Incrementing Value of incoming value in Azure Table Insert - ios

Question

I am an iOS developer & currently working with Azure mobile services SDK in iOS.
In my case, I am providing each user as a uniqueid say 'myid' in Table say 'todomytable'. In todomytable.js file I am performing check for myid value. If coming value of 'myid' from device is less than stored value in table then I am increasing incoming value greater than earlier stored value in table by One. Below is my logic in todomytable.js
table.insert(function (context) {
context.item.userId = context.user.id;
//....
var intIncomingID = context.item.myid; //ID coming from mobile device
//Call back to get max value of 'myid' from Table
var myFunction = function( callback) {
var query = {
sql: 'select MAX(myid) from TodoItem'
};
context.data.execute(query).then(function (results) {
var objectTest = eval(JSON.stringify(results));
var tempObject = objectTest[0];
var previuosIntID = tempObject["MAX(myid)"];
callback(previuosIntID);
});
};
myFunction(function(returnValue) {
console.log("returnValue is : "+returnValue);
if (intIncomingID<=returnValue)
{
console.log('IF');
context.item.userId = context.user.id;
returnValue = returnValue+1;
context.item.myid = returnValue;
console.log("UPDATED value is : "+context.item.myid);
}
else{
context.item.myid = intIncomingID;
console.log("ITEM value is :"+intIncomingID);
}
return context.execute();
});
});
But issue is that table is not getting update & in mobile log I am getting network request time out error as below
{Error Domain=NSURLErrorDomain Code=-1001 "The request timed out."}
Can anyone suggest how to resolve this issue? I have to store 'myid' in incremented order in table. I am new to Node.js, so sorry If I am making any foolish mistake.

Answer 1

It is likely that there is an exception occurring at some point that causes a promise to reject. Given that there is no promise exception handler defined, the exception ends up being "swallowed". Try the following:
var table = module.exports = require('azure-mobile-apps').table()
table.insert(function (context) {
context.item.userId = context.user.id;
var intIncomingID = context.item.myid; //ID coming from mobile device
var query = { sql: 'select MAX(myid) from TodoItem' };
return context.data.execute(query)
.then(function (results) {
var tempObject = results[0];
var previousIntID = tempObject["MAX(myid)"];
console.log("previous ID is : " + previousIntID);
if (intIncomingID <= previousIntID) {
context.item.myid = previousIntID + 1;
console.log("UPDATED value is : " + context.item.myid);
} else {
context.item.myid = intIncomingID;
console.log("ITEM value is :" + intIncomingID);
}
return context.execute();
});
});
Some points to note:
context.data.execute returns a promise - we are returning this from the insert function so that the Mobile Apps runtime handles any rejected promises
context.execute also returns a promise; we are returning this so that the promises are "chained" properly
Hope this helps!