mapnik/bindings/python/mapnik_datasource.cpp

201 lines
6.9 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2006 Artem Pavlenko, Jean-Francois Doyon
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*****************************************************************************/
// boost
#include <boost/python.hpp>
#include <boost/python/detail/api_placeholder.hpp>
#include <boost/noncopyable.hpp>
// stl
#include <sstream>
#include <vector>
// mapnik
#include <mapnik/box2d.hpp>
#include <mapnik/coord.hpp>
#include <mapnik/query.hpp>
#include <mapnik/datasource.hpp>
#include <mapnik/datasource_cache.hpp>
#include <mapnik/feature_layer_desc.hpp>
#include <mapnik/memory_datasource.hpp>
using mapnik::datasource;
using mapnik::memory_datasource;
using mapnik::layer_descriptor;
using mapnik::attribute_descriptor;
namespace
{
//user-friendly wrapper that uses Python dictionary
using namespace boost::python;
std::shared_ptr<mapnik::datasource> create_datasource(dict const& d)
{
mapnik::parameters params;
boost::python::list keys=d.keys();
for (int i=0; i < len(keys); ++i)
{
std::string key = extract<std::string>(keys[i]);
object obj = d[key];
if (PyUnicode_Check(obj.ptr()))
{
PyObject* temp = PyUnicode_AsUTF8String(obj.ptr());
if (temp)
{
#if PY_VERSION_HEX >= 0x03000000
char* c_str = PyBytes_AsString(temp);
#else
char* c_str = PyString_AsString(temp);
#endif
params[key] = std::string(c_str);
Py_DecRef(temp);
}
continue;
}
extract<std::string> ex0(obj);
extract<mapnik::value_integer> ex1(obj);
extract<double> ex2(obj);
if (ex0.check())
{
params[key] = ex0();
}
else if (ex1.check())
{
params[key] = ex1();
}
else if (ex2.check())
{
params[key] = ex2();
}
}
return mapnik::datasource_cache::instance().create(params);
}
boost::python::dict describe(std::shared_ptr<mapnik::datasource> const& ds)
{
boost::python::dict description;
mapnik::layer_descriptor ld = ds->get_descriptor();
description["type"] = ds->type();
description["name"] = ld.get_name();
description["geometry_type"] = ds->get_geometry_type();
description["encoding"] = ld.get_encoding();
return description;
}
boost::python::list fields(std::shared_ptr<mapnik::datasource> const& ds)
{
boost::python::list flds;
if (ds)
{
layer_descriptor ld = ds->get_descriptor();
std::vector<attribute_descriptor> const& desc_ar = ld.get_descriptors();
std::vector<attribute_descriptor>::const_iterator it = desc_ar.begin();
std::vector<attribute_descriptor>::const_iterator end = desc_ar.end();
for (; it != end; ++it)
{
flds.append(it->get_name());
}
}
return flds;
}
boost::python::list field_types(std::shared_ptr<mapnik::datasource> const& ds)
{
boost::python::list fld_types;
if (ds)
{
layer_descriptor ld = ds->get_descriptor();
std::vector<attribute_descriptor> const& desc_ar = ld.get_descriptors();
std::vector<attribute_descriptor>::const_iterator it = desc_ar.begin();
std::vector<attribute_descriptor>::const_iterator end = desc_ar.end();
for (; it != end; ++it)
{
unsigned type = it->get_type();
if (type == mapnik::Integer)
// this crashes, so send back strings instead
//fld_types.append(boost::python::object(boost::python::handle<>(&PyInt_Type)));
fld_types.append(boost::python::str("int"));
else if (type == mapnik::Float)
fld_types.append(boost::python::str("float"));
else if (type == mapnik::Double)
fld_types.append(boost::python::str("float"));
else if (type == mapnik::String)
fld_types.append(boost::python::str("str"));
else if (type == mapnik::Boolean)
fld_types.append(boost::python::str("bool"));
else if (type == mapnik::Geometry)
fld_types.append(boost::python::str("geometry"));
else if (type == mapnik::Object)
fld_types.append(boost::python::str("object"));
else
fld_types.append(boost::python::str("unknown"));
}
}
return fld_types;
}}
mapnik::parameters const& (mapnik::datasource::*params_const)() const = &mapnik::datasource::params;
void export_datasource()
{
using namespace boost::python;
enum_<mapnik::datasource::datasource_t>("DataType")
.value("Vector",mapnik::datasource::Vector)
.value("Raster",mapnik::datasource::Raster)
;
enum_<mapnik::datasource::geometry_t>("DataGeometryType")
.value("Point",mapnik::datasource::Point)
.value("LineString",mapnik::datasource::LineString)
.value("Polygon",mapnik::datasource::Polygon)
.value("Collection",mapnik::datasource::Collection)
;
class_<datasource,std::shared_ptr<datasource>,
boost::noncopyable>("Datasource",no_init)
.def("type",&datasource::type)
.def("geometry_type",&datasource::get_geometry_type)
.def("describe",&describe)
.def("envelope",&datasource::envelope)
.def("features",&datasource::features)
.def("fields",&fields)
.def("field_types",&field_types)
.def("features_at_point",&datasource::features_at_point, (arg("coord"),arg("tolerance")=0))
.def("params",make_function(params_const,return_value_policy<copy_const_reference>()),
"The configuration parameters of the data source. "
"These vary depending on the type of data source.")
;
def("CreateDatasource",&create_datasource);
class_<memory_datasource, bases<datasource>, boost::noncopyable>("MemoryDatasource", init<>())
.def("add_feature",&memory_datasource::push,
"Adds a Feature:\n"
">>> ms = MemoryDatasource()\n"
">>> feature = Feature(1)\n"
">>> ms.add_feature(Feature(1))\n")
.def("num_features",&memory_datasource::size)
;
}