stringify non-string values in jsonb

with_stringified_values.sql

-- migrate:up
CREATE OR REPLACE FUNCTION with_stringified_values(input jsonb)
  RETURNS jsonb
  LANGUAGE plpgsql AS
$func$
DECLARE
   _key   text;
   _value text;
   _vals text[] := '{}'::text[];
   _output jsonb := '{}'::jsonb;
BEGIN
    FOR _key, _value IN
       SELECT * FROM jsonb_each_text($1)
    LOOP
       _vals = array_append(array_append(_vals, _key), _value);
    END LOOP;

    RETURN jsonb_object(_vals);
END
$func$;

do $$
  begin
    assert (
      select with_stringified_values('{"a":1, "b": "c"}'::jsonb)
    ) = '{"a":"1", "b":"c"}'::jsonb, 'Should convert non-str vals to str';
  end;
$$;


-- migrate:down
DROP function with_stringified_values;