/***************************************************************************** * * This file is part of Mapnik (c++ mapping toolkit) * * Copyright (C) 2012 Artem Pavlenko * * 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 * *****************************************************************************/ #include "geojson_datasource.hpp" #include "geojson_featureset.hpp" #include #include // boost #include #include #include #include #include #include #include // mapnik #include #include #include #include #include #include #include #include #include #include #include #include using mapnik::datasource; using mapnik::parameters; DATASOURCE_PLUGIN(geojson_datasource) struct attr_value_converter : public boost::static_visitor { mapnik::eAttributeType operator() (mapnik::value_integer /*val*/) const { return mapnik::Integer; } mapnik::eAttributeType operator() (double /*val*/) const { return mapnik::Double; } mapnik::eAttributeType operator() (float /*val*/) const { return mapnik::Double; } mapnik::eAttributeType operator() (bool /*val*/) const { return mapnik::Boolean; } mapnik::eAttributeType operator() (std::string const& /*val*/) const { return mapnik::String; } mapnik::eAttributeType operator() (mapnik::value_unicode_string const& /*val*/) const { return mapnik::String; } mapnik::eAttributeType operator() (mapnik::value_null const& /*val*/) const { return mapnik::String; } }; geojson_datasource::geojson_datasource(parameters const& params) : datasource(params), type_(datasource::Vector), desc_(geojson_datasource::name(), *params.get("encoding","utf-8")), file_(*params.get("file","")), extent_(), tr_(new mapnik::transcoder(*params.get("encoding","utf-8"))), features_(), tree_(16,1) { if (file_.empty()) throw mapnik::datasource_exception("GeoJSON Plugin: missing parameter"); boost::optional base = params.get("base"); if (base) { file_ = *base + "/" + file_; } using base_iterator_type = std::istreambuf_iterator; #if defined (_WINDOWS) std::ifstream is(mapnik::utf8_to_utf16(file_),std::ios_base::in | std::ios_base::binary); #else std::ifstream is(file_.c_str(),std::ios_base::in | std::ios_base::binary); #endif if (!is.is_open()) { throw mapnik::datasource_exception("GeoJSON Plugin: could not open: '" + file_ + "'"); } boost::spirit::multi_pass begin = boost::spirit::make_default_multi_pass(base_iterator_type(is)); boost::spirit::multi_pass end = boost::spirit::make_default_multi_pass(base_iterator_type()); mapnik::context_ptr ctx = std::make_shared(); mapnik::json::generic_json > json; // TODO - make it possible for this to be static const // by avoiding ctor taking arg - https://github.com/mapnik/mapnik/pull/2231 mapnik::json::feature_collection_parser > p(json, ctx,*tr_); bool result = p.parse(begin,end, features_); if (!result) { throw mapnik::datasource_exception("geojson_datasource: Failed parse GeoJSON file '" + file_ + "'"); } std::size_t count=0; for (mapnik::feature_ptr const& f : features_) { mapnik::box2d box = f->envelope(); if (count == 0) { extent_ = box; mapnik::feature_kv_iterator f_itr = f->begin(); mapnik::feature_kv_iterator f_end = f->end(); for ( ;f_itr!=f_end; ++f_itr) { desc_.add_descriptor(mapnik::attribute_descriptor(std::get<0>(*f_itr), boost::apply_visitor(attr_value_converter(),std::get<1>(*f_itr).base()))); } } else { extent_.expand_to_include(box); } tree_.insert(box_type(point_type(box.minx(),box.miny()),point_type(box.maxx(),box.maxy())), count++); } } geojson_datasource::~geojson_datasource() { } const char * geojson_datasource::name() { return "geojson"; } boost::optional geojson_datasource::get_geometry_type() const { boost::optional result; int multi_type = 0; unsigned num_features = features_.size(); for (unsigned i = 0; i < num_features && i < 5; ++i) { mapnik::util::to_ds_type(features_[i]->paths(),result); if (result) { int type = static_cast(*result); if (multi_type > 0 && multi_type != type) { result.reset(mapnik::datasource::Collection); return result; } multi_type = type; } } return result; } mapnik::datasource::datasource_t geojson_datasource::type() const { return type_; } mapnik::box2d geojson_datasource::envelope() const { return extent_; } mapnik::layer_descriptor geojson_datasource::get_descriptor() const { return desc_; } mapnik::featureset_ptr geojson_datasource::features(mapnik::query const& q) const { // if the query box intersects our world extent then query for features mapnik::box2d const& b = q.get_bbox(); if (extent_.intersects(b)) { box_type box(point_type(b.minx(),b.miny()),point_type(b.maxx(),b.maxy())); return std::make_shared(features_, tree_.find(box)); } // otherwise return an empty featureset pointer return mapnik::featureset_ptr(); } mapnik::featureset_ptr geojson_datasource::features_at_point(mapnik::coord2d const& pt, double tol) const { mapnik::box2d query_bbox(pt, pt); query_bbox.pad(tol); mapnik::query q(query_bbox); std::vector const& desc = desc_.get_descriptors(); std::vector::const_iterator itr = desc.begin(); std::vector::const_iterator end = desc.end(); for ( ;itr!=end;++itr) { q.add_property_name(itr->get_name()); } return features(q); }