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Message-ID: <f91d116f-2f94-4e74-9ea8-b8cc4792bd86@aklaver.com>
Date: Sun, 16 Nov 2025 09:30:59 -0800
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Subject: Re: Overriding default adapters in psycopg
To: Christophe Pettus <xof@thebuild.com>, psycopg@lists.postgresql.org
References: <FA57033D-66AE-42E9-8C5E-968CF69DB893@thebuild.com>
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From: Adrian Klaver <adrian.klaver@aklaver.com>
In-Reply-To: <FA57033D-66AE-42E9-8C5E-968CF69DB893@thebuild.com>
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On 11/16/25 08:56, Christophe Pettus wrote:
> Hi!
> 
> I am attempting to override the default adapters for JSON and JSONB in psycopg (3), but I am not quite sure how to go about it (I'm testing using orjson for serialization and deserialization).  This doesn't appear to work:
> 

>> class CyanJSONBDumper(Dumper):
>>      def dump(self, obj):
>>          return orjson.dumps(obj)
>>
>> psycopg.adapters.register_dumper("jsonb", CyanJSONBDumper)

Following:

https://www.psycopg.org/psycopg3/docs/api/abc.html#psycopg.abc.Dumper.dump

I believe it should be something like:

psycopg.adapters.register_dumper(<some_python_object>, CyanJSONBDumper)


-- 
Adrian Klaver
adrian.klaver@aklaver.com