Need separate context per user about plv8 HOT 5 CLOSED

Agree. With your proposal, "this" is going to be private to the function?

I implemented the code to support separate context.  In turn, my code is for 
per function, not per user.  The feature is experimental and need to set guc 
plv8.use_separate_context to on (default to off,) as the performance overhead 
is sometimes too big.

I don't think this is the way to go, for several reasons. 

First, it's unlike what is done in other languages, and I think orthogonality 
would be good. 

Second, it should not be controlled by a GUC. This is a security issue, and we 
should not have a mode where information can leak across roles changes. What we 
should have is a hash of contexts keyed by role id, and switch to the correct 
context for the current role, if necessary creating it first. That will also 
have the side effect that globally saved data per role will simply be visible 
as one would expect.

My proposed startup functionality would be run in each context as it's created 
- in the vast majority of cases that would only be once per backend.

I was intending to work on this, and can undertake it if the design above is 
agreed.

The current GUC is for only trial purpose, and I don't intend to expose it as a 
normal option.  I agree my approach was wrong and should do it your way.  
However, I have another idea around it with the global namespace issue and 
yield function implementation, so you can of course work on it but I'd like to 
see your patch before commit.  Possibly my idea is unrelated topic here, but 
still I'm interested.

I think this is done.