app/django/contrib/gis/db/backend/postgis/management.py
author Madhusudan C.S. <madhusudancs@gmail.com>
Mon, 08 Jun 2009 08:42:13 +0200
changeset 2406 6f966e1a80bc
parent 323 ff1a9aa48cfd
permissions -rw-r--r--
Changed the property that holds the minimum age required for Students to participate in a GHOP based program. Added a new property student_min_age_as_of to hold the DateTime from when the minimum age should be reached. Changed student_min_age property to now store the student minimum age as an integer. This all feel more user friendly then letting the program admin calculate the required DateTime. Storing the two properties is then still needed in this case since information might be lost otherwise when the program admin brings up the edit view. Reviewed by: Lennard de Rijk

"""
  This utility module is for obtaining information about the PostGIS
   installation.

  See PostGIS docs at Ch. 6.2.1 for more information on these functions.
"""
import re

def _get_postgis_func(func):
    "Helper routine for calling PostGIS functions and returning their result."
    from django.db import connection
    cursor = connection.cursor()
    cursor.execute('SELECT %s()' % func)
    row = cursor.fetchone()
    cursor.close()
    return row[0]

### PostGIS management functions ###
def postgis_geos_version():
    "Returns the version of the GEOS library used with PostGIS."
    return _get_postgis_func('postgis_geos_version')

def postgis_lib_version():
    "Returns the version number of the PostGIS library used with PostgreSQL."
    return _get_postgis_func('postgis_lib_version')

def postgis_proj_version():
    "Returns the version of the PROJ.4 library used with PostGIS."
    return _get_postgis_func('postgis_proj_version')

def postgis_version():
    "Returns PostGIS version number and compile-time options."
    return _get_postgis_func('postgis_version')

def postgis_full_version():
    "Returns PostGIS version number and compile-time options."
    return _get_postgis_func('postgis_full_version')

### Routines for parsing output of management functions. ###
version_regex = re.compile('^(?P<major>\d)\.(?P<minor1>\d)\.(?P<minor2>\d+)')
def postgis_version_tuple():
    "Returns the PostGIS version as a tuple."

    # Getting the PostGIS version
    version = postgis_lib_version()
    m = version_regex.match(version)
    if m:
        major = int(m.group('major'))
        minor1 = int(m.group('minor1'))
        minor2 = int(m.group('minor2'))
    else:
        raise Exception('Could not parse PostGIS version string: %s' % version)

    return (version, major, minor1, minor2)