Rainbows!

Rainbows! is a HTTP server for sleepy Rack applications. It is based on Unicorn, but designed to handle applications that expect long request/response times and/or slow clients. For Rack applications not heavily bound by slow external network dependencies, consider Unicorn instead as it simpler and easier to debug.

Rainbows! is for the odd things Unicorn fails at:

* 3rd-party APIs (to services outside your control/LAN)
* OpenID consumers (to providers outside your control/LAN)
* Reverse proxy implementations with editing/censoring (to upstreams outside your control/LAN)
* Comet
* BOSH (with slow clients)
* HTTP server push
* Long polling
* Reverse Ajax

Rainbows may also be used to service slow clients even with fast applications using the Rev concurrency model.

Installation:

You may download the tarball from the Rainbows project page on Rubyforge and run setup.rb after unpacking it:

rubyforge.org/frs/?group_id=8977

You may also install it via Rubygems on Rubyforge:

 gem install rainbows

Usage:

for Rack applications

In APP_ROOT (where config.ru is located), run:

 rainbows

Rainbows! will bind to all interfaces on TCP port 8080 by default.

Configuration File(s)

Rainbows! will look for the config.ru file used by rackup in APP_ROOT.

For deployments, it can use a config file for Unicorn and Rainbows!-specific options specified by the --config-file/-c command-line switch. Rainbows! accepts all options found in Unicorn::Configurator as well as the “Rainbows!” block, so you can have the following in your config file:

 Rainbows! do
 use :Revactor
 worker_connections 400
 end

Features:

• Designed for Rack, the standard for modern Ruby HTTP applications.
• Built on Unicorn, inheriting its process/socket management features such as transparent upgrades and Ruby configuration DSL.
• As with Unicorn, it is able to stream large request bodies off the socket to the application while the client is still uploading. Since Rainbows! can handle slow clients, this feature is more useful than it is with Unicorn.
• Combines heavyweight concurrency (worker processes) with lightweight concurrency (Actors or Threads), allowing CPU/memory/disk to be scaled independently of client connections. Alternative concurrency models (listed in the TODO) will be supported as we find time for them.

What is new in this release:

• This release adds hijacking support for Rack 1.5.x users. See Rack documentation for more information about hijacking. Lin Jen-Shin also provided the -N/--no-default-middleware option. Minor packaging cleanups and new HACKING document.
• There are also some corner-case bugfixes for *Epoll* users (sleepy_penguin, these bugs do not affect EM or Cool.io users) and test suite portability improvements.

What is new in version 4.4.3:

• This release fixes two EventMachine bugfixes from Lin Jen-Shin and Mark J. Titorenko. There are also some minor cleanups.

What is new in version 4.4.2:

• One bugfix allows stream(:keep_open) in Sinatra to work properly.

What is new in version 4.4.1:

• Fiber-based concurrency options avoids negative sleep intervals. Thanks to Lin Jen-Shin for pointing this out.

What is new in version 4.4.0:

• For epoll/Cool.io-based concurrency models, shutdown() is now used to timeout keepalive clients to avoid race conditions.
• Minor documentation improvements were made.

What is new in version 4.3.1:

• This release fixes a potential reentrancy deadlock when using the default logger from the Ruby standard library.

What is new in version 4.3.0:

• The deprecated Rainbows::HttpResponse class is finally gone thanks to Pratik Naik. Logging of errors is more consistent with the changes in unicorn 4.1.0. There are also minor documentation updates. See the unicorn 4.1.0 release notes for more details: http://bogomips.org/unicorn.git/tag/?id=v4.1.0

What is new in version 4.0.0:

• Rainbows! now scales to more than 1024 worker processes without special privileges. To enable this, Rainbows! now depends on Unicorn 4.x and thus raindrops[1].
• client_max_header_size directive is added to limit per-client memory usage in headers.
• An experimental StreamResponseEpoll concurrency option now exists to buffer outgoing responses without any thread-safe dependencies. Unlike the rest of Rainbows! which works fine without nginx, this concurrency option is /only/ supported behind nginx, even more strongly so than Unicorn itself. non-nginx LAN clients are NOT supported for this. This relies on the sleepy_penguin[2] RubyGem (and Linux).
• There are some minor bug fixes and cleanups all around.

What is new in version 3.4.0:

• SIGQUIT (graceful shutdown) now drops idle keepalive clients for the concurrency models where maintaining an idle client is relatively inexpensive: Coolio, CoolioThreadPool, CoolioThreadSpawn, Epoll, EventMachine, XEpoll, XEpollThreadPool, XEpollThreadSpawn.
• Kgio.autopush now works properly for all multi-threaded concurrency models (if you're using :tcp_nopush).
• locale fix for grep
• t0044: increase test reliability
• try_defer: enable documentation
• xepoll_thread_pool/client: improve autopush support
• .gitignore: add tags/TAGS files
• add tests for Kgio autopush on Linux
• add test for SIGQUIT disconnect
• event_machine: disconnect idle clients at on SIGQUIT
• client: use kgio_write across the board
• coolio* + *epoll*: drop keepalive clients on SIGQUIT
• epoll/xepoll: more consistent client implementations
• doc: recommend io_splice 4.1.1 or later

Requirements:

• Ruby