tileserver-gl/src/serve_raster.js

302 lines
9.2 KiB
JavaScript

'use strict';
var async = require('async'),
advancedPool = require('advanced-pool'),
crypto = require('crypto'),
fs = require('fs'),
path = require('path'),
util = require('util'),
zlib = require('zlib');
var clone = require('clone'),
express = require('express'),
mercator = new (require('sphericalmercator'))(),
mbgl = require('mapbox-gl-native'),
mbtiles = require('mbtiles'),
request = require('request'),
sharp = require('sharp');
var utils = require('./utils');
var FLOAT_PATTERN = '[+-]?(?:\\d+|\\d+\.?\\d+)';
var SCALE_PATTERN = '@[23]x';
var getScale = function(scale) {
return (scale || '@1x').slice(1, 2) | 0;
};
mbgl.on('message', function(e) {
if (e.severity == 'WARNING' || e.severity == 'ERROR') {
console.log('mbgl:', e);
}
});
module.exports = function(maps, options, prefix) {
var app = express().disable('x-powered-by'),
domains = options.domains,
tilePath = '/{z}/{x}/{y}.{format}';
var rootPath = path.join(process.cwd(), options.root || '');
var styleUrl = options.style;
var map = {
renderers: [],
sources: {},
tileJSON: {}
};
var styleJSON;
var createPool = function(ratio, min, max) {
var createRenderer = function(ratio, createCallback) {
var renderer = new mbgl.Map({
ratio: ratio,
request: function(req, callback) {
var protocol = req.url.split(':')[0];
//console.log('Handling request:', req);
if (protocol == req.url) {
fs.readFile(path.join(rootPath, unescape(req.url)), function(err, data) {
callback(err, { data: data });
});
} else if (protocol == 'mbtiles') {
var parts = req.url.split('/');
var source = map.sources[parts[2]];
var z = parts[3] | 0,
x = parts[4] | 0,
y = parts[5].split('.')[0] | 0;
source.getTile(z, x, y, function(err, data, headers) {
if (err) {
//console.log('MBTiles error, serving empty', err);
callback(null, { data: new Buffer(0) });
} else {
var response = {};
if (headers['Last-Modified']) {
response.modified = new Date(headers['Last-Modified']);
}
if (headers['ETag']) {
response.etag = headers['ETag'];
}
response.data = zlib.unzipSync(data);
callback(null, response);
}
});
} else if (protocol == 'http' || protocol == 'https') {
request({
url: req.url,
encoding: null,
gzip: true
}, function(err, res, body) {
if (err) {
//console.log('HTTP tile error', err);
callback(null, { data: new Buffer(0) });
} else if (res.statusCode == 200) {
var response = {};
if (res.headers.modified) {
response.modified = new Date(res.headers.modified);
}
if (res.headers.expires) {
response.expires = new Date(res.headers.expires);
}
if (res.headers.etag) {
response.etag = res.headers.etag;
}
response.data = body;
callback(null, response);
} else {
//console.log('HTTP error', JSON.parse(body).message);
callback(null, { data: new Buffer(0) });
}
});
}
}
});
renderer.load(styleJSON);
createCallback(null, renderer);
};
return new advancedPool.Pool({
min: min,
max: max,
create: createRenderer.bind(null, ratio),
destroy: function(renderer) {
renderer.release();
}
});
};
styleJSON = require(path.join(rootPath, styleUrl));
map.tileJSON = {
'tilejson': '2.0.0',
'name': styleJSON.name,
'basename': prefix.substr(1),
'minzoom': 0,
'maxzoom': 20,
'bounds': [-180, -85.0511, 180, 85.0511],
'format': 'png',
'type': 'baselayer'
};
Object.assign(map.tileJSON, options.options || {});
var queue = [];
Object.keys(styleJSON.sources).forEach(function(name) {
var source = styleJSON.sources[name];
var url = source.url;
if (url.lastIndexOf('mbtiles:', 0) === 0) {
// found mbtiles source, replace with info from local file
delete source.url;
queue.push(function(callback) {
var mbtilesUrl = url.substring('mbtiles://'.length);
map.sources[name] = new mbtiles(path.join(rootPath, mbtilesUrl), function(err) {
map.sources[name].getInfo(function(err, info) {
Object.assign(source, info);
source.basename = name;
source.tiles = [
// meta url which will be detected when requested
'mbtiles://' + name + tilePath.replace('{format}', 'pbf')
];
callback(null);
});
});
});
}
});
async.parallel(queue, function(err, results) {
// TODO: make pool sizes configurable
map.renderers[1] = createPool(1, 4, 16);
map.renderers[2] = createPool(2, 2, 8);
map.renderers[3] = createPool(3, 2, 4);
});
maps[prefix] = map;
var tilePattern = tilePath
.replace(/\.(?!.*\.)/, ':scale(' + SCALE_PATTERN + ')?.')
.replace(/\./g, '\.')
.replace('{z}', ':z(\\d+)')
.replace('{x}', ':x(\\d+)')
.replace('{y}', ':y(\\d+)')
.replace('{format}', ':format([\\w\\.]+)');
var respondImage = function(z, lon, lat, width, height, scale, format, res, next) {
if (format == 'png' || format == 'webp') {
} else if (format == 'jpg' || format == 'jpeg') {
format = 'jpeg';
} else {
return res.status(404).send('Invalid format');
}
var pool = map.renderers[scale];
pool.acquire(function(err, renderer) {
var mbglZ = Math.max(0, z - 1);
var params = {
zoom: mbglZ,
center: [lon, lat],
width: width,
height: height
};
if (z == 0) {
params.width *= 2;
params.height *= 2;
}
renderer.render(params, function(err, data) {
pool.release(renderer);
if (err) console.log(err);
var image = sharp(data, {
raw: {
width: params.width * scale,
height: params.height * scale,
channels: 4
}
});
if (z == 0) {
// HACK: when serving zoom 0, resize the 0 tile from 512 to 256
image.resize(width * scale, height * scale);
}
image.toFormat(format)
.compressionLevel(9)
.toBuffer(function(err, buffer, info) {
if (!buffer) {
return res.status(404).send('Not found');
}
var md5 = crypto.createHash('md5').update(buffer).digest('base64');
res.set({
'content-md5': md5,
'content-type': 'image/' + format
});
return res.status(200).send(buffer);
});
});
});
};
app.get(tilePattern, function(req, res, next) {
var z = req.params.z | 0,
x = req.params.x | 0,
y = req.params.y | 0,
scale = getScale(req.params.scale),
format = req.params.format;
var tileSize = 256;
var tileCenter = mercator.ll([
((x + 0.5) / (1 << z)) * (256 << z),
((y + 0.5) / (1 << z)) * (256 << z)
], z);
return respondImage(z, tileCenter[0], tileCenter[1], tileSize, tileSize,
scale, format, res, next);
});
var staticPattern =
'/static/%s:scale(' + SCALE_PATTERN + ')?\.:format([\\w\\.]+)';
var centerPattern =
util.format(':lon(%s),:lat(%s),:z(\\d+)/:width(\\d+)x:height(\\d+)',
FLOAT_PATTERN, FLOAT_PATTERN);
app.get(util.format(staticPattern, centerPattern), function(req, res, next) {
var z = req.params.z | 0,
x = +req.params.lon,
y = +req.params.lat,
w = req.params.width | 0,
h = req.params.height | 0,
scale = getScale(req.params.scale),
format = req.params.format;
return respondImage(z, x, y, w, h, scale, format, res, next);
});
var boundsPattern =
util.format(':minx(%s),:miny(%s),:maxx(%s),:maxy(%s)/:z(\\d+)',
FLOAT_PATTERN, FLOAT_PATTERN, FLOAT_PATTERN, FLOAT_PATTERN);
app.get(util.format(staticPattern, boundsPattern), function(req, res, next) {
var z = req.params.z | 0,
x = ((+req.params.minx) + (+req.params.maxx)) / 2,
y = ((+req.params.miny) + (+req.params.maxy)) / 2,
w = req.params.width | 0,
h = req.params.height | 0,
scale = getScale(req.params.scale),
format = req.params.format;
return respondImage(z, x, y, w, h, scale, format, res, next);
});
app.get('/index.json', function(req, res, next) {
var info = clone(map.tileJSON);
info.tiles = utils.getTileUrls(req.protocol, domains, req.headers.host,
prefix, tilePath, info.format,
req.query.key);
return res.send(info);
});
return app;
};