SugarCRM REST API Session expires frequently - rest

Question

I use REST API in JavaScript. When I request REST API multiple times, it returns(response) invalid session id, but I am providing a valid session id, because I have pulled data with this session id.
Anyone came across this issue?
function sugarLogin(url, user, password) {
var request = new XMLHttpRequest();
var params = {
user_auth: {
user_name: user,
password: password
},
name_value_list: [{
name: 'notifyonsave',
value: 'true'
}]
};
var json = $.toJSON(params);
var crm_api = url;
request.open("POST", crm_api, true);
request.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
request.onreadystatechange = function () {
if (request.readyState == 4 && request.status == 200) {
var response = request.responseText;
var response_obj = jQuery.parseJSON(response);
if (response_obj) {
if (response_obj.name && response_obj.name == "Invalid Login") {
//invalid login
ProcessingFlag = 3;
} else {
session_id = response_obj.id;
ProcessingFlag = 1;
}
}
} else if (request.readyState == 4 && request.status == 404) {
ProcessingFlag = 2;
}
}
request.send("method=login&input_type=JSON&response_type=JSON&rest_data=" + json);}
I have used above code to login and set session_id (global scope)
and then using this session id I am calling search_by_module function of REST API.
It is working fine but if made multiple requests frequently then it says invalid session id.
Although I have tried to call login function again before making search_by_module call.
Main issue is when I tried calling other REST function after response returned from search_by_module and rendered HTML, it says me invalid session. I can't figure out why session expires immediately while we know that on server session expires after 24 minutes (server where our sugar instance hosted)

Answer 1

I bet you're getting this because of item number 3 :
1/ Defined an error callback that checks for that particular response -invalid login- and calls the login function. Reading your code, I guess this is ProcessingFlag = 3; job.
2/ make sure the login function updates the session_id correctly and globally so that future function calls will get the correct value.
3/ make sure you're passing that new session_id to all your subsequent calls as FIRST parameter in all you rest_data. I got caught on this and lost many hours only to find out that SugarCRM DOESN'T support named parameters in its rest_data (is it poorely implemented function-arguments-wise ?) This is because I was adding session_id as last parameter and all of my REST calls were returning invalid ID.