lib/helpers.js
var networking = require("./networking");
var logging = require("./logging");
var renders = require("./renders");
var config = require("../config");
var cache = require("./cache");
var skins = require("./skins");
var path = require("path");
var fs = require("fs");
// 0098cb60fa8e427cb299793cbd302c9a
var valid_user_id = /^[0-9a-fA-F]{32}$/; // uuid
var hash_pattern = /[0-9a-f]+$/;
// gets the hash from the textures.minecraft.net +url+
function get_hash(url) {
return hash_pattern.exec(url)[0].toLowerCase();
}
// gets the skin for +userId+ with +profile+
// uses +cache_details+ to determine if the skin needs to be downloaded or can be taken from cache
// face and face+helm images are extracted and stored to files
// callback: error, skin hash, slim
function store_skin(rid, userId, profile, cache_details, callback) {
networking.get_skin_info(rid, userId, profile, function(err, url, slim) {
if (err) {
slim = cache_details ? cache_details.slim : undefined;
}
if (!err && url) {
var skin_hash = get_hash(url);
if (cache_details && cache_details.skin === skin_hash) {
cache.update_timestamp(rid, userId, false, function(cache_err) {
callback(cache_err, skin_hash, slim);
});
} else {
logging.debug(rid, "new skin hash:", skin_hash);
var facepath = path.join(config.directories.faces, skin_hash + ".png");
var helmpath = path.join(config.directories.helms, skin_hash + ".png");
var skinpath = path.join(config.directories.skins, skin_hash + ".png");
fs.access(facepath, function(fs_err) {
if (!fs_err) {
logging.debug(rid, "skin already exists, not downloading");
callback(null, skin_hash, slim);
} else {
networking.get_from(rid, url, function(img, response, err1) {
if (err1 || !img) {
callback(err1, null, slim);
} else {
skins.save_image(img, skinpath, function(skin_err) {
if (skin_err) {
callback(skin_err, null, slim);
} else {
skins.extract_face(img, facepath, function(err2) {
if (err2) {
callback(err2, null, slim);
} else {
logging.debug(rid, "face extracted");
skins.extract_helm(rid, facepath, img, helmpath, function(err3) {
logging.debug(rid, "helm extracted");
logging.debug(rid, helmpath);
callback(err3, skin_hash, slim);
});
}
});
}
});
}
});
}
});
}
} else {
callback(err, null);
}
});
}
// gets the cape for +userId+ with +profile+
// uses +cache_details+ to determine if the cape needs to be downloaded or can be taken from cache
// the cape - if downloaded - is stored to file
// callback: error, cape hash
function store_cape(rid, userId, profile, cache_details, callback) {
networking.get_cape_url(rid, userId, profile, function(err, url) {
if (!err && url) {
var cape_hash = get_hash(url);
if (cache_details && cache_details.cape === cape_hash) {
cache.update_timestamp(rid, userId, false, function(cache_err) {
callback(cache_err, cape_hash);
});
} else {
logging.debug(rid, "new cape hash:", cape_hash);
var capepath = path.join(config.directories.capes, cape_hash + ".png");
fs.access(capepath, function(fs_err) {
if (!fs_err) {
logging.debug(rid, "cape already exists, not downloading");
callback(null, cape_hash);
} else {
networking.get_from(rid, url, function(img, response, net_err) {
if (net_err || !img) {
callback(net_err, null);
} else {
skins.save_image(img, capepath, function(skin_err) {
logging.debug(rid, "cape saved");
callback(skin_err, cape_hash);
});
}
});
}
});
}
} else {
callback(err, null);
}
});
}
// used by store_images to queue simultaneous requests for identical userId
// the first request has to be completed until all others are continued
// otherwise we risk running into Mojang's rate limit and deleting the cached skin
var requests = {
skin: {},
cape: {}
};
var loginterval = setInterval(function(){
var skinreqs = Object.keys(requests.skin).length;
var capereqs = Object.keys(requests.cape).length;
if (skinreqs || capereqs) {
logging.log("Currently waiting for " + skinreqs + " skin requests and " + capereqs + " cape requests.");
}
}, 1000);
// add a request for +userId+ and +type+ to the queue
function push_request(userId, type, callback) {
// avoid special properties (e.g. 'constructor')
var userId_safe = "!" + userId;
if (!requests[type][userId_safe]) {
requests[type][userId_safe] = [];
}
requests[type][userId_safe].push(callback);
}
// calls back all queued requests that match userId and type
function resume(userId, type, err, hash, slim) {
var userId_safe = "!" + userId;
var callbacks = requests[type][userId_safe];
if (callbacks) {
if (callbacks.length > 1) {
logging.debug(callbacks.length, "simultaneous requests for", userId);
}
for (var i = 0; i < callbacks.length; i++) {
// continue the request
callbacks[i](err, hash, slim);
// remove from array
callbacks.splice(i, 1);
i--;
}
// it's still an empty array
delete requests[type][userId_safe];
}
}
// downloads the images for +userId+ while checking the cache
// status based on +cache_details+. +type+ specifies which
// image type should be called back on
// callback: error, image hash, slim
function store_images(rid, userId, cache_details, type, callback) {
if (requests[type]["!" + userId]) {
logging.debug(rid, "adding to request queue");
push_request(userId, type, callback);
} else {
push_request(userId, type, callback);
networking.get_profile(rid, userId, function(err, profile) {
if (err || !profile) {
// error or uuid without profile
if (!err && !profile) {
// no error, but uuid without profile
cache.save_hash(rid, userId, null, null, undefined, function(cache_err) {
// we have no profile, so we have neither skin nor cape
resume(userId, "skin", cache_err, null, false);
resume(userId, "cape", cache_err, null, false);
});
} else {
// an error occured, not caching. we can try again in 60 seconds
resume(userId, type, err, null, false);
}
} else {
// no error and we have a profile (if it's a uuid)
store_skin(rid, userId, profile, cache_details, function(store_err, skin_hash, slim) {
if (store_err && !skin_hash) {
// an error occured, not caching. we can try in 60 seconds
resume(userId, "skin", store_err, null, slim);
} else {
cache.save_hash(rid, userId, skin_hash, undefined, slim, function(cache_err) {
resume(userId, "skin", (store_err || cache_err), skin_hash, slim);
});
}
});
store_cape(rid, userId, profile, cache_details, function(store_err, cape_hash) {
if (store_err && !cape_hash) {
// an error occured, not caching. we can try in 60 seconds
resume(userId, "cape", (store_err), cape_hash, false);
} else {
cache.save_hash(rid, userId, undefined, cape_hash, undefined, function(cache_err) {
resume(userId, "cape", (store_err || cache_err), cape_hash, false);
});
}
});
}
});
}
}
var exp = {};
// returns true if the +userId+ is a valid userId
// the UUID might not exist, however
exp.id_valid = function(userId) {
return valid_user_id.test(userId);
};
// decides whether to get a +type+ image for +userId+ from disk or to download it
// callback: error, status, hash, slim
// for status, see response.js
exp.get_image_hash = function(rid, userId, type, callback) {
cache.get_details(userId, function(err, cache_details) {
var cached_hash = null;
if (cache_details !== null) {
cached_hash = type === "skin" ? cache_details.skin : cache_details.cape;
}
if (err) {
callback(err, -1, null, false);
} else {
if (cache_details && cache_details[type] !== undefined && cache_details.time + config.caching.local * 1000 >= Date.now()) {
// use cached image
logging.debug(rid, "userId cached & recently updated");
callback(null, (cached_hash ? 1 : 0), cached_hash, cache_details.slim);
} else {
// download image
if (cache_details && cache_details[type] !== undefined) {
logging.debug(rid, "userId cached, but too old");
logging.debug(rid, JSON.stringify(cache_details));
} else {
logging.debug(rid, "userId not cached");
}
store_images(rid, userId, cache_details, type, function(store_err, new_hash, slim) {
if (store_err) {
// an error occured, but we have a cached hash
// (e.g. Mojang servers not reachable, using outdated hash)
// bump the TTL after hitting the rate limit
var ratelimited = store_err.code === "RATELIMIT";
cache.update_timestamp(rid, userId, !ratelimited, function(err2) {
callback(err2 || store_err, 4, cache_details && cached_hash, slim);
});
} else {
var status = cache_details && (cached_hash === new_hash) ? 3 : 2;
logging.debug(rid, "cached hash:", (cache_details && cached_hash));
logging.debug(rid, "new hash:", new_hash);
callback(null, status, new_hash, slim);
}
});
}
}
});
};
// handles requests for +userId+ avatars with +size+
// callback: error, status, image buffer, skin hash
// image is the user's face+overlay when overlay is true, or the face otherwise
// for status, see get_image_hash
exp.get_avatar = function(rid, userId, overlay, size, callback) {
exp.get_image_hash(rid, userId, "skin", function(err, status, skin_hash, slim) {
if (skin_hash) {
var facepath = path.join(config.directories.faces, skin_hash + ".png");
var helmpath = path.join(config.directories.helms, skin_hash + ".png");
var filepath = facepath;
fs.access(helmpath, function(fs_err) {
if (overlay && !fs_err) {
filepath = helmpath;
}
skins.resize_img(filepath, size, function(img_err, image) {
if (img_err) {
callback(img_err, -1, null, skin_hash);
} else {
status = err ? -1 : status;
callback(err, status, image, skin_hash);
}
});
});
} else {
// hash is null when userId has no skin
callback(err, status, null, null);
}
});
};
// handles requests for +userId+ skins
// callback: error, skin hash, status, image buffer, slim
exp.get_skin = function(rid, userId, callback) {
exp.get_image_hash(rid, userId, "skin", function(err, status, skin_hash, slim) {
if (skin_hash) {
var skinpath = path.join(config.directories.skins, skin_hash + ".png");
fs.access(skinpath, function(fs_err) {
if (!fs_err) {
logging.debug(rid, "skin already exists, not downloading");
skins.open_skin(rid, skinpath, function(skin_err, img) {
callback(skin_err || err, skin_hash, status, img, slim);
});
} else {
networking.save_texture(rid, skin_hash, skinpath, function(net_err, response, img) {
callback(net_err || err, skin_hash, status, img, slim);
});
}
});
} else {
callback(err, null, status, null, slim);
}
});
};
// helper method used for file names
// possible returned names based on +overlay+ and +body+ are:
// body, bodyhelm, head, headhelm
function get_type(overlay, body) {
var text = body ? "body" : "head";
return overlay ? text + "helm" : text;
}
// handles creations of 3D renders
// callback: error, status, skin hash, image buffer
exp.get_render = function(rid, userId, scale, overlay, body, callback) {
exp.get_skin(rid, userId, function(err, skin_hash, status, img, slim) {
if (!skin_hash) {
callback(err, status, skin_hash, null);
return;
}
var renderpath = path.join(config.directories.renders, [skin_hash, scale, get_type(overlay, body), slim ? "s" : "t"].join("-") + ".png");
fs.access(renderpath, function(fs_err) {
if (!fs_err) {
renders.open_render(rid, renderpath, function(render_err, rendered_img) {
callback(render_err, 1, skin_hash, rendered_img);
});
return;
} else {
if (!img) {
callback(err, 0, skin_hash, null);
return;
}
renders.draw_model(rid, img, scale, overlay, body, slim || userId.toLowerCase() === "mhf_alex", function(draw_err, drawn_img) {
if (draw_err) {
callback(draw_err, -1, skin_hash, null);
} else if (!drawn_img) {
callback(null, 0, skin_hash, null);
} else {
fs.writeFile(renderpath, drawn_img, "binary", function(write_err) {
callback(write_err, status, skin_hash, drawn_img);
});
}
});
}
});
});
};
// handles requests for +userId+ capes
// callback: error, cape hash, status, image buffer
exp.get_cape = function(rid, userId, callback) {
exp.get_image_hash(rid, userId, "cape", function(err, status, cape_hash, slim) {
if (!cape_hash) {
callback(err, null, status, null);
return;
}
var capepath = path.join(config.directories.capes, cape_hash + ".png");
fs.access(capepath, function(fs_err) {
if (!fs_err) {
logging.debug(rid, "cape already exists, not downloading");
skins.open_skin(rid, capepath, function(skin_err, img) {
callback(skin_err || err, cape_hash, status, img);
});
} else {
networking.save_texture(rid, cape_hash, capepath, function(net_err, response, img) {
if (response && response.statusCode === 404) {
callback(net_err, cape_hash, status, null);
} else {
callback(net_err, cape_hash, status, img);
}
});
}
});
});
};
exp.stoplog = function() {
clearInterval(loginterval);
}
module.exports = exp;