We have a existing Salesforce webservice. This webservice is used by an external application to create a custom object records in Salesforce.
As part of the webservice API call, we have a datetime field which gets updated in Salesforce.
Salesforce requires the incoming date time in GMT format and then it converts to Integration user time zone in Salesforce. So the external application converts the Date time to GMT before sending to Salesforce. They are doing this conversion by adding 4 hrs to date time and send it to Salesforce.
The external application is currently in EDT, when they switch to EST after daylight savings period ends, then their current conversion to GMT will fail. (after day light saving ends; GMT= EST+5)
The external application is not very robust with date time functions and they have very limited capability and also they cannot send the time zone details when calling the Salesforce webservice.
Given these limitations of external application
- How to dynamically convert the date time to GMT when the external application clock switches from Daylight savings to standard time. (they do not send us the time zone ;they follow the standard clock switch of EDT to EST & vice versa)
Things that does not change on the external application are:
- They are always on Eastern time zone
- Exteral ApplicationClock automatically switch from EDT to EST and vice versa
- They will start sending the Date time 'AS-IS' based on the current time zone on the system.