mapnik/utils/mapnik-index/process_geojson_file_x3.cpp

513 lines
17 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2016 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 "process_geojson_file_x3.hpp"
#if defined(MAPNIK_MEMORY_MAPPED_FILE)
#pragma GCC diagnostic push
#include <mapnik/warning_ignore.hpp>
#include <boost/interprocess/mapped_region.hpp>
#include <boost/interprocess/streams/bufferstream.hpp>
#include <boost/spirit/home/x3.hpp>
#pragma GCC diagnostic pop
#include <mapnik/mapped_memory_cache.hpp>
#else
#include <mapnik/util/file_io.hpp>
#endif
#include <mapnik/feature.hpp>
#include <mapnik/json/json_grammar_config.hpp>
#include <mapnik/json/geojson_grammar_x3_def.hpp>
#include <mapnik/json/unicode_string_grammar_x3_def.hpp>
#include <mapnik/json/positions_grammar_x3_def.hpp>
namespace {
enum well_known_names
{
type = 0,
geometry = 1,
coordinates = 2,
properties = 3
};
constexpr int feature_properties[] = {
well_known_names::type,
well_known_names::geometry,
well_known_names::properties}; // sorted
constexpr int geometry_properties[] = {
well_known_names::type,
well_known_names::coordinates}; // sorted
template <typename Keys>
std::string join(Keys const& keys)
{
std::string result;
bool first = true;
for (auto const& key : keys)
{
if (!first) result += ",";
result += "\"" + std::to_string(key) + "\"";
first = false;
}
return result;
}
template <typename Iterator, typename Keys>
bool has_keys(Iterator first1, Iterator last1, Keys const& keys)
{
auto first2 = std::begin(keys);
auto last2 = std::end(keys);
for (; first2 != last2; ++first1)
{
if (first1 == last1 || *first2 < std::get<0>(*first1))
return false;
if (!(std::get<0>(*first1) < *first2))
++first2;
}
return true;
}
template <typename Keys>
bool validate_geojson_feature(mapnik::json::geojson_value & value, Keys const& keys, bool verbose)
{
if (!value.is<mapnik::json::geojson_object>())
{
if (verbose) std::clog << "Expecting an GeoJSON object" << std::endl;
return false;
}
mapnik::json::geojson_object & feature = mapnik::util::get<mapnik::json::geojson_object>(value);
std::sort(feature.begin(), feature.end(), [](auto const& e0, auto const& e1)
{
return std::get<0>(e0) < std::get<0>(e1);
});
if (!has_keys(feature.begin(), feature.end(), feature_properties))
{
if (verbose) std::clog << "Expecting one of " << join(feature_properties) << std::endl;
return false;
}
for (auto & elem : feature)
{
auto const key = std::get<0>(elem);
if (key == well_known_names::geometry)
{
auto & geom_value = std::get<1>(elem);
if (!geom_value.is<mapnik::json::geojson_object>())
{
if (verbose) std::clog << "\"geometry\": xxx <-- expecting an JSON object here" << std::endl;
return false;
}
auto & geometry = mapnik::util::get<mapnik::json::geojson_object>(geom_value);
// sort by property name
std::sort(geometry.begin(), geometry.end(), [](auto const& e0, auto const& e1)
{
return std::get<0>(e0) < std::get<0>(e1);
});
if (!has_keys(geometry.begin(), geometry.end(), geometry_properties))
{
if (verbose) std::clog << "Expecting one of " << join(geometry_properties) << std::endl;
return false;
}
mapnik::geometry::geometry_types geom_type;
mapnik::json::positions const* coordinates = nullptr;
for (auto & elem2 : geometry)
{
auto const key2 = std::get<0>(elem2);
if (key2 == well_known_names::type)
{
auto const& geom_type_value = std::get<1>(elem2);
if (!geom_type_value.is<mapnik::geometry::geometry_types>())
{
if (verbose) std::clog << "\"type\": xxx <-- expecting an GeoJSON geometry type here" << std::endl;
return false;
}
geom_type = mapnik::util::get<mapnik::geometry::geometry_types>(geom_type_value);
if (geom_type == mapnik::geometry::geometry_types::GeometryCollection)
{
if (verbose) std::clog << "GeometryCollections are not allowed" << std::endl;;
return false;
}
}
else if (key2 == well_known_names::coordinates)
{
auto const& coordinates_value = std::get<1>(elem2);
if (!coordinates_value.is<mapnik::json::positions>())
{
if (verbose) std::clog << "\"coordinates\": xxx <-- expecting an GeoJSON positions here" << std::endl;
return false;
}
coordinates = &mapnik::util::get<mapnik::json::positions>(coordinates_value);
}
}
if (geom_type == mapnik::geometry::geometry_types::Point)
{
// expecting single position
if (!coordinates->is<mapnik::json::point>())
{
if (verbose) std::clog << "Expecting single position in Point" << std::endl;
return false;
}
}
else if (geom_type == mapnik::geometry::geometry_types::LineString)
{
// expecting
if (!coordinates->is<mapnik::json::ring>())
{
if (verbose) std::clog << "Expecting sequence of positions (ring) in LineString" << std::endl;
return false;
}
else
{
auto const& ring = mapnik::util::get<mapnik::json::ring>(*coordinates);
if (ring.size() < 2)
{
if (verbose) std::clog << "Expecting at least two coordinates in LineString" << std::endl;
return false;
}
}
}
else if (geom_type == mapnik::geometry::geometry_types::Polygon)
{
// expecting
if (!coordinates->is<mapnik::json::rings>())
{
if (verbose) std::clog << "Expecting an array of rings in Polygon" << std::endl;
return false;
}
else
{
auto const& rings = mapnik::util::get<mapnik::json::rings>(*coordinates);
if (rings.size() < 1)
{
if (verbose) std::clog << "Expecting at least one ring in Polygon" << std::endl;
return false;
}
for (auto const& ring : rings)
{
if (ring.size() < 4)
{
if (verbose) std::clog << "Expecting at least four coordinates in Polygon ring" << std::endl;
return false;
}
}
}
}
}
}
return true;
};
using box_type = mapnik::box2d<float>;
using boxes_type = std::vector<std::pair<box_type, std::pair<std::size_t, std::size_t>>>;
using base_iterator_type = char const*;
}
namespace mapnik { namespace json {
template <typename Box>
struct calculate_bounding_box
{
calculate_bounding_box(Box & box)
: box_(box) {}
void operator()(mapnik::json::point const& pt) const
{
box_.init(pt.x, pt.y);
}
void operator()(mapnik::json::ring const& ring) const
{
for (auto const& pt : ring)
{
if (!box_.valid()) box_.init(pt.x, pt.y);
else box_.expand_to_include(pt.x, pt.y);
}
}
void operator()(mapnik::json::rings const& rings) const
{
for (auto const& ring : rings)
{
operator()(ring);
break; // consider first ring only
}
}
void operator()(mapnik::json::rings_array const& rings_array) const
{
for (auto const& rings : rings_array)
{
operator()(rings);
}
}
template <typename T>
void operator() (T const& ) const {}
Box & box_;
};
namespace grammar {
namespace x3 = boost::spirit::x3;
using x3::lit;
using x3::omit;
using x3::raw;
using x3::char_;
using x3::eps;
struct feature_callback_tag;
auto on_feature_callback = [] (auto const& ctx)
{
// call our callback
x3::get<feature_callback_tag>(ctx)(_attr(ctx));
};
namespace {
auto const& geojson_value = geojson_grammar();
}
// extract bounding box from GeoJSON Feature
struct bracket_tag ;
auto check_brackets = [](auto const& ctx)
{
_pass(ctx) = (x3::get<bracket_tag>(ctx) > 0);
};
auto open_bracket = [](auto const& ctx)
{
++x3::get<bracket_tag>(ctx);
};
auto close_bracket = [](auto const& ctx)
{
--x3::get<bracket_tag>(ctx);
};
auto assign_range = [](auto const& ctx)
{
std::get<0>(_val(ctx)) = std::move(_attr(ctx));
};
auto assign_bbox = [](auto const& ctx)
{
std::get<1>(_val(ctx)) = std::move(_attr(ctx));
};
auto extract_bounding_box = [](auto const& ctx)
{
mapnik::box2d<float> bbox;
calculate_bounding_box<mapnik::box2d<float>> visitor(bbox);
mapnik::util::apply_visitor(visitor, _attr(ctx));
_val(ctx) = std::move(bbox);
};
auto const coordinates_rule = x3::rule<struct coordinates_rule_tag, mapnik::box2d<float> > {}
= lit("\"coordinates\"") >> lit(':') >> positions_rule[extract_bounding_box];
auto const bounding_box = x3::rule<struct bounding_box_rule_tag, std::tuple<boost::iterator_range<base_iterator_type>,mapnik::box2d<float>>> {}
= raw[lit('{')[open_bracket] >> *(eps[check_brackets] >>
(lit("\"FeatureCollection\"") > eps(false)
|
lit('{')[open_bracket]
|
lit('}')[close_bracket]
|
coordinates_rule[assign_bbox]
|
omit[geojson_string]
|
omit[char_]))][assign_range];
auto const feature = bounding_box[on_feature_callback];
auto const key_value_ = omit[geojson_string] > lit(':') > omit[geojson_value] ;
auto const features = lit("\"features\"")
> lit(':') > lit('[') > -(omit[feature] % lit(',')) > lit(']');
auto const type = lit("\"type\"") > lit(':') > lit("\"FeatureCollection\"");
auto const feature_collection = x3::rule<struct feature_collection_tag> {}
= lit('{') > (( type | features | key_value_) % lit(',')) > lit('}');
}}}
namespace {
struct collect_features
{
collect_features(std::vector<mapnik::json::geojson_value> & values)
: values_(values) {}
void operator() (mapnik::json::geojson_value && val) const
{
values_.push_back(std::move(val));
}
std::vector<mapnik::json::geojson_value> & values_;
};
template <typename Iterator, typename Boxes>
struct extract_positions
{
extract_positions(Iterator start, Boxes & boxes)
: start_(start),
boxes_(boxes) {}
template <typename T>
void operator() (T const& val) const
{
auto const& r = std::get<0>(val);
mapnik::box2d<float> const& bbox = std::get<1>(val);
auto offset = std::distance(start_, r.begin());
auto size = std::distance(r.begin(), r.end());
boxes_.emplace_back(std::make_pair(bbox,std::make_pair(offset, size)));
//boxes_.emplace_back(std::make_tuple(bbox,offset, size));
}
Iterator start_;
Boxes & boxes_;
};
}
namespace mapnik { namespace detail {
template <typename T>
std::pair<bool,typename T::value_type::first_type> process_geojson_file_x3(T & boxes, std::string const& filename, bool validate_features, bool verbose)
{
using box_type = typename T::value_type::first_type;
box_type extent;
#if defined(MAPNIK_MEMORY_MAPPED_FILE)
mapnik::mapped_region_ptr mapped_region;
boost::optional<mapnik::mapped_region_ptr> memory =
mapnik::mapped_memory_cache::instance().find(filename, true);
if (!memory)
{
std::clog << "Error : cannot memory map " << filename << std::endl;
return std::make_pair(false, extent);
}
else
{
mapped_region = *memory;
}
base_iterator_type start = reinterpret_cast<base_iterator_type>(mapped_region->get_address());
base_iterator_type end = start + mapped_region->get_size();
#else
mapnik::util::file file(filename);
if (!file)
{
std::clog << "Error : cannot open " << filename << std::endl;
return std::make_pair(false, extent);
}
std::string file_buffer;
file_buffer.resize(file.size());
std::fread(&file_buffer[0], file.size(), 1, file.get());
base_iterator_type start = file_buffer.c_str();
base_iterator_type end = start + file_buffer.length();
#endif
using namespace boost::spirit;
using space_type = mapnik::json::grammar::space_type;
auto const* itr = start;
extract_positions<base_iterator_type, boxes_type> callback(itr, boxes);
mapnik::json::grammar::keys_map keys;
std::size_t bracket_counter = 0;
auto feature_collection_impl = x3::with<mapnik::json::grammar::bracket_tag>(std::ref(bracket_counter))
[x3::with<mapnik::json::keys_tag>(std::ref(keys))
[x3::with<mapnik::json::grammar::feature_callback_tag>(std::ref(callback))
[mapnik::json::grammar::feature_collection]
]];
try
{
bool result = x3::phrase_parse(itr, end, feature_collection_impl, space_type());
if (!result)
{
std::clog << "mapnik-index (GeoJSON) : could not extract bounding boxes from : '" << filename << "'" << std::endl;
return std::make_pair(false, extent);
}
}
catch (x3::expectation_failure<base_iterator_type> const& ex)
{
std::clog << ex.what() << std::endl;
std::clog << "Expected: " << ex.which();
std::clog << " Got: \"" << std::string(ex.where(), ex.where() + 200) << '"' << std::endl;
return std::make_pair(false, extent);
}
catch (std::exception const& ex)
{
std::clog << "Exception caught:" << ex.what() << std::endl;
return std::make_pair(false, extent);
}
auto feature_grammar = x3::with<mapnik::json::keys_tag>(std::ref(keys))
[ mapnik::json::grammar::geojson_value ];
for (auto const& item : boxes)
{
if (item.first.valid())
{
if (!extent.valid()) extent = item.first;
else extent.expand_to_include(item.first);
if (validate_features)
{
base_iterator_type feat_itr = start + item.second.first;
base_iterator_type feat_end = feat_itr + item.second.second;
mapnik::json::geojson_value feature_value;
try
{
bool result = x3::phrase_parse(feat_itr, feat_end, feature_grammar, space_type(), feature_value);
if (!result || feat_itr != feat_end)
{
if (verbose) std::clog << std::string(start + item.second.first, feat_end ) << std::endl;
return std::make_pair(false, extent);
}
}
catch (x3::expectation_failure<std::string::const_iterator> const& ex)
{
if (verbose) std::clog << ex.what() << std::endl;
return std::make_pair(false, extent);
}
catch (...)
{
return std::make_pair(false, extent);
}
if (!validate_geojson_feature(feature_value, keys, verbose))
{
return std::make_pair(false, extent);
}
}
}
}
return std::make_pair(true, extent);
}
template std::pair<bool,box_type> process_geojson_file_x3(boxes_type&, std::string const&, bool, bool);
}}