Passing a row type dynamically to jsonb_populate_recordset

Question

I'm working on some code to unwind data packed into a JSONB with a regular format for passthrough to another system.

-- Postgres 11.4.
-- The format of the JSON is knowable in advance, it's specified in the record.
-- I've got a custom type for the JSON format defined.

Here's the stripped down passthrough table:

CREATE TABLE IF NOT EXISTS data.domo_passthrough (
    id           uuid NOT NULL DEFAULT extensions.gen_random_uuid (),
    type_name    text NOT NULL DEFAULT NULL, 
    report_data  jsonb NOT NULL DEFAULT '{}',

CONSTRAINT domo_passthrough_id_pkey
    PRIMARY KEY (id)
);

The report_data field holds the packed data, the type_name field includes the name of the format, like this one:

create type data.table_stats_type as (
    table_name text, 
    record_count integer,
    table_number integer)

This code works properly to unpack the data into the three columns defined in the type:

select expanded_data.*
  from domo_passthrough,
       jsonb_populate_recordset(null::table_stats_type, report_data) as expanded_data;

What I'd like to do, if possible, is to pass in the type_name as an argument to jsonb_populate_recordset:

select expanded_data.*
  from domo_passthrough,
       jsonb_populate_recordset(null::type_name, report_data) as expanded_data;

This does not work as null::type_name returns an error:

ERROR:  type "type_name" does not exist
LINE 3:        jsonb_populate_recordset(null::type_name, report_data..

Fair. The type_name is a text, not a literal. I'm hoping that there is a tidy way to do what I'm after. (I understand that it's on me at that point to not screw up the type name assignments in the data.) Possibilities:

-- Some kind of ::casting operation, but I can't figure out what type I'd use between null:: and type_name. I've found the pg_typeof function, but don't see a way to apply it to build in code.

-- Dynamic SQL in a function. This seems like it should be possible, but I'm hoping for something simpler.

-- Some other feature or option I'm unaware of.

RETURN SETOF Function?

Thanks for the comment, I figured I'd try writing a function...and I got stumped. It's always tricky to get dynamic results out of SQL. I'm not complaining about that...but this is one time I'd like to have a generalized tool. It sounds like RETURN SETOF RECORD ought to work, but I haven't succeeded. I've look through a fair few threads and the docs, but I'm still stumped. Here's a PG/pgSQL function as I couldn't get the pure SQL version to work:

DROP FUNCTION IF EXISTS api.domo_passthrough_expand (text, jsonb);
CREATE FUNCTION api.domo_passthrough_expand(type_name text, packed_data jsonb) 
    RETURNS SETOF record AS
$BODY$
BEGIN

    RETURN QUERY EXECUTE FORMAT
   'select *
      from jsonb_populate_recordset(null::%1$I, %2$I) as expanded_data;',
           type_name,
           packed_data;
END;
$BODY$
LANGUAGE plpgsql;

ALTER FUNCTION api.domo_passthrough_expand(text, jsonb) OWNER TO user_bender;

select expanded.* 

  from domo_passthrough,
        domo_passthrough_expand(domo_passthrough.type_name,domo_passthrough.report_data)

ERROR:  a column definition list is required for functions returning "record"
LINE 4:      domo_passthrough_expand(domo_passthrough.type_name,domo...

Is there a way to do my expansion generically with the help of a function? If there isn't, I can approach things another way, but I'd prefer to have it all Postgres-side.