Function fetchTraceGeoData

src/lib/geo_location_utils.js:337–391

(calcData)

}

function fetchTraceGeoData(calcData) {
    var PlotlyGeoAssets = window.PlotlyGeoAssets || {};
    var promises = [];

    function fetch(url) {
        return new Promise(function (resolve, reject) {
            d3.json(url, function (err, d) {
                if (err) {
                    delete PlotlyGeoAssets[url];
                    var msg =
                        err.status === 404
                            ? 'GeoJSON at URL "' + url + '" does not exist.'
                            : 'Unexpected error while fetching from ' + url;
                    return reject(new Error(msg));
                }

                PlotlyGeoAssets[url] = d;
                return resolve(d);
            });
        });
    }

    function wait(url) {
        return new Promise(function (resolve, reject) {
            var cnt = 0;
            var interval = setInterval(function () {
                if (PlotlyGeoAssets[url] && PlotlyGeoAssets[url] !== 'pending') {
                    clearInterval(interval);
                    return resolve(PlotlyGeoAssets[url]);
                }
                if (cnt > 100) {
                    clearInterval(interval);
                    return reject('Unexpected error while fetching from ' + url);
                }
                cnt++;
            }, 50);
        });
    }

    for (var i = 0; i < calcData.length; i++) {
        var trace = calcData[i][0].trace;
        var url = trace.geojson;

        if (typeof url === 'string') {
            if (!PlotlyGeoAssets[url]) {
                PlotlyGeoAssets[url] = 'pending';
                promises.push(fetch(url));
            } else if (PlotlyGeoAssets[url] === 'pending') {
                promises.push(wait(url));
            }
        }
    }

    return promises;
}

// TODO `turf/bbox` gives wrong result when the input feature/geometry
// crosses the anti-meridian. We should try to implement our own bbox logic.