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#include <mbgl/style/sources/geojson_source_impl.hpp>
#include <mbgl/style/source_observer.hpp>
#include <mbgl/style/parser.hpp>
#include <mbgl/tile/geojson_tile.hpp>
#include <mbgl/storage/file_source.hpp>
#include <mbgl/platform/log.hpp>
#include <mapbox/geojsonvt.hpp>
#include <mapbox/geojsonvt/convert.hpp>
#include <rapidjson/error/en.h>
#include <sstream>
namespace mbgl {
namespace style {
std::unique_ptr<mapbox::geojsonvt::GeoJSONVT> GeoJSONSource::Impl::parseGeoJSON(const JSValue& value) {
using namespace mapbox::geojsonvt;
Options options;
options.buffer = util::EXTENT / util::tileSize * 128;
options.extent = util::EXTENT;
try {
return std::make_unique<GeoJSONVT>(Convert::convert(value, 0), options);
} catch (const std::exception& ex) {
Log::Error(Event::ParseStyle, "Failed to parse GeoJSON data: %s", ex.what());
// Create an empty GeoJSON VT object to make sure we're not infinitely waiting for
// tiles to load.
return std::make_unique<GeoJSONVT>(std::vector<ProjectedFeature>{}, options);
}
}
std::unique_ptr<GeoJSONSource> GeoJSONSource::Impl::parse(const std::string& id, const JSValue& value) {
// We should probably split this up to have URLs in the url property, and actual data
// in the data property. Until then, we're going to detect the content based on the
// object type.
if (!value.HasMember("data")) {
Log::Error(Event::ParseStyle, "GeoJSON source must have a data value");
return nullptr;
}
const JSValue& dataVal = value["data"];
if (dataVal.IsString()) {
return std::make_unique<GeoJSONSource>([&] (Source& base) {
return std::make_unique<Impl>(id, base, std::string(dataVal.GetString(), dataVal.GetStringLength()));
});
} else if (dataVal.IsObject()) {
return std::make_unique<GeoJSONSource>([&] (Source& base) {
return std::make_unique<Impl>(id, base, parseGeoJSON(dataVal));
});
} else {
Log::Error(Event::ParseStyle, "GeoJSON data must be a URL or an object");
return nullptr;
}
}
GeoJSONSource::Impl::Impl(std::string id_, Source& base_, variant<std::string, GeoJSON> urlOrGeoJSON_)
: Source::Impl(SourceType::GeoJSON, std::move(id_), base_),
urlOrGeoJSON(std::move(urlOrGeoJSON_)) {
}
GeoJSONSource::Impl::~Impl() = default;
void GeoJSONSource::Impl::load(FileSource& fileSource) {
if (urlOrGeoJSON.is<GeoJSON>()) {
loaded = true;
return;
}
if (req) {
return;
}
const std::string& url = urlOrGeoJSON.get<std::string>();
req = fileSource.request(Resource::source(url), [this](Response res) {
if (res.error) {
observer->onSourceError(base, std::make_exception_ptr(std::runtime_error(res.error->message)));
} else if (res.notModified) {
return;
} else if (res.noContent) {
observer->onSourceError(base, std::make_exception_ptr(std::runtime_error("unexpectedly empty GeoJSON")));
} else {
rapidjson::GenericDocument<rapidjson::UTF8<>, rapidjson::CrtAllocator> d;
d.Parse<0>(res.data->c_str());
if (d.HasParseError()) {
std::stringstream message;
message << d.GetErrorOffset() << " - " << rapidjson::GetParseError_En(d.GetParseError());
observer->onSourceError(base, std::make_exception_ptr(std::runtime_error(message.str())));
return;
}
invalidateTiles();
urlOrGeoJSON = parseGeoJSON(d);
loaded = true;
observer->onSourceLoaded(base);
}
});
}
Range<uint8_t> GeoJSONSource::Impl::getZoomRange() {
assert(loaded);
return { 0, urlOrGeoJSON.get<GeoJSON>()->options.maxZoom };
}
std::unique_ptr<Tile> GeoJSONSource::Impl::createTile(const OverscaledTileID& tileID,
const UpdateParameters& parameters) {
assert(loaded);
return std::make_unique<GeoJSONTile>(tileID, base.getID(), parameters, *urlOrGeoJSON.get<GeoJSON>());
}
} // namespace style
} // namespace mbgl
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