plv8

plv8 : PL/JavaScript (v8) trusted procedural language

Overview

Packages

Source

pig build pkg plv8;		# 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 plv8;		# install via package name, for the active PG version

pig install plv8 -v 18;   # install for PG 18
pig install plv8 -v 17;   # install for PG 17
pig install plv8 -v 16;   # install for PG 16
pig install plv8 -v 15;   # install for PG 15
pig install plv8 -v 14;   # install for PG 14

Create this extension with:

CREATE EXTENSION plv8;

Usage

Sources:

• README
• Built-ins
• Configuration
• Changes
• Control
• SQL template

plv8 provides a trusted JavaScript procedural language powered by V8. This page follows upstream 3.2.5, including its effective-user crash fixes and PostgreSQL 19 support.

Basic use

CREATE EXTENSION plv8;

SELECT plv8_version();
SELECT plv8_info();

DO $$ plv8.elog(NOTICE, plv8.version); $$ LANGUAGE plv8;

CREATE FUNCTION plv8_test(keys text[], vals text[]) RETURNS json AS $$
  let out = {};
  for (let i = 0; i < keys.length; i++) out[keys[i]] = vals[i];
  return out;
$$ LANGUAGE plv8 IMMUTABLE STRICT;

Common built-ins

• plv8.elog(level, ...): emit PostgreSQL log or client messages.
• plv8.execute(sql [, args]): run SQL and return rows or affected-row count.
• plv8.prepare(...), PreparedPlan.execute(), PreparedPlan.cursor(): prepared SPI access.
• plv8.subtransaction(fn): run a group of SPI operations atomically.
• plv8.find_function(...): call another PLV8 function by name.
• plv8.memory_usage(): inspect V8 heap usage for the current session.
• plv8.run_script(source, name): evaluate named script text.

Runtime settings

SET plv8.start_proc = 'plv8_init';
SET plv8.execution_timeout = 60;
SET plv8.memory_limit = 512;

• plv8.start_proc
• plv8.v8_flags
• plv8.execution_timeout
• plv8.memory_limit

Caveats

• The 3.2.5 CI matrix covers PostgreSQL 14–19. PostgreSQL-major support is separate from the versions available in downstream packages.
• Creating the extension requires a superuser; the installed JavaScript language is trusted, which does not make the extension itself installable by an unprivileged user. plv8_info() has its public execution privilege revoked by the installation SQL.
• Version 3.2.5 fixes crashes when a cached function runs under a different effective user via SECURITY DEFINER or SET ROLE, or after plv8_reset(), and when an exception message cannot be converted to a string.
• Each session has its own global JavaScript runtime; switching roles initializes a separate runtime context.
• plv8.execution_timeout only applies when the extension is compiled with execution-timeout support.