cartodb4/Windshaft-cartodb
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

included LRU cache with redis invalidation

Browse Source
This commit is contained in:
javi santana
2011-10-13 13:17:00 +02:00
parent a211d3c296
commit c1ba45cf5a
10 changed files with 682 additions and 48 deletions
Download Patch File Download Diff File Expand all files Collapse all files
.gitignore
+1
View File
@@ -0,0 +1 @@
node_modules
app.js
+4 -41
View File
@@ -18,7 +18,8 @@ if (ENV != 'development' && ENV != 'production'){
var _ = require('underscore')
, Step = require('step')
, cartoData = require('./lib/cartodb/carto_data');
, cartoData = require('./lib/cartodb/carto_data')
, CartodbWindshaft = require('./lib/cartodb/cartodb_windshaft');
@@ -29,47 +30,9 @@ _.extend(global.settings, global.environment);
var Windshaft = require('windshaft');
var serverOptions = require('./lib/cartodb/server_options');
var Cache = require('./lib/cartodb/tile_cache');
// boot
var ws = new Windshaft.Server(serverOptions);
/**
* Helper to allow access to the layer to be used in the maps infowindow popup.
*/
ws.get(serverOptions.base_url + '/infowindow', function(req, res){
Step(
function(){
serverOptions.getInfowindow(req, this);
},
function(err, data){
if (err){
res.send(err.message, 400);
} else {
res.send({infowindow: data}, 200);
}
}
);
});
/**
* Helper to allow access to metadata to be used in embedded maps.
*/
ws.get(serverOptions.base_url + '/map_metadata', function(req, res){
Step(
function(){
serverOptions.getMapMetadata(req, this);
},
function(err, data){
if (err){
res.send(err.message, 400);
} else {
res.send({map_metadata: data}, 200);
}
}
);
});
ws = CartodbWindshaft(serverOptions);
ws.listen(global.environment.windshaft_port);
console.log("Windshaft tileserver started on port " + global.environment.windshaft_port);
lib/cartodb/cache_validator.js
+76
View File
@@ -0,0 +1,76 @@
//
// this module allows to invalidate cache for a table or check if the cache for a table
// is valid
//
// usage:
//
// Cache.getTimestamp('table_name', function(err, timestamp) {
// });
//
// Cache.setTimestamp('table_name', timestamp, function(err, result) {
// });
//
//
var _ = require('underscore'),
RedisPool = require('./redis_pool'),
Step = require('step')
function Cache(redis_opts) {
var redis_pool = new RedisPool(redis_opts);
var me = {}
var redis_options = {
db: 0
}
var redisCommand = function(fn, callback) {
var redis_client;
Step(
function getRedisClient(){
redis_pool.acquire(redis_options.db, this);
},
function getDataForTable(err, redis) {
if (err) throw err;
redis_client = redis;
fn(redis_client, this);
},
function exit(err, data) {
if (!_.isUndefined(redis_client))
redis_pool.release(redis_options.db, redis_client);
if (callback) {
callback(err, data);
}
}
);
}
// get the timestamp for the table
me.getTimestamp = function(database, table, callback) {
redisCommand(function(redis, step) {
redis.GET("cache:" + database + ":" + table + ":last_updated_at", step);
}, function(err, t) {
if(t != null)
callback(err, parseFloat(t));
else
callback(err, t);
});
}
me.setTimestamp = function(database, table, timestamp, callback) {
timestamp = timestamp || new Date().getTime();
redisCommand(function(redis, step) {
redis.SET("cache:" + database + ":" + table + ":last_updated_at", timestamp, step);
}, callback);
}
return me;
};
module.exports = function(redis_opts) {
return new Cache(redis_opts);
}
lib/cartodb/carto_data.js
+1 -1
View File
@@ -203,4 +203,4 @@ module.exports = function() {
};
return me;
}();
}();
lib/cartodb/cartodb_windshaft.js
+73
View File
@@ -0,0 +1,73 @@
var _ = require('underscore')
, Step = require('step')
, Windshaft = require('windshaft')
, Cache = require('./tile_cache');
var CartodbWindshaft = function(serverOptions) {
// set cache if requested
if(serverOptions.lru_cache) {
var lru_cache = Cache.LRUcache(serverOptions.lru_cache_size || 10000, serverOptions.redis);
_.extend(serverOptions, {
beforeTileRender: lru_cache.beforeTileRender,
afterTileRender: lru_cache.afterTileRender,
cacheStats: lru_cache.getStats,
afterStateChange: lru_cache.afterStateChange
})
}
// boot
var ws = new Windshaft.Server(serverOptions);
/**
* Helper to allow access to the layer to be used in the maps infowindow popup.
*/
ws.get(serverOptions.base_url + '/infowindow', function(req, res){
Step(
function(){
serverOptions.getInfowindow(req, this);
},
function(err, data){
if (err){
res.send(err.message, 400);
} else {
res.send({infowindow: data}, 200);
}
}
);
});
/**
* Helper to allow access to metadata to be used in embedded maps.
*/
ws.get(serverOptions.base_url + '/map_metadata', function(req, res){
Step(
function(){
serverOptions.getMapMetadata(req, this);
},
function(err, data){
if (err){
res.send(err.message, 400);
} else {
res.send({map_metadata: data}, 200);
}
}
);
});
/**
* tile cache stats
*/
ws.get('/cache', function(req, res){
if(serverOptions.cacheStats) {
res.send(serverOptions.cacheStats());
} else {
res.send("Cache no enabled")
}
});
return ws;
}
module.exports = CartodbWindshaft;
lib/cartodb/lru.js
+249
View File
@@ -0,0 +1,249 @@
/**
* see original file: https://github.com/rsms/js-lru
*
* A doubly linked list-based Least Recently Used (LRU) cache. Will keep most
* recently used items while discarding least recently used items when its limit
* is reached.
*
* Licensed under MIT. Copyright (c) 2010 Rasmus Andersson <http://hunch.se/>
* See README.md for details.
*
* Illustration of the design:
*
* entry entry entry entry
* ______ ______ ______ ______
* | head |.newer => | |.newer => | |.newer => | tail |
* | A | | B | | C | | D |
* |______| <= older.|______| <= older.|______| <= older.|______|
*
* removed <-- <-- <-- <-- <-- <-- <-- <-- <-- <-- <-- added
*/
function LRUCache (limit) {
// Current size of the cache. (Read-only).
this.size = 0;
// Maximum number of items this cache can hold.
this.limit = limit;
this._keymap = {};
}
/**
* Put <value> into the cache associated with <key>. Returns the entry which was
* removed to make room for the new entry. Otherwise undefined is returned
* (i.e. if there was enough room already).
*/
LRUCache.prototype.put = function(key, value) {
var entry = {key:key, value:value};
// Note: No protection agains replacing, and thus orphan entries. By design.
this._keymap[key] = entry;
if (this.tail) {
// link previous tail to the new tail (entry)
this.tail.newer = entry;
entry.older = this.tail;
} else {
// we're first in -- yay
this.head = entry;
}
// add new entry to the end of the linked list -- it's now the freshest entry.
this.tail = entry;
if (this.size === this.limit) {
// we hit the limit -- remove the head
return this.shift();
} else {
// increase the size counter
this.size++;
}
}
/**
* Purge the least recently used (oldest) entry from the cache. Returns the
* removed entry or undefined if the cache was empty.
*
* If you need to perform any form of finalization of purged items, this is a
* good place to do it. Simply override/replace this function:
*
* var c = new LRUCache(123);
* c.shift = function() {
* var entry = LRUCache.prototype.shift.call(this);
* doSomethingWith(entry);
* return entry;
* }
*/
LRUCache.prototype.shift = function() {
// todo: handle special case when limit == 1
var entry = this.head;
if (entry) {
if (this.head.newer) {
this.head = this.head.newer;
this.head.older = undefined;
} else {
this.head = undefined;
}
// Remove last strong reference to <entry> and remove links from the purged
// entry being returned:
entry.newer = entry.older = undefined;
// delete is slow, but we need to do this to avoid uncontrollable growth:
delete this._keymap[entry.key];
}
return entry;
}
/**
* Get and register recent use of <key>. Returns the value associated with <key>
* or undefined if not in cache.
*/
LRUCache.prototype.get = function(key, returnEntry) {
// First, find our cache entry
var entry = this._keymap[key];
if (entry === undefined) return; // Not cached. Sorry.
// As <key> was found in the cache, register it as being requested recently
if (entry === this.tail) {
// Already the most recenlty used entry, so no need to update the list
return entry.value;
}
// HEAD--------------TAIL
// <.older .newer>
// <--- add direction --
// A B C <D> E
if (entry.newer) {
if (entry === this.head)
this.head = entry.newer;
entry.newer.older = entry.older; // C <-- E.
}
if (entry.older)
entry.older.newer = entry.newer; // C. --> E
entry.newer = undefined; // D --x
entry.older = this.tail; // D. --> E
if (this.tail)
this.tail.newer = entry; // E. <-- D
this.tail = entry;
return returnEntry ? entry : entry.value;
}
// ----------------------------------------------------------------------------
// Following code is optional and can be removed without breaking the core
// functionality.
/**
* Check if <key> is in the cache without registering recent use. Feasible if
* you do not want to chage the state of the cache, but only "peek" at it.
* Returns the entry associated with <key> if found, or undefined if not found.
*/
LRUCache.prototype.find = function(key) {
return this._keymap[key];
}
/**
* Update the value of entry with <key>. Returns the old value, or undefined if
* entry was not in the cache.
*/
LRUCache.prototype.set = function(key, value) {
var oldvalue, entry = this.get(key, true);
if (entry) {
oldvalue = entry.value;
entry.value = value;
} else {
oldvalue = this.put(key, value);
if (oldvalue) oldvalue = oldvalue.value;
}
return oldvalue;
}
/**
* Remove entry <key> from cache and return its value. Returns undefined if not
* found.
*/
LRUCache.prototype.remove = function(key) {
var entry = this._keymap[key];
if (!entry) return;
delete this._keymap[entry.key]; // need to do delete unfortunately
if (entry.newer && entry.older) {
// relink the older entry with the newer entry
entry.older.newer = entry.newer;
entry.newer.older = entry.older;
} else if (entry.newer) {
// remove the link to us
entry.newer.older = undefined;
// link the newer entry to head
this.head = entry.newer;
} else if (entry.older) {
// remove the link to us
entry.older.newer = undefined;
// link the newer entry to head
this.tail = entry.older;
}
return entry.value;
}
/** Removes all entries */
LRUCache.prototype.removeAll = function() {
// This should be safe, as we never expose strong refrences to the outside
this.head = this.tail = undefined;
this.size = 0;
this._keymap = {};
}
/**
* Return an array containing all keys of entries stored in the cache object, in
* arbitrary order.
*/
if (typeof Object.keys === 'function') {
LRUCache.prototype.keys = function() { return Object.keys(this._keymap); }
} else {
LRUCache.prototype.keys = function() {
var keys = [];
for (var k in this._keymap) keys.push(k);
return keys;
}
}
/**
* Call `fun` for each entry. Starting with the newest entry if `desc` is a true
* value, otherwise starts with the oldest (head) enrty and moves towards the
* tail.
*
* `fun` is called with 3 arguments in the context `context`:
* `fun.call(context, Object key, Object value, LRUCache self)`
*/
LRUCache.prototype.forEach = function(fun, context, desc) {
if (context === true) { desc = true; context = undefined; }
else if (typeof context !== 'object') context = this;
if (desc) {
var entry = this.tail;
while (entry) {
fun.call(context, entry.key, entry.value, this);
entry = entry.older;
}
} else {
var entry = this.head;
while (entry) {
fun.call(context, entry.key, entry.value, this);
entry = entry.newer;
}
}
}
/** Returns a JSON (array) representation */
LRUCache.prototype.toJSON = function() {
var s = [], entry = this.head;
while (entry) {
s.push({key:entry.key.toJSON(), value:entry.value.toJSON()});
entry = entry.newer;
}
return s;
}
/** Returns a String representation */
LRUCache.prototype.toString = function() {
var s = '', entry = this.head;
while (entry) {
s += String(entry.key)+':'+entry.value;
if (entry = entry.newer)
s += ' < ';
}
return s;
}
// Export ourselves
//if (typeof this === 'object') this.LRUCache = LRUCache;
module.exports = LRUCache;
lib/cartodb/tile_cache.js
+111
View File
@@ -0,0 +1,111 @@
// tile cache policies
// it exports two cache types:
// 'nocache' implements a pass-troguth cache
// 'lru' implements a LRU cache
var LRUCache = require('./lru'),
CacheValidator = require('./cache_validator')
module.exports.NoCache = function() {
var me = {}
me.beforeTileRender = function(req, res, callback) {
callback(null);
}
me.afterTileRender = function(req, res, tile, headers, callback) {
callback(null, tile, headers);
}
return me;
}
module.exports.LRUcache = function(max_items, redis_opts) {
var cache_validator = CacheValidator(redis_opts);
return GenericCache(new LRUCache(max_items), cache_validator);
}
// implements a generic cache for tile
// cache_policy should implement set and get methods and optionally getStats
function GenericCache (cache_policy, cache_validator) {
var me = {
cache: cache_policy,
cache_validator: cache_validator,
cache_hits: 0,
cache_misses: 0,
current_items: 0,
cache_invalidated: 0,
max_items: 0
}
function cache_key(req) {
return req.url;
}
function update_items(n) {
me.current_items = n;
if(n > me.max_items) {
me.max_items = n;
}
}
me.beforeTileRender = function(req, res, callback) {
var key = cache_key(req);
var tile = me.cache.get(key);
if(tile) {
// validate the cache
me.cache_validator.getTimestamp(req.params.dbname, req.params.table, function(err, t) {
if(t != null && tile.timestamp < t) {
me.cache_misses++;
me.cache_invalidated++;
callback(null);
} else {
me.cache_hits++;
res.header('X-Cache-hit', 'true');
res.send(tile.tile, tile.headers, 200);
}
});
} else {
me.cache_misses++;
callback(null);
}
}
me.afterTileRender = function(req, res, tile, headers, callback) {
var timestamp = new Date().getTime()/1000.0;
me.cache.put(cache_key(req), { tile: tile, headers: headers, timestamp: timestamp});
update_items(me.cache.size || 0);
callback(null, tile, headers);
}
me.afterStateChange = function(req, data, callback) {
console.log("invalidating", req.params.dbname,", ", req.params.table);
me.cache_validator.setTimestamp(req.params.dbname, req.params.table, new Date().getTime()/1000.0, function(err, t) {
callback(err, data);
});
}
me.getStats = function() {
var total = me.cache_hits + me.cache_misses;
var mem = 0;
me.cache.forEach(function(key, value) {
if(value.tile.length !== undefined) {
mem += value.tile.length;
}
});
return {
cache_hits: me.cache_hits,
cache_misses: me.cache_misses,
current_items: me.current_items,
max_items: me.max_items,
memory: mem,
memory_per_item: total ? mem/total: 0,
ratio: total ? me.cache_hits/total: 0
};
}
return me;
}
test/acceptance/cache.js
+138
View File
@@ -0,0 +1,138 @@
var assert = require('assert')
, tests = module.exports = {}
, _ = require('underscore')
, querystring = require('querystring')
, fs = require('fs')
, th = require(__dirname + '/../test_helper')
, CartodbWindshaft = require(__dirname + '/../../lib/cartodb/cartodb_windshaft')
, http = require('http')
, Step = require('step')
, CacheValidator = require(__dirname + '/../../lib/cartodb/cache_validator')
var serverOptions = require(__dirname + '/../../lib/cartodb/server_options');
var cached_server = new CartodbWindshaft(serverOptions);
tests["first time a tile is request should not be cached"] = function() {
assert.response(cached_server, {
url: '/tiles/gadm4/6/31/24.png?geom_type=polygon',
headers: {host: 'vizzuality.localhost.lan'},
method: 'GET'
},{
status: 200
}, function(res) {
assert.ok(res.header('X-Cache-hit') === undefined);
});
}
/*
tests["second time a tile is request should be cached"] = function() {
var cached_server2 = new CartodbWindshaft(serverOptions);
var url= '/tiles/gadm4/6/31/24.png';
assert.response(cached_server2, {
url: url,
headers: {host: 'vizzuality.localhost.lan'},
method: 'GET'
},{
status: 200
}, function(res) {
assert.response(cached_server2, {
url: url,
headers: {host: 'vizzuality.localhost.lan'},
method: 'GET'
},{
status: 200
}, function(res) {
assert.ok(res.header('X-Cache-hit') !== undefined);
});
});
}
*/
tests["LRU tile should be removed"] = function() {
var urls = ['/tiles/gadm4/6/31/24.png',
'/tiles/gadm4/6/31/25.png',
'/tiles/gadm4/6/31/26.png',
'/tiles/gadm4/6/31/27.png'];
//create another server to not take previos test stats into account
var so = _.clone(serverOptions);
_(so).extend({lru_cache: true, lru_cache_size: 3});
var _cached_server = new CartodbWindshaft(so);
function makeReq(url, callback) {
assert.response(_cached_server, {
url: url,
headers: {host: 'vizzuality.localhost.lan'},
method: 'GET'
},{
status: 200
}, callback);
}
Step(
function() {
makeReq(urls[0], this);
},
function() {
makeReq(urls[1], this);
},
function() {
makeReq(urls[2], this);
},
function() {
makeReq(urls[3], this);
}, function() {
assert.response(_cached_server, {
url: urls[0],
headers: {host: 'vizzuality.localhost.lan'},
method: 'GET'
},{
status: 200
}, function(res) {
assert.ok(res.header('X-Cache-hit') === undefined);
var st = so.cacheStats()
assert.eql(st.cache_hits, 0);
assert.eql(st.cache_misses, 5);
assert.eql(st.current_items, 3);
});
}
)
}
tests["cache should be invalidated"] = function() {
var url = '/tiles/gadm4/6/29/27.png';
var cache = CacheValidator(global.environment.redis);
assert.response(cached_server, {
url: url,
headers: {host: 'vizzuality.localhost.lan'},
method: 'GET'
},{
status: 200
}, function(res) {
cache.setTimestamp('cartodb_dev_user_3_db', 'gadm4', (new Date().getTime()/1000.0)+100, function() {
assert.response(cached_server, {
url: url,
headers: {host: 'vizzuality.localhost.lan'},
method: 'GET'
},{
status: 200
}, function(res) {
assert.ok(res.header('X-Cache-hit') === undefined);
});
});
});
}
test/acceptance/cache_validator.js
+24
View File
@@ -0,0 +1,24 @@
var assert = require('assert'),
tests = module.exports = {},
th = require(__dirname + '/../test_helper'),
CacheValidator = require(__dirname + '/../../lib/cartodb/cache_validator')
var cache = CacheValidator(global.environment.redis);
tests["should get the timestamp it sets"] = function() {
var d = new Date().getTime();
cache.setTimestamp('mydatabase', 'mytable', d, function() {
cache.getTimestamp('mydatabase', 'mytable', function(err, t) {
assert.eql(t, d);
})
});
}
tests["should get null when timestamp is not set"] = function() {
var d = new Date().getTime();
cache.getTimestamp('mydatabase', 'mytable2', function(err, t) {
assert.ok(t === null);
})
}
test/acceptance/server.js
+5 -6
View File
@@ -4,9 +4,9 @@ var _ = require('underscore');
var querystring = require('querystring');
require(__dirname + '/../test_helper');
var Windshaft = require(__dirname + '/../../lib/windshaft');
var CartodbWindshaft = require(__dirname + '/../../lib/cartodb/cartodb_windshaft');
var serverOptions = require(__dirname + '/../../lib/cartodb/server_options');
var server = new Windshaft.Server(serverOptions);
var server = new CartodbWindshaft(serverOptions);
tests['true'] = function() {
assert.ok(true);
@@ -41,7 +41,7 @@ tests["post'ing no style returns 400 with errors"] = function(){
method: 'POST'
},{
status: 400,
body: '{"error":"must sent style information"}'
body: '{"error":"must send style information"}'
});
};
@@ -149,8 +149,6 @@ tests["get'ing completed infowindow with callback returns information with callb
});
};
tests["get'ing a tile with default style should return an image"] = function(){
assert.response(server, {
headers: {host: 'vizzuality.localhost.lan'},
@@ -162,6 +160,7 @@ tests["get'ing a tile with default style should return an image"] = function(){
});
};
tests["get'ing a json with default style should return an grid"] = function(){
assert.response(server, {
headers: {host: 'vizzuality.localhost.lan'},
@@ -211,4 +210,4 @@ tests["get'ing a tile with default style and complex sql should return a constra
status: 200,
headers: { 'Content-Type': 'image/png' }
});
};
};