how to avoid such an approach.
Another approach is to iterate over all objects in memory, and then filter those that don't meet your conditions. Again, terrible performance.
Here is a gimmicky hack that might give you decent performance, but it requires some extra work and a tiny bit of storage overhead:
Store an extra field in your objects. For example, plan to use a property named hasPropertyCodeX.
Whenever any of the 3 properties are true (has the right code), set the field (as in, just make it a property of the object, its value is irrelevant).
When none of the 3 properties are true, delete the property from the object.
Whenever the object is modified, update the derived property (set or unset it as appropriate).
Create an index on this derived property in indexedDB.
Open a cursor over the index. Only objects with a property present will appear in the cursor results.
Example for 3rd approach
var request = indexedDB.open(...);
request.onupgradeneeded = upgrade;
function upgrade(event) {
var db = event.target.result;
var store = db.createObjectStore('store', ...);
// Create another index for the special property
var index = store.createIndex('hasPropCodeX', 'hasPropCodeX');
}
function putThing(db, thing) {
// Before storing the thing, secretly update the hasPropCodeX value
// which is derived from the thing's other properties
if(thing.field1 === 'propCode' || thing.field2 === 'propCode' ||
thing.field3 === 'propCode') {
thing.hasPropCodeX = 1;
} else {
delete thing.hasPropCodeX;
}
var tx = db.transaction('store', 'readwrite');
var store = tx.objectStore('store');
store.put(thing);
}
function getThingsWherePropCodeXInAnyof3Fields(db, callback) {
var things = [];
var tx = db.transaction('store');
var store = tx.objectStore('store');
var index = store.index('hasPropCodeX');
var request = index.openCursor();
request.onsuccess = function(event) {
var cursor = event.target.result;
if(cursor) {
var thing = cursor.value;
things.push(thing);
cursor.continue();
} else {
callback(things);
}
};
request.onerror = function(event) {
console.error(event.target.error);
callback(things);
};
}
// Now that you have an api, here is some example calling code
// Not bothering to promisify it
function getData() {
var request = indexedDB.open(...);
request.onsuccess = function(event) {
var db = event.target.result;
getThingsWherePropCodeXInAnyof3Fields(db, function(things) {
console.log('Got %s things', things.length);
for(let thing of things) {
console.log('Thing', thing);
}
});
};
}

Use of indexedDB returns 'undefined'

I'm trying to use indexedDB.
Some parts of my code works.
In the following example, the first function adds server in my DB, however in Chrome debug console there is an undefined message not related to any line. The server is already added though.
The second function puts records in an array, there is also an undefined message not related to any line.
If I do a console.log(servers); just before return servers; I can see the array content, however if I call the function somewhere else in my code, the returned object is undefined.
var dbName = 'myDBname',
dbServersStoreName = 'servers',
dbVersion = 1,
openDBforCreation = indexedDB.open(dbName, dbVersion);
openDBforCreation.onupgradeneeded = function(e) {
var db = e.target.result;
var objStore = db.createObjectStore(dbServersStoreName, { keyPath: "alias"
});
var index = objStore.createIndex("serversAlias", ["alias"]);
};
function addServerInDB(serverAlias,serverAddress,user,pwd){
var myDB = indexedDB.open(dbName, dbVersion);
myDB.onerror = function() {
var notification = document.querySelector('.mdl-js-snackbar');
notification.MaterialSnackbar.showSnackbar(
{message: 'Error while trying to access internal database'});
}
myDB.onsuccess = function(e) {
var db = e.target.result,
request = db.transaction([dbServersStoreName],
"readwrite").objectStore("servers")
.put({alias:''+serverAlias+'',
address:''+serverAddress+'', login:''+user+'',
passwd:''+pwd+''});
request.onsuccess = function(){
var notification = document.querySelector('.mdl-js-snackbar');
notification.MaterialSnackbar.showSnackbar(
{message: 'Server added'});
}
}
};
function listServersInDB(){
var myDB= indexedDB.open(dbName, dbVersion);
myDB.onerror = function() {
var notification = document.querySelector('.mdl-js-snackbar');
notification.MaterialSnackbar.showSnackbar(
{message: 'Error while trying to access internal database'});
}
myDB.onsuccess = function(e) {
var servers = new Array(),
db = e.target.result,
request = db.transaction(["servers"], "readwrite")
.objectStore("servers")
.openCursor();
request.onsuccess = function(e){
var cursor = e.target.result;
if(cursor){
servers.push(cursor.value);
cursor.continue();
}
return servers;
}
}
};
I do not understand where this undefined comes from and if that is why the listServersInDB() function doesn't work.

You need to learn more about how to write asynchronous Javascript. There are too many errors in your code to even begin reasoning about the problem.
Briefly, don't do this:
function open() {
var openDatabaseRequest = ...;
}
openDatabaseRequest.foo = ...;
Instead, do this:
function open() {
var openDatabaseRequest = ...;
openDatabaseRequest.foo = ...;
}
Next, you don't need to try and open the same database multiple times. Why are you calling indexedDB.open twice? You can open a database to both install it and to start using it immediately. All using the same connection.
Next, I'd advise you don't name the database open request as 'myDB'. This is misleading. This is an IDBRequest object, and more specifically, an IDBOpenRequest object. A request isn't a database.
Next, you cannot return the servers array from the request.onsuccess at the end. For one this returns to nowhere and might be source of undefined. Two this returns every single time the cursor is advanced, so it makes no sense at all to return return servers multiple times. Three is that this returns too early, because it cannot return until all servers enumerated. To properly return you need to wait until all servers listed. This means using an asynchronous code pattern. For example, here is how you would do it with a callback:
function listServers(db, callbackFunction) {
var servers = [];
var tx = db.transaction(...);
var store = tx.objectStore(...);
var request = store.openCursor();
request.onsuccess = function() {
var cursor = request.result;
if(cursor) {
servers.push(cursor.value);
cursor.continue();
}
};
tx.oncomplete = function() {
callbackFunction(servers);
};
return 'Requested servers to be loaded ... eventually callback will happen';
}
function connectAndList() {
var request = indexedDB.open(...);
request.onsuccess = function() {
var db = request.result;
listServers(db, onServersListed);
};
}
function onServersListed(servers) {
console.log('Loaded servers array from db:', servers);
}
When you call a function that does not return a value, it returns undefined. All functions in JavaScript return undefined unless you explicitly return something else.
When you call a function from the devtools console, and that function returns undefined, then the console prints out '-> undefined'. This is an ordinary aspect of using the console.
If you want to get a function that returns the list of servers as an array, well, you cannot. The only way to do that in a pretend sort of way, is to use an 'async' function, together with promises.
async function getServers() {
var db = await new Promise(resolve => {
var request = indexedDB.open(...);
request.onsuccess = () => resolve(request.result);
});
var servers = await new Promise(resolve => {
var tx = db.transaction(...);
var request = tx.objectStore(...).getAll();
request.onsuccess = () => resolve(request.result);
});
return servers;
}
One more edit, if you want to call this from the console, use await getServers();. If you do not use the top-level await in console, then you will get the typical return value of async function which is a Promise object. To turn a promise into its return value you must await it.

Clear and helpfull explanations, Thank you.
I open database multiple times beacause the first time is for checking if DB needs an upgrade and doing something if needed. I'll add 'db.close()' in each functions.
Then, I tried your exemple and the result is the same:
console.log('Loaded servers array from db:', servers); works
but return servers; Don't work.
And in console there is already an undefined without related line :
Screenshot

Javascript global array undefined when in OnSuccess function of PageMethod?

I have multiple user controls loading asynchronously on my page, using pagemethods. Some dropdownlists cause asynchronous callbacks of those usercontrols, and the user controls are reloaded with modified content. We had our reasons for doing it this way.
However, currently our users have to wait for those user controls to load before they can change their selection in the dropdownlists. In an attempt to provide a better user experience, I'm attempting to abort previous, yet-to-be-loaded, requests.
I'm attempting to maintain a global js array of outstanding asynchronous request executors, in order to ensure that only the latest request for each user control is loaded. In other words, I want to cancel previous requests for a specific usercontrol which have yet to load and give priority to the latest request for that usercontrol.
The problem I have is that by the time execution of my OnSuccess function happens, the global array is undefined.
Am I going about this in the wrong way? What is it that I don't know?
Any help would be much appreciated.
This is a pared down example of my code:
var outstanding_requests;
$.fn.remove_or_item = function (val, col) {
var arr1 = $(this);
var arr2 = new Array();
$.each(arr1, function (k, v) {
if (v[col] != val) { arr2.push(v); }
else if (v[1].get_started()) { v[1].abort(); }
});
return arr2;
}
$.fn.find_or_item = function (val, col) {
var item;
var arr1 = $(this);
$.each(arr1, function (k, v) {
if (v[col] == val) { item = v; return false; } return true;
});
return item;
}
function RunMyPageMethod(panelname) {
var request; //current request object
if (outstanding_requests == undefined) { outstanding_requests = new Array(); }
outstanding_requests = $(outstanding_requests).remove_or_item(panelname, 0);
request = PageMethods._staticInstance.LoadUserControl(panelname, PageMethodSuccess, PageMethodFailure);
outstanding_requests.push([panelname, request.get_executor()]);
}
function PageMethodSuccess(result, userContext, methodName) {
var panelname = result.split("|")[0];
//here outstanding_requests is undefined
if($(outstanding_requests).find_or_item(panelname,0))
{
outstanding_requests = $(outstanding_requests).remove_or_item(panelname, 0);
//load usercontrol
}
}

Arrays are pass by reference in js. This has the benefit of allowing me to see the array in the state it was in when I hit the OnSuccess function, not the state it was in when I called the pagemethod. At least I think that's why it works. I needed the reference to the array passed into the OnSuccess function. I ended up doing this with the last two functions shown above, which worked nicely..
function RunMyPageMethod(panelname) {
var request; //current request object
if (outstanding_requests == undefined) { outstanding_requests = new Array(); }
outstanding_requests = $(outstanding_requests).remove_or_item(panelname, 0);
request = PageMethods._staticInstance.LoadUserControl(panelname,function(result,userContext,methodName){ PageMethodSuccess(result,userContext,methodName,outstanding_requests); }, PageMethodFailure);
outstanding_requests.push([panelname, request.get_executor()]);
}
function PageMethodSuccess(result, userContext, methodName, outstanding_requests) {
var panelname = result.split("|")[0];
if($(outstanding_requests).find_or_item(panelname,0))
{
outstanding_requests = $(outstanding_requests).remove_or_item(panelname, 0);
//load usercontrol
}
}

How to make a Firefox addon listen to xmlhttprequests from a page?

Background
I have an existing extension designed to accompany a browser-based game (The extension is mine, the game is not). The extension had been scraping the pages as they came in for the data it needed and making ajax requests for taking any actions.
Problem
The game developers recently changed a number of actions on the site to use ajax requests and I am thus far unable to get the data from those requests.
What I have so far
function TracingListener() {
}
TracingListener.prototype =
{
originalListener: null,
receivedData: [], // array for incoming data.
onDataAvailable: function(request, context, inputStream, offset, count)
{
var binaryInputStream = CCIN("#mozilla.org/binaryinputstream;1",
"nsIBinaryInputStream");
var storageStream = CCIN("#mozilla.org/storagestream;1", "nsIStorageStream");
binaryInputStream.setInputStream(inputStream);
storageStream.init(8192, count, null);
var binaryOutputStream = CCIN("#mozilla.org/binaryoutputstream;1",
"nsIBinaryOutputStream");
binaryOutputStream.setOutputStream(storageStream.getOutputStream(0));
// Copy received data as they come.
var data = binaryInputStream.readBytes(count);
this.receivedData.push(data);
binaryOutputStream.writeBytes(data, count);
this.originalListener.onDataAvailable(request, context,storageStream.newInputStream(0), offset, count);
},
onStartRequest: function(request, context) {
this.originalListener.onStartRequest(request, context);
},
onStopRequest: function(request, context, statusCode)
{
try {
if (request.originalURI && piratequesting.baseURL == request.originalURI.prePath && request.originalURI.path.indexOf("/index.php?ajax=") == 0) {
dump("\nProcessing: " + request.originalURI.spec + "\n");
var date = request.getResponseHeader("Date");
var responseSource = this.receivedData.join();
dump("\nResponse: " + responseSource + "\n");
piratequesting.ProcessRawResponse(request.originalURI.spec, responseSource, date);
}
} catch(e) { dumpError(e);}
this.originalListener.onStopRequest(request, context, statusCode);
},
QueryInterface: function (aIID) {
if (aIID.equals(Ci.nsIStreamListener) ||
aIID.equals(Ci.nsISupports)) {
return this;
}
throw Components.results.NS_NOINTERFACE;
}
}
hRO = {
observe: function(aSubject, aTopic, aData){
try {
if (aTopic == "http-on-examine-response") {
if (aSubject.originalURI && piratequesting.baseURL == aSubject.originalURI.prePath && aSubject.originalURI.path.indexOf("/index.php?ajax=") == 0) {
var newListener = new TracingListener();
aSubject.QueryInterface(Ci.nsITraceableChannel);
newListener.originalListener = aSubject.setNewListener(newListener);
dump("\n\nObserver Processing: " + aSubject.originalURI.spec + "\n");
for (var i in aSubject) {
dump("\n\trequest." + i);
}
}
}
} catch (e) {
dumpError(e);
}
},
QueryInterface: function(aIID){
if (aIID.equals(Ci.nsIObserver) ||
aIID.equals(Ci.nsISupports)) {
return this;
}
throw Components.results.NS_NOINTERFACE;
}
};
var observerService = Cc["#mozilla.org/observer-service;1"] .getService(Ci.nsIObserverService);
observerService.addObserver(hRO, "http-on-examine-response", false);
What's happening
The above code is notified properly when an http request is processed. The uri is also available and is correct (it passes the domain/path check) but the responseSource that gets dumped is, as far as I can tell, always the contents of the first http request made after the browser opened and, obviously, not what I was expecting.
The code above comes in large part from http://www.softwareishard.com/blog/firebug/nsitraceablechannel-intercept-http-traffic/. I'm really hoping that it's just something small that I've overlooked but I've been banging my head against the desk for days on this one, and so now I turn to the wisdom of SO. Any ideas?

but the responseSource that gets
dumped is, as far as I can tell,
always the contents of the first http
request made after the browser opened
and, obviously, not what I was
expecting.
There is a problem with the code above. The "receivedData" member is declared on prototype object and have empty array assigned. This leads to every instantiation of the TracingListener class to be using the same object in memory for receivedData. Changing your code to might solve he problem:
function TracingListener() {
this.receivedData = [];
}
TracingListener.prototype =
{
originalListener: null,
receivedData: null, // array for incoming data.
/* skipped */
}
Not sure though if this will solve your original problem.