How to access JIRA Server JSESSIONID in my javascript

[Testuser User]

JIRA version 7.13

I want to access  JIRA JSESSIONID in my javascript 

in other way 

I wants to share JIRA session with my webchat
for that i needs to access the JSESSIONID from cookies but i am not getting it(as its http only)
So can you help me out to share JIRA web session with my application

[Testuser User]

does anybody knows this?