Package mapnik

If an optional settings file exists, inherit its
environment settings before loading the mapnik library.

This feature is intended for customized packages of mapnik.

The settings file should be a python file with an 'env' variable
that declares a dictionary of key:value pairs to push into the
global process environment, if not already set, like:

    env = {'ICU_DATA':'/usr/local/share/icu/'}

Wrapper around CreateDatasource.

Create a Mapnik Datasource using a dictionary of parameters.

Keywords must include:

  type='plugin_name' # e.g. type='gdal'

See the convenience factory methods of each input plugin for
details on additional required keyword arguments.

Create a Shapefile Datasource.

Required keyword arguments:
  file -- path to shapefile without extension

Optional keyword arguments:
  base -- path prefix (default None)
  encoding -- file encoding (default 'utf-8')

>>> from mapnik import Shapefile, Layer
>>> shp = Shapefile(base='/home/mapnik/data',file='world_borders')
>>> lyr = Layer('Shapefile Layer')
>>> lyr.datasource = shp

Create a CSV Datasource.

    Required keyword arguments:
      file -- path to csv

    Optional keyword arguments:
      inline -- inline CSV string (if provided 'file' argument will be ignored and non-needed)
      base -- path prefix (default None)
      encoding -- file encoding (default 'utf-8')
      row_limit -- integer limit of rows to return (default: 0)
      strict -- throw an error if an invalid row is encountered
      escape -- The escape character to use for parsing data
      quote -- The quote character to use for parsing data
      separator -- The separator character to use for parsing data
      headers -- A comma separated list of header names that can be set to add headers to data that lacks them
      filesize_max -- The maximum filesize in MB that will be accepted

    >>> from mapnik import CSV
    >>> csv = CSV(file='test.csv')

    >>> from mapnik import CSV
    >>> csv = CSV(inline='''wkt,Name
"POINT (120.15 48.47)","Winthrop, WA"''')

    For more information see https://github.com/mapnik/mapnik/wiki/CSV-Plugin

    

Create a GeoJSON Datasource.

Required keyword arguments:
  file -- path to json

Optional keyword arguments:
  encoding -- file encoding (default 'utf-8')
  base -- path prefix (default None)

>>> from mapnik import GeoJSON
>>> geojson = GeoJSON(file='test.json')

Create a PostGIS Datasource.

Required keyword arguments:
  dbname -- database name to connect to
  table -- table name or subselect query

  *Note: if using subselects for the 'table' value consider also
   passing the 'geometry_field' and 'srid' and 'extent_from_subquery'
   options and/or specifying the 'geometry_table' option.

Optional db connection keyword arguments:
  user -- database user to connect as (default: see postgres docs)
  password -- password for database user (default: see postgres docs)
  host -- portgres hostname (default: see postgres docs)
  port -- postgres port (default: see postgres docs)
  initial_size -- integer size of connection pool (default: 1)
  max_size -- integer max of connection pool (default: 10)
  persist_connection -- keep connection open (default: True)

Optional table-level keyword arguments:
  extent -- manually specified data extent (comma delimited string, default: None)
  estimate_extent -- boolean, direct PostGIS to use the faster, less accurate `estimate_extent` over `extent` (default: False)
  extent_from_subquery -- boolean, direct Mapnik to query Postgis for the extent of the raw 'table' value (default: uses 'geometry_table')
  geometry_table -- specify geometry table to use to look up metadata (default: automatically parsed from 'table' value)
  geometry_field -- specify geometry field to use (default: first entry in geometry_columns)
  srid -- specify srid to use (default: auto-detected from geometry_field)
  row_limit -- integer limit of rows to return (default: 0)
  cursor_size -- integer size of binary cursor to use (default: 0, no binary cursor is used)

>>> from mapnik import PostGIS, Layer
>>> params = dict(dbname='mapnik',table='osm',user='postgres',password='gis')
>>> params['estimate_extent'] = False
>>> params['extent'] = '-20037508,-19929239,20037508,19929239'
>>> postgis = PostGIS(**params)
>>> lyr = Layer('PostGIS Layer')
>>> lyr.datasource = postgis

Create a Raster (Tiff) Datasource.

Required keyword arguments:
  file -- path to stripped or tiled tiff
  lox -- lowest (min) x/longitude of tiff extent
  loy -- lowest (min) y/latitude of tiff extent
  hix -- highest (max) x/longitude of tiff extent
  hiy -- highest (max) y/latitude of tiff extent

Hint: lox,loy,hix,hiy make a Mapnik Box2d

Optional keyword arguments:
  base -- path prefix (default None)
  multi -- whether the image is in tiles on disk (default False)

Multi-tiled keyword arguments:
  x_width -- virtual image number of tiles in X direction (required)
  y_width -- virtual image number of tiles in Y direction (required)
  tile_size -- if an image is in tiles, how large are the tiles (default 256)
  tile_stride -- if an image is in tiles, what's the increment between rows/cols (default 1)

>>> from mapnik import Raster, Layer
>>> raster = Raster(base='/home/mapnik/data',file='elevation.tif',lox=-122.8,loy=48.5,hix=-122.7,hiy=48.6)
>>> lyr = Layer('Tiff Layer')
>>> lyr.datasource = raster

Create a GDAL Raster Datasource.

Required keyword arguments:
  file -- path to GDAL supported dataset

Optional keyword arguments:
  base -- path prefix (default None)
  shared -- boolean, open GdalDataset in shared mode (default: False)
  bbox -- tuple (minx, miny, maxx, maxy). If specified, overrides the bbox detected by GDAL.

>>> from mapnik import Gdal, Layer
>>> dataset = Gdal(base='/home/mapnik/data',file='elevation.tif')
>>> lyr = Layer('GDAL Layer from TIFF file')
>>> lyr.datasource = dataset

Create a Oracle Spatial (10g) Vector Datasource.

Required keyword arguments:
  user -- database user to connect as
  password -- password for database user
  host -- oracle host to connect to (does not refer to SID in tsnames.ora)
  table -- table name or subselect query

Optional keyword arguments:
  initial_size -- integer size of connection pool (default 1)
  max_size -- integer max of connection pool (default 10)
  extent -- manually specified data extent (comma delimited string, default None)
  estimate_extent -- boolean, direct Oracle to use the faster, less accurate estimate_extent() over extent() (default False)
  encoding -- file encoding (default 'utf-8')
  geometry_field -- specify geometry field (default 'GEOLOC')
  use_spatial_index -- boolean, force the use of the spatial index (default True)

>>> from mapnik import Occi, Layer
>>> params = dict(host='myoracle',user='scott',password='tiger',table='test')
>>> params['estimate_extent'] = False
>>> params['extent'] = '-20037508,-19929239,20037508,19929239'
>>> oracle = Occi(**params)
>>> lyr = Layer('Oracle Spatial Layer')
>>> lyr.datasource = oracle

Create a OGR Vector Datasource.

Required keyword arguments:
  file -- path to OGR supported dataset
  layer -- name of layer to use within datasource (optional if layer_by_index or layer_by_sql is used)

Optional keyword arguments:
  layer_by_index -- choose layer by index number instead of by layer name or sql.
  layer_by_sql -- choose layer by sql query number instead of by layer name or index.
  base -- path prefix (default None)
  encoding -- file encoding (default 'utf-8')

>>> from mapnik import Ogr, Layer
>>> datasource = Ogr(base='/home/mapnik/data',file='rivers.geojson',layer='OGRGeoJSON')
>>> lyr = Layer('OGR Layer from GeoJSON file')
>>> lyr.datasource = datasource

Create a SQLite Datasource.

Required keyword arguments:
  file -- path to SQLite database file
  table -- table name or subselect query

Optional keyword arguments:
  base -- path prefix (default None)
  encoding -- file encoding (default 'utf-8')
  extent -- manually specified data extent (comma delimited string, default None)
  metadata -- name of auxillary table containing record for table with xmin, ymin, xmax, ymax, and f_table_name
  geometry_field -- name of geometry field (default 'the_geom')
  key_field -- name of primary key field (default 'OGC_FID')
  row_offset -- specify a custom integer row offset (default 0)
  row_limit -- specify a custom integer row limit (default 0)
  wkb_format -- specify a wkb type of 'spatialite' (default None)
  use_spatial_index -- boolean, instruct sqlite plugin to use Rtree spatial index (default True)

>>> from mapnik import SQLite, Layer
>>> sqlite = SQLite(base='/home/mapnik/data',file='osm.db',table='osm',extent='-20037508,-19929239,20037508,19929239')
>>> lyr = Layer('SQLite Layer')
>>> lyr.datasource = sqlite

Create a Rasterlite Datasource.

Required keyword arguments:
  file -- path to Rasterlite database file
  table -- table name or subselect query

Optional keyword arguments:
  base -- path prefix (default None)
  extent -- manually specified data extent (comma delimited string, default None)

>>> from mapnik import Rasterlite, Layer
>>> rasterlite = Rasterlite(base='/home/mapnik/data',file='osm.db',table='osm',extent='-20037508,-19929239,20037508,19929239')
>>> lyr = Layer('Rasterlite Layer')
>>> lyr.datasource = rasterlite

Create a Osm Datasource.

Required keyword arguments:
  file -- path to OSM file

Optional keyword arguments:
  encoding -- file encoding (default 'utf-8')
  url -- url to fetch data (default None)
  bbox -- data bounding box for fetching data (default None)

>>> from mapnik import Osm, Layer
>>> datasource = Osm(file='test.osm')
>>> lyr = Layer('Osm Layer')
>>> lyr.datasource = datasource

Create a Python Datasource.

>>> from mapnik import Python, PythonDatasource
>>> datasource = Python('PythonDataSource')
>>> lyr = Layer('Python datasource')
>>> lyr.datasource = datasource