It would be great if I can export Invoice details in JSON format that could be uploaded to GST (India) site.
Is there any way to do it? Any hook in software that is provided to do that?
if you are using cloud or server edition, you can access API.
but it is still under development and not completely functional at present.
I agree with what sharpdrivetek wrote.
The API already outputs in JSON, so you could get details for an individual invoice in this way by accessing the API using your web browser and copy/pasting into a text file.
However, if you wish to put multiple invoices into a single JSON file, you will need to write a program to connect to the API and do this for you - or hire a local IT professional to perform the task.
As sharpdrivetek mentioned, API is available only for Cloud and Server Edition.