Commit 1382ec47 authored by John Crepezzi's avatar John Crepezzi
Browse files

DRY up the static cache

parent 83cb68ad

TODO

+0 −1
Original line number Diff line number Diff line
@@ -5,7 +5,6 @@ add feedback for errors to UI - esp. too long 
add about page

make asset caching optional

todo store buffer instead of string while grabbing contents (if possible)

write cache to use callback instead of using non-DRY code



# shared version only

some way to do announcements easily (and use for ads)

lib/static_handler.js

+34 −24
Original line number Diff line number Diff line
@@ -35,40 +35,50 @@ StaticHandler.prototype.handle = function(incPath, response) { 
  // Go to index if not found or /

  if (!this.availablePaths[incPath]) incPath = this.defaultPath;

  var filePath = this.basePath + (incPath == '/' ? this.defaultPath : incPath);

  // And then stream the file back

  if (StaticHandler.cache[filePath]) {

    this.serveCached(filePath, response);

  // And then stream the file back - either from the cache or from source

  var cached = this.isCached(filePath);

  var method = cached ? this.serveCached : this.retrieve;

  // Run!

  method(filePath, function(error, content) {

    // Get the content

    if (content) {

      var contentType = StaticHandler.contentTypeFor(path.extname(filePath));

      response.writeHead(200, { 'content-type': contentType });

      response.end(content, 'utf-8');

      // Stick it in the cache if its not in there

      if (!cached) {

        StaticHandler.cache[filePath] = content;

      }

    }

    // Or break down and cry

    else {

    this.retrieve(filePath, response);

      winston.error('unable to read file', { path: filePath, error: error });

      response.writeHead(500, { 'content-type': 'application/json' });

      response.end(JSON.stringify({ message: 'IO: Unable to read file' }));

      // If it was cached, bust the cache

      if (cached) {

        StaticHandler.cache[filePath] = null;

      }

    }

  }); 

};



// Retrieve from the file

StaticHandler.prototype.retrieve = function(filePath, response) {

StaticHandler.prototype.retrieve = function(filePath, callback) {

  var _this = this;

  fs.readFile(filePath, function(error, content) {

    if (error) {

      winston.error('unable to read file', { path: filePath, error: error.message });

      response.writeHead(500, { 'content-type': 'application/json' });

      response.end(JSON.stringify({ message: 'IO: Unable to read file' }));

    }

    else {

      var contentType = StaticHandler.contentTypeFor(path.extname(filePath));

      response.writeHead(200, { 'content-type': contentType });

      response.end(content, 'utf-8');

      // Stick it in the cache

      StaticHandler.cache[filePath] = content;

    }

    callback(error, content);

  });    

};



// Retrieve from memory cache

StaticHandler.prototype.serveCached = function(filePath, response) {

  var contentType = StaticHandler.contentTypeFor(path.extname(filePath));

  response.writeHead(200, { 'content-type': contentType });

  response.end(StaticHandler.cache[filePath], 'utf-8');

StaticHandler.prototype.serveCached = function(filePath, callback) {

  callback(undefined, StaticHandler.cache[filePath]);

};



// Determine if a given filePath is cached or not

StaticHandler.prototype.isCached = function(filePath) {

  return !!StaticHandler.cache[filePath];

};



module.exports = StaticHandler;