jsonb_plruby

plruby : Transform between jsonb and native Ruby data for PL/Ruby

Overview

Packages

Source

pig build pkg plruby;		# build rpm/deb

Install

Make sure PGDG and PIGSTY repo available:

pig repo add pgsql -u   # add both repo and update cache

Install this extension with pig:

pig install plruby;		# install via package name, for the active PG version
pig install jsonb_plruby;		# install by extension name, for the current active PG version

pig install jsonb_plruby -v 18;   # install for PG 18
pig install jsonb_plruby -v 17;   # install for PG 17
pig install jsonb_plruby -v 16;   # install for PG 16
pig install jsonb_plruby -v 15;   # install for PG 15
pig install jsonb_plruby -v 14;   # install for PG 14

Create this extension with:

CREATE EXTENSION jsonb_plruby CASCADE; -- requires plruby

Usage

Sources:

• PL/Ruby v2.5.0 README
• jsonb_plruby v1.0 control file
• jsonb_plruby v1.0 extension SQL

jsonb_plruby installs a PostgreSQL transform between jsonb and native Ruby values for the plruby language. A transformed jsonb argument becomes a Ruby Hash, Array, String, Integer, Float, true, false, or nil; compatible Ruby values can be returned directly as jsonb.

Install and Use the Transform

CREATE EXTENSION plruby;
CREATE EXTENSION jsonb_plruby;

CREATE FUNCTION ruby_mark_processed(jsonb)
RETURNS jsonb
LANGUAGE plruby
TRANSFORM FOR TYPE jsonb
AS $$
  value = args[0]
  value['processed'] = true
  value
$$;

SELECT ruby_mark_processed('{"id": 42}'::jsonb);

The transform is used only by functions that declare TRANSFORM FOR TYPE jsonb. Other PL/Ruby functions keep the language’s ordinary JSONB conversion behavior.

Objects and Caveats

• jsonb_to_plruby(internal) implements SQL-to-Ruby conversion.
• plruby_to_jsonb(internal) implements Ruby-to-SQL conversion.
• The extension version is 1.0, it requires plruby, and it is relocatable.
• Ruby Hash keys returned to PostgreSQL must be valid JSON object keys, and numeric/special values must be representable by PostgreSQL jsonb. Test nested values and numeric limits explicitly.
• PL/Ruby remains untrusted. Installing this transform does not sandbox Ruby code or reduce the privileges required to create PL/Ruby functions.