Re: backup manifests - Mailing list pgsql-hackers

From David Steele
Subject Re: backup manifests
Date
Msg-id 1115c3d4-2d80-8388-4fd4-5fdb3ee9b429@pgmasters.net
Whole thread Raw
In response to Re: backup manifests  (Stephen Frost <sfrost@snowman.net>)
Responses Re: backup manifests  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Hi Stephen,

On 1/14/20 1:35 PM, Stephen Frost wrote:
> 
> My thought, which I had expressed to David (though he obviously didn't
> entirely agree with me since he suggested the other options), was to
> adapt the pgBackRest JSON parser, which isn't really all that much code.

It's not that I didn't agree, it's just that the pgBackRest code does 
use mem contexts, the type system, etc.  After looking at some other 
solutions with similar amounts of code I thought they might be more 
acceptable.  At least it seemed like a good idea to throw it out there.

> Even so, David's offered to adjust the code to use the frontend's memory
> management (*cough* malloc()..), and error handling/logging, and he had
> some idea for Variadics (or maybe just pulling the backend's Datum
> system in..?  He could answer better), and basically write a frontend
> JSON parser for PG without too much code, no external dependencies, and
> to make sure it answers this requirement, and I've agreed that he can
> spend some time on that instead of pgBackRest to get us through this, if
> everyone else is agreeable to the idea.  

To keep it simple I think we are left with callbacks or a somewhat 
static "what's the next datum" kind of approach.  I think the latter 
could get us through a release or two while we make improvements.

> Obviously this isn't intended
> to box anyone in- if there turns out even after the code's been written
> to be some fatal issue with using it, so be it, but we're offering to
> help.

I'm happy to work up a prototype unless the consensus is that we 
absolutely don't want a second JSON parser in core.

Regards,
-- 
-David
david@pgmasters.net



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