User:Ziga/xpg package

Name

xpg_package - installer for PostgreSQL extensions

Synopsis

% xpg_package load template1 tsearch2
% xpg_package -n my_schema load my_database ltree
% xpg_package update
% xpg_package install newsysviews
% xpg_package load my_database newsysviews

Description

Purpose: make it easy to manage extensions in your databases

A tool in the spirit of Perl CPAN installation tool, but for PostgresSQL and PgFoundry (and others).

Actions

The following are needed for sure. Probably more...

• update - fetch list of packages from internet. PgFoundry and such...
• look - get and unpack, cd into build, to allow user to build manually
• install - compile, test and install in system (/usr/share and such)
• load - load extension into a particular database/schema
• list - installed/loaded extensions
• unload - unload extension
• upgrade - upgrade installed package (perhaps load should do this?)

Requirements

• installation data should be kept in a database (Codd rule)
• it should be possible to keep multiple different versions of packages installed on system

How to handle source/binary (not a problem for SQL-only packages)

Two flavors:

• packages with schemas (these usually come with various PostgreSQL based applications -

now it is a major problem to upgrade such databases)

• packages which can be loaded into any schema

Must also manage: users, schemas, languages

Handle package installation transactionally - either install/upgrade cleanly or not at all (optionally disabled)

Installer should handle such stuff as is now done with shell scripts like build.sh.

packages provide:

• XML file describing the extension
• SQL install instructions
• SQL uninstall instructions
• SQL upgrade instructions (incremental for each version of extension)
• source + makefiles for compilable parts in C (makefiles can use pg_config)
• documentation in XML (compatible with PostgreSQL docbook documentation); this can be auto-merged into install of official PostgresSQL documentation when extension is installed

Metadata

Use of RDF (Semantic Web) technology could be useful for this

• name
• version
• download url
• author
• documentation
• maintainer
• dependencies
• link: page, wiki, forge, bugs, mailing-list

See also

• xpg_dump - database dumping tool