Rack::Hard::Copy

This is a simple middleware to save and load static copies of rendered pages. So in other words, this is simple static cache which saves in a format that can be used as a backup, or to be loaded via a simple http server (e.g. Nginx).

Installation

echo "gem 'rack-static-copy'" >> Gemfile
bundle

Usage - Basic

# config.ru
require 'rack/hard/copy'
use Rack::Hard::Copy, :store   => "/tmp/hard_copy",
                      :ignores => [ "search", "js", "png", "gif" ],
                      :timeout => 600

run App

Note: This should probably be the last middleware loaded.

Options

• :store - path to file store
• :ignores - Array of keywords to be ignored
• :timeout - Fixnum as seconds to expire stored files
• :headers - Boolean can be set to true to insert custom http headers
  • X-Rack-Hard-Save => (true|false)
  • X-Rack-Hard-Load => (true|false)

Another Use

Additionally, you can use Rack::Hard::Save alone to simple create a copy of your pages in rendered html format (other formats are supported).

Exmaple:

# config.ru
require 'rack/hard/save'
use Rack::Hard::Save, :store   => "/path/to/nginx/root/static",
                      :ignores => [ "search", "js", "png", "gif" ],
                      :timeout => 600

run App

From there you can use Nginx to first check and see if the static pages exist and if not, load your app normally, which will in turn generate the static content.

Very large speed enhancments should be see doing this.

Nginx example config:

# /etc/nginx/sites-enabled/my_site.conf
server {
    #listen   80; ## listen for ipv4; this line is default and implied
    #listen   [::]:80 default ipv6only=on; ## listen for ipv6

    root /path/to/nginx/root;

    server_name localhost;

    location / {
        try_files /static$uri/index.html /static$uri $uri @app;
    }

    location @app {
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header Host $http_host;
        proxy_pass http://0.0.0.0:8080;
    }
}

The key to above lies in /static$uri/index.html and /static$uri.

Rack::Hard::Copy turns /foo in to /foo/index.html, while simply copying anything with an extension. The above try_files will look for this pattner in your choosen root and store location.

Load

You can also load static files, on your own. This might be good for pregenerating large sitemaps, error pages, etc. Why? Well, it might be nice to dynamically generate a page, sitemaps in particular, but store them staticly to reduce load on your host when they're rather large.

# config.ru
require 'rack/hard/load'
use Rack::Hard::Load, :store   => "./hard_copy",
                      :timeout => false

Pregeneration examples:

$ curl http://yoursite.com/sitemap.xml > ./hard_copy/sitemap.xml
$ curl http://yoursite.com/main.css > ./hard_copy/main.css

These could be automated as part of your startup.