App::Info::RDBMS::PostgreSQL - Information about PostgreSQL

  use App::Info::RDBMS::PostgreSQL;

  my $pg = App::Info::RDBMS::PostgreSQL->new;

  if ($pg->installed) {
      print "App name: ", $pg->name, "\n";
      print "Version:  ", $pg->version, "\n";
      print "Bin dir:  ", $pg->bin_dir, "\n";
  } else {
      print "PostgreSQL is not installed. :-(\n";
  }

App::Info::RDBMS::PostgreSQL supplies information about the PostgreSQL database server installed on the local system. It implements all of the methods defined by App::Info::RDBMS. Methods that trigger events will trigger them only the first time they're called (See App::Info for documentation on handling events). To start over (after, say, someone has installed PostgreSQL) construct a new App::Info::RDBMS::PostgreSQL object to aggregate new meta data.

Some of the methods trigger the same events. This is due to cross-calling of shared subroutines. However, any one event should be triggered no more than once. For example, although the info event "Executing `pg_config --version`" is documented for the methods name(), version(), major_version(), minor_version(), and patch_version(), rest assured that it will only be triggered once, by whichever of those four methods is called first.

  my $pg = App::Info::RDBMS::PostgreSQL->new(@params);

Returns an App::Info::RDBMS::PostgreSQL object. See App::Info for a complete description of argument parameters.

When it called, new() searches the file system for an executable named for the list returned by search_exe_names(), usually pg_config, in the list of directories returned by search_bin_dirs(). If found, pg_config will be called by the object methods below to gather the data necessary for each. If pg_config cannot be found, then PostgreSQL is assumed not to be installed, and each of the object methods will return undef.

new() also takes a number of optional parameters in addition to those documented for App::Info. These parameters allow you to specify alternate names for PostgreSQL executables (other than pg_config, which you specify via the search_exe_names parameter). These parameters are:

search_postgres_names

search_createdb_names

search_createlang_names

search_createuser_names

search_dropd_names

search_droplang_names

search_dropuser_names

search_initdb_names

search_pg_dump_names

search_pg_dumpall_names

search_pg_restore_names

search_postmaster_names

search_psql_names

search_vacuumdb_names

Events:

info

Looking for pg_config

confirm

Path to pg_config?

unknown

Path to pg_config?

  my $key_name = App::Info::RDBMS::PostgreSQL->key_name;

Returns the unique key name that describes this class. The value returned is the string "PostgreSQL".

  print "PostgreSQL is ", ($pg->installed ? '' : 'not '), "installed.\n";

Returns true if PostgreSQL is installed, and false if it is not. App::Info::RDBMS::PostgreSQL determines whether PostgreSQL is installed based on the presence or absence of the pg_config application on the file system as found when new() constructed the object. If PostgreSQL does not appear to be installed, then all of the other object methods will return empty values.

  my $name = $pg->name;

Returns the name of the application. App::Info::RDBMS::PostgreSQL parses the name from the system call `pg_config --version`.

Events:

info

Executing `pg_config --version`

error

Failed to find PostgreSQL version with `pg_config --version`

Unable to parse name from string

Unable to parse version from string

Failed to parse PostgreSQL version parts from string

unknown

Enter a valid PostgreSQL name

  my $version = $pg->version;

Returns the PostgreSQL version number. App::Info::RDBMS::PostgreSQL parses the version number from the system call `pg_config --version`.

Events:

info

Executing `pg_config --version`

error

Failed to find PostgreSQL version with `pg_config --version`

Unable to parse name from string

Unable to parse version from string

Failed to parse PostgreSQL version parts from string

unknown

Enter a valid PostgreSQL version number

  my $major_version = $pg->major_version;

Returns the PostgreSQL major version number. App::Info::RDBMS::PostgreSQL parses the major version number from the system call `pg_config --version`. For example, if version() returns "7.1.2", then this method returns "7".

Events:

info

Executing `pg_config --version`

error

Failed to find PostgreSQL version with `pg_config --version`

Unable to parse name from string

Unable to parse version from string

Failed to parse PostgreSQL version parts from string

unknown

Enter a valid PostgreSQL major version number

  my $minor_version = $pg->minor_version;

Returns the PostgreSQL minor version number. App::Info::RDBMS::PostgreSQL parses the minor version number from the system call `pg_config --version`. For example, if version() returns "7.1.2", then this method returns "2".

Events:

info

Executing `pg_config --version`

error

Failed to find PostgreSQL version with `pg_config --version`

Unable to parse name from string

Unable to parse version from string

Failed to parse PostgreSQL version parts from string

unknown

Enter a valid PostgreSQL minor version number

  my $patch_version = $pg->patch_version;

Returns the PostgreSQL patch version number. App::Info::RDBMS::PostgreSQL parses the patch version number from the system call `pg_config --version`. For example, if version() returns "7.1.2", then this method returns "1".

Events:

info

Executing `pg_config --version`

error

Failed to find PostgreSQL version with `pg_config --version`

Unable to parse name from string

Unable to parse version from string

Failed to parse PostgreSQL version parts from string

unknown

Enter a valid PostgreSQL minor version number

  my $exe = $pg->executable;

Returns the full path to the PostgreSQL server executable, which is named postgres. This method does not use the executable names returned by search_exe_names(); those executable names are used to search for pg_config only (in new()).

When it called, executable() checks for an executable named postgres in the directory returned by bin_dir().

Note that executable() is simply an alias for postgres().

Events:

info

Looking for postgres executable

confirm

Path to postgres executable?

unknown

Path to postgres executable?

  my $bin_dir = $pg->bin_dir;

Returns the PostgreSQL binary directory path. App::Info::RDBMS::PostgreSQL gathers the path from the system call `pg_config --bindir`.

Events:

info

Executing `pg_config --bindir`

error

Cannot find bin directory

unknown

Enter a valid PostgreSQL bin directory

  my $inc_dir = $pg->inc_dir;

Returns the PostgreSQL include directory path. App::Info::RDBMS::PostgreSQL gathers the path from the system call `pg_config --includedir`.

Events:

info

Executing `pg_config --includedir`

error

Cannot find include directory

unknown

Enter a valid PostgreSQL include directory

  my $lib_dir = $pg->lib_dir;

Returns the PostgreSQL library directory path. App::Info::RDBMS::PostgreSQL gathers the path from the system call `pg_config --libdir`.

Events:

info

Executing `pg_config --libdir`

error

Cannot find library directory

unknown

Enter a valid PostgreSQL library directory

  my $so_lib_dir = $pg->so_lib_dir;

Returns the PostgreSQL shared object library directory path. App::Info::RDBMS::PostgreSQL gathers the path from the system call `pg_config --pkglibdir`.

Events:

info

Executing `pg_config --pkglibdir`

error

Cannot find shared object library directory

unknown

Enter a valid PostgreSQL shared object library directory

  my $configure = $pg->configure;

Returns the options with which the PostgreSQL server was configured. App::Info::RDBMS::PostgreSQL gathers the configure data from the system call `pg_config --configure`.

Events:

info

Executing `pg_config --configure`

error

Cannot find configure information

unknown

Enter PostgreSQL configuration options

  my $home_url = $pg->home_url;

Returns the PostgreSQL home page URL.

  my $download_url = $pg->download_url;

Returns the PostgreSQL download URL.

  my @search_exe_names = $app->search_exe_names;

Returns a list of possible names for pg_config executable. By default, only pg_config is returned (or pg_config.exe on Win32).

Note that this method is not used to search for the PostgreSQL server executable, only pg_config.

  my @search_bin_dirs = $app->search_bin_dirs;

Returns a list of possible directories in which to search an executable. Used by the new() constructor to find an executable to execute and collect application info. The found directory will also be returned by the bin_dir method.

The list of directories by default consists of the path as defined by File::Spec->path, as well as the following directories:

$ENV{POSTGRES_HOME}/bin (if $ENV{POSTGRES_HOME} exists)

$ENV{POSTGRES_LIB}/../bin (if $ENV{POSTGRES_LIB} exists)

/usr/local/pgsql/bin

/usr/local/postgres/bin

/opt/pgsql/bin

/usr/local/bin

/usr/local/sbin

/usr/bin

/usr/sbin

/bin

C:\Program Files\PostgreSQL\bin

These methods function just like the executable() method, except that they return different executables. PostgreSQL comes with a fair number of them; we provide these methods to provide a path to a subset of them. Each method, when called, checks for an executable in the directory returned by bin_dir(). The name of the executable must be one of the names returned by the corresponding search_*_names method.

The available executable methods are:

postgres

createdb

createlang

createuser

dropdb

droplang

dropuser

initdb

pg_dump

pg_dumpall

pg_restore

postmaster

psql

vacuumdb

And the corresponding search names methods are:

search_postgres_names

search_createdb_names

search_createlang_names

search_createuser_names

search_dropd_names

search_droplang_names

search_dropuser_names

search_initdb_names

search_pg_dump_names

search_pg_dumpall_names

search_pg_restore_names

search_postmaster_names

search_psql_names

search_vacuumdb_names

Events:

info

Looking for executable

confirm

Path to executable?

unknown

Path to executable?

This module is stored in an open GitHub repository. Feel free to fork and contribute!

Please file bug reports via GitHub Issues or by sending mail to bug-App-Info@rt.cpan.org.

David E. Wheeler <david@justatheory.com> based on code by Sam Tregar <sam@tregar.com>.

App::Info documents the event handling interface.

App::Info::RDBMS is the App::Info::RDBMS::PostgreSQL parent class.

DBD::Pg is the DBI driver for connecting to PostgreSQL databases.

http://www.postgresql.org/ is the PostgreSQL home page.

Copyright (c) 2002-2011, David E. Wheeler. Some Rights Reserved.

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.