add imagecleaner, fix #4

modules/clean_images.js

@@ -0,0 +1,44 @@
+var logging = require("./logging");
+var config = require("./config");
+var df = require("node-df");
+var fs = require("fs");
+
+var exp = {};
+
+// uses `df` to get the available fisk space
+// callback contains error, true|false
+function should_clean(callback) {
+  df({
+    file: __dirname + "/../" + config.faces_dir,
+    prefixMultiplier: 'KiB',
+    isDisplayPrefixMultiplier: false,
+    precision: 2
+  }, function (err, response) {
+    var available = response[0].available;
+    console.log("ImageCleaner: " + available + "KB available");
+    callback(err, available < config.cleaning_limit);
+  });
+}
+
+// check if disk limit reached
+// then delete images
+exp.run = function() {
+  should_clean(function(err, clean) {
+    if (err) {
+      logging.error(err);
+    } else if (clean) {
+      logging.warn("ImageCleaner: Disk limit reached! Cleaning images now");
+      var skindir = __dirname + "/../" + config.faces_dir;
+      var helmdir = __dirname + "/../" + config.helms_dir;
+      var files = fs.readdirSync(skindir);
+      for (var i = 0; i < Math.min(files.length, config.cleaning_amount); i++) {
+        fs.unlink(skindir + files[i], function(){});
+        fs.unlink(helmdir + files[i], function(){});
+      }
+    } else {
+      logging.log("ImageCleaner: Nothing to clean");
+    }
+  });
+};
+
+module.exports = exp;

modules/config.example.js

@@ -4,6 +4,9 @@ var config = {
   default_size: 160,         // size to be used when no size given
   local_cache_time: 3600,    // seconds until we will check if the image changed. should be > 60 to prevent mojang 429 response
   browser_cache_time: 3600,  // seconds until browser will request image again
+  cleaning_interval: 1800,   // seconds interval: deleting images if disk size at limit
+  cleaning_limit: 10240,     // minumum required available KB on disk to trigger cleaning
+  cleaning_amount: 50000,    // amount of avatar (and their helm) files to clean
   http_timeout: 1000,        // ms until connection to mojang is dropped
   faces_dir: "skins/faces/", // directory where faces are kept. should have trailing "/"
   helms_dir: "skins/helms/", // directory where helms are kept. should have trailing "/"

modules/config.js

@@ -5,6 +5,9 @@ var config = {
   local_cache_time: 30,      // seconds until we will check if the image changed. should be > 60 to prevent mojang 429 response
   browser_cache_time: 30,    // seconds until browser will request image again
   http_timeout: 3000,        // ms until connection to mojang is dropped
+  cleaning_interval: 3000,      // ms interval: deleting images if disk size at limit
+  cleaning_limit: 10240,     // minumum required available KB on disk to trigger cleaning
+  cleaning_amount: 50000,    // amount of avatar (and their helm) files to clean
   faces_dir: "skins/faces/", // directory where faces are kept. should have trailing "/"
   helms_dir: "skins/helms/", // directory where helms are kept. should have trailing "/"
   debug_enabled: true        // enables logging.debug