Static Cache

Description

This module uses the serve-static module to serve cached data.

Installation

Just run in your console:

npm install --save static-cache

How to use

You can simply require the module in node. The required module is a class. You have call the class to make a new object with the folder path for the cache. Additional you can add the maxAge option to set the maxAge of a cached resource.

"use strict";

var Cache = require("static-cache")

var cache = new Cache({path: __dirname+"/_cache", maxAge: 1000*60*60*24}); // maxAge := one day

Please look at the API description for further informations about the cache object.

Example usage

"use strict";

var Cache = require("static-cache")

var cache = new Cache({path: __dirname+"/_cache"});
cache.cache("/path/to/file.txt",                    //the absolute path in cache not in the filesystem!
  "This is the content of the cached file",
  function(err){
    if(err) return console.log("The following error occurred:", err);
    cache.get("/path/to/file.txt", function(err, data){
      if(err) return console.log("The following error occurred:", err);
      console.log("The cached data is: ", data.toString());
      cache.clean("/path/to/file.txt", function(err){
        if(err) return console.log("The following error occurred:", err);
        console.log("'/path/to/file.txt' is deleted");
      });
    });
  });
  
cache.cache("/just/10/seconds.txt", "this file only exists for 10 seconds because of the ttl option", function(err){
  if(err) return console.log("The following error occurred:", err);
  cache.ttl("/just/10/seconds.txt", 1000*10);
  cache.get("/just/10/seconds.txt", function(err, data){
    if(err) return console.log("The following error occurred:", err);
    console.log("The cached data is currently available: ", data.toString());
  });
  
  setTimeout(function(){
    cache.get("/just/10/seconds.txt", function(err, data){
      if(err) return console.log("The resource is already deleted and now we got this error: ", err);
      console.log("The cached data is currently available, but shouldn't: ", data.toString());
    });
  }, 1000*11);
  
});

API

cache(path, content, callback)

Use this for adding contents to the cache. The callback will return nothing or an error, if there is one.

clean(path, callback)

Use this for removing content. Path is optional and matches also on a folder. In this case the whole folder would be deleted. If there is no path specified the whole cache will be deleted.

ttl(path, duration)

This function calls clean(path) after the specified duration. You are able to cache a resource only for a specified duration.

get(path, callback)

Get the content of a saved resource as a stream. The callback will receive cb(err, stream).

serve(req, res, next)

Use this method as a middleware for connect or express.

app = require("express")();
app.use(cache.serve)