mongotiles

### # # Copyright (C) 2013-2016 by Vaughn Iverson # # mongotiles # # With this you can use MongoDB GridFS as a "tilelive.js" source or sink for # map tile / grid / tilejson data. # # See: https://github.com/mapbox/tilelive.js # # This project is free software released under the MIT/X11 license. # See LICENSE file for more information. # ### path = require 'path' fs = require 'fs' url = require 'url' querystring = require 'querystring' mongodb = require 'mongodb' LockCollection = require('gridfs-locks').LockCollection Lock = require('gridfs-locks').Lock protocol = 'mongotiles' default_root = 'fs' tile_name = (z, x, y) -> if x? and y? and z? name = "tile_#{z}_#{x}_#{y}" else name = 'tile_{z}_{x}_{y}' grid_name = (z, x, y) -> if x? and y? and z? name = "grid_#{z}_#{x}_#{y}" else name = 'grid_{z}_{x}_{y}' tilejson_name = "tilejson.json" # Image type magic numbers snarfed from https://github.com/mapbox/node-tilejson get_mime_type = (bytes) -> if (bytes[0] is 0x89 and bytes[1] is 0x50 and bytes[2] is 0x4E and bytes[3] is 0x47 and bytes[4] is 0x0D and bytes[5] is 0x0A and bytes[6] is 0x1A and bytes[7] is 0x0A) return 'image/png' else if (bytes[0] is 0xFF and bytes[1] is 0xD8 and bytes[bytes.length - 2] is 0xFF and bytes[bytes.length - 1] is 0xD9) return 'image/jpeg' else if (bytes[0] is 0x47 and bytes[1] is 0x49 and bytes[2] is 0x46 and bytes[3] is 0x38 and (bytes[4] is 0x39 or bytes[4] is 0x37) and bytes[5] is 0x61) return 'image/gif' else console.warn "#{protocol}: Image data with unknown MIME type in putTile call to get_mime_type." return 'application/octet-stream' class Tilemongo _file_exists : (fn, cb) -> @files.findOne {filename: fn}, {_id: 1}, (err, doc) => return cb err, doc _write_buffer : (fn, type, buffer, metadata, cb) -> write_it = (_id, l) => gs = new mongodb.GridStore @db, _id, fn, 'w', { w : 1, root : @grid_root, content_type : type, metadata: metadata } gs.open (err, gs) => return cb err if err gs.write buffer, (err, gs) => return cb err if err gs.close (err) => l.releaseLock() if l cb err @_file_exists fn, (err, doc) => return cb err if err unless doc doc = { _id: new mongodb.ObjectID() } if @lockColl lock = Lock(doc._id, @lockColl, {}).obtainWriteLock() lock.on 'timed-out', () => cb new Error "Timed out waiting for write lock" lock.on 'error', (err) => cb err lock.on 'locked', (ld) => write_it doc._id, lock else write_it doc._id _read_buffer : (fn, cb) -> read_it = (_id, l) => gs = new mongodb.GridStore @db, _id, 'r', { root : @grid_root } gs.open (err, gs) => return cb err if err gs.read (err, buffer) => return cb err if err gs.close (err) => l.releaseLock() if l cb err, buffer @_file_exists fn, (err, doc) => return cb err if err unless doc return cb null, null if @lockColl lock = Lock(doc._id, @lockColl, {}).obtainReadLock() lock.on 'timed-out', () => cb new Error "Timed out waiting for write lock" lock.on 'error', (err) => cb err lock.on 'locked', (ld) => read_it doc._id, lock else read_it doc._id @registerProtocols = (tilelive) -> tilelive.protocols["#{protocol}:"] = @ @list = (filepath, callback) -> callback new Error ".list not implemented for #{protocol}" @findID = (filepath, id, callback) -> callback new Error ".findID not implemented for #{protocol}" constructor : (uri, callback) -> @starts = 0 # uri seems to be preparsed, but make sure... if typeof uri is 'string' uri = url.parse uri, true if typeof uri.query is 'string' uri.query = querystring.parse uri.query unless uri.protocol is "#{protocol}:" return callback new Error "Bad uri protocol '#{uri.protocol}'. Must be #{protocol}." tilepath_match = uri.pathname.match new RegExp "(/[^/]+)(/[^/]+)?" unless tilepath_match return callback new Error "Bad tile url path '#{uri.pathname}' for #{uri.protocol}." locking = uri.query?.locking ? false uri.query = '' uri.search = '' uri.hash = '' uri.protocol = 'http:' @source = url.format uri @db_name = tilepath_match[1][1...] @grid_root = tilepath_match[2]?[1...] or default_root uri.path = @db_name uri.pathname = uri.path uri.protocol = 'mongodb:' @server = url.format(uri) console.log "Server: #{@server}" mongodb.MongoClient.connect @server, (err, db) => return callback err if err @db = db console.log "GRID ROOT #{@grid_root}" @db.collection "#{@grid_root}.files", { w: 1 }, (err, coll) => return callback err if err @files = coll unless locking return callback null, @ else @lockColl = LockCollection(@db, root: @grid_root timeOut: 60, pollingInterval: 5, lockExpiration: 30) @lockColl.on 'ready', () => callback null, @ @lockColl.on 'error', (err) -> callback err close : (callback) -> @db.close(callback) getInfo : (callback) -> @_read_buffer tilejson_name, (err, info) => return callback err if err callback null, JSON.parse(info) getTile : (z, x, y, callback) -> tn = tile_name z, x, y @_read_buffer tn, (err, data) => if err callback err else unless data callback new Error('Tile does not exist') else callback null, data getGrid : (z, x, y, callback) -> gn = grid_name z, x, y @_read_buffer gn, (err, data) => if err callback err else unless data callback new Error('Grid does not exist') else callback null, JSON.parse(data) startWriting : (callback) -> @starts += 1 callback null stopWriting : (callback) -> @starts -= 1 callback null putInfo : (info, callback) -> unless @starts return callback new Error "Error, writing not started." tn = tile_name() info.tiles = [ "#{@source}#{tn}" ] if info.grids? gn = grid_name() info.grids = [ "#{@source}#{gn}" ] @_write_buffer tilejson_name, 'application/json', JSON.stringify(info), null, callback putTile : (z, x, y, tile, callback) -> unless @starts return callback new Error "Error, writing not started." tn = tile_name z, x, y type = get_mime_type tile @_write_buffer tn, type, tile, { type: "tile", x:x, y:y, z:z }, callback putGrid : (z, x, y, grid, callback) -> unless @starts return callback new Error "Error, writing not started." gn = grid_name z, x, y @_write_buffer gn, 'application/json', JSON.stringify(grid), { type: "grid", x:x, y:y, z:z }, callback module.exports = Tilemongo