webmachine-ruby is a port of Webmachine, which is written in Erlang. The goal of both projects is to expose interesting parts of the HTTP protocol to your application in a declarative way. This means that you are less concerned with handling requests directly and more with describing the behavior of the resources that make up your application. Webmachine is not a web framework per se, but more of a toolkit for building HTTP-friendly applications. For example, it does not provide a templating engine or a persistence layer; those choices are up to you.
Webmachine has a Rack adapter -- thanks to Jamis Buck -- but when using it, we recommend you ensure that NO middleware is used. The behaviors that are encapsulated in Webmachine could be broken by middlewares that sit above it, and there is no way to detect them at runtime. Caveat implementor. That said, Webmachine should behave properly when given a clear stack.
Webmachine is very young, but it's still easy to construct an application for it!
require 'webmachine'
# Require any of the files that contain your resources here
require 'my_resource'
# Create an application which encompasses routes and configruation
MyApp = Webmachine::Application.new do |app|
app.routes do
# Point all URIs at the MyResource class
add ['*'], MyResource
end
end
# Start the server, binds to port 8080 using WEBrick
MyApp.run
Your resource will look something like this:
class MyResource < Webmachine::Resource
def to_html
"<html><body>Hello, world!</body></html>"
end
end
Run the first file and your application is up. That's all there is to
it! If you want to customize your resource more, look at the available
callbacks in lib/webmachine/resource/callbacks.rb. For example, you
might want to enable "gzip" compression on your resource, for which
you can simply add an encodings_provided
callback method:
class MyResource < Webmachine::Resource
def encodings_provided
{"gzip" => :encode_gzip, "identity" => :encode_identity}
end
def to_html
"<html><body>Hello, world!</body></html>"
end
end
There are many other HTTP features exposed to your resource through {Webmachine::Resource::Callbacks}. Give them a try!
There's a configurator that allows you to set the ip address and port
bindings as well as a different webserver adapter. You can also add
your routes in a block (as shown above). Both of these call return the
Webmachine::Application
instance, so you could chain them if you
like. If you don't want to create your own separate application
object, Webmachine.application
will return a global one.
require 'webmachine'
require 'my_resource'
Webmachine.application.routes do
add ['*'], MyResource
end
Webmachine.application.configure do |config|
config.ip = '127.0.0.1'
config.port = 3000
config.adapter = :Mongrel
end
# Start the server.
Webmachine.application.run
- Handles the hard parts of content negotiation, conditional requests, and response codes for you.
- Most callbacks can interrupt the decision flow by returning an integer response code. You generally only want to do this when new information comes to light, requiring a modification of the response.
- Supports WEBrick and Mongrel (1.2pre+), and a Rack shim. Other host servers are being investigated.
- Streaming/chunked response bodies are permitted as Enumerables, Procs, or Fibers!
- Unlike the Erlang original, it does real Language negotiation.
- Command-line tools, and general polish.
- Tracing is exposed as an Array of decisions visited on the response object. You should be able to turn this off and on, and visualize the decisions on the sequence diagram.
0.4.1 is a bugfix release that corrects a few minor issues. Added Sam Goldman as a contributor. Thank you for your contributions!
- Updated README with
Webmachine::Application
examples. - The CGI env vars
CONTENT_LENGTH
andCONTENT_TYPE
are now being correctly converted into their Webmachine equivalents. - The request body given via the Rack and Mongrel adapters now
responds to
#to_s
and#each
so it can be treated like aString
orEnumerable
that yields chunks.
0.4.0 includes some important refactorings, isolating the idea of global state into an Application object with its own Dispatcher and configuration, and making Adapters into real classes with a consistent interface. It also adds some query methods on the Request object for the HTTP method and scheme and Route guards (matching predicates). Added Michael Maltese, Emmanuel Gomez, and Bernerd Schaefer as committers. Thank you for your contributions!
- Fixed
Request#query
to handle nil values for the URI query accessor. Webmachine::Dispatcher
is a real class rather than a module with state.Webmachine::Application
is a class that includes its own dispatcher and configuration. The default instance is accessible viaWebmachine.application
.Webmachine::Adapter
is now the superclass of all implemented adapters so that they have a uniform interface.- The Mongrel spec is skipped on JRuby since version 1.2 (pre-release) doesn't work. Direct Mongrel support may be removed in a later release.
Webmachine::Dispatcher::Route
now accepts guards, which may be expressed as lambdas/procs or any object responding tocall
preceding theResource
class in the route definition, or as a trailing block. All guards will be passed theRequest
object when matching the route and should return a truthy or falsey value (without side-effects).
0.3.0 introduces some new features, refactorings, and now has 100% documentation coverage! Among the new features are minimal Rack compatibility, streaming responses via Fibers and a friendlier route definition syntax. Added Jamis Buck as a committer. Thank you for your contributions!
- Chunked bodies are now wrapped in a way that works on webservers that don't automatically produce them.
- HTTP Basic Authentication is easy to add to resources, just include
Webmachine::Resource::Authentication
. - Routes are a little less painful to add, you can now specify them
with
Webmachine.routes
which will be evaled into theDispatcher
. - The new default port is 8080.
- Rack is minimally supported as a host server. Don't put middleware above Webmachine!
- Fibers can be used as streamed response bodies.
Dispatcher#add_route
will now return the addedRoute
instance.- The header-conversion code for CGI-style servers has been extracted
into
Webmachine::Headers
. Route#path_spec
is now public so that applications can inspect existing routes, perhaps for URL generation.Request#query
now usesCGI.unescape
so '+' characters are correctly parsed.- YARD documentation has 100% coverage.
0.2.0 includes an adapter for Mongrel and a central place for configuration as well as numerous bugfixes. Added Ian Plosker and Bernd Ahlers as committers. Thank you for your contributions!
- Acceptable media types are matched less strictly, which has implications on both responses and PUT requests. See the discussion on the commit.
- Resources now receive a callback after the language has been negotiated, so they can decide what to do with it.
- Added
Webmachine::Configuration
so we can more easily support more than one host server/adapter. - Added Mongrel adapter, supporting 1.2pre+.
- Media type headers are more lax about whitespace following semicolons.
- Fix some problems with callable response bodies.
- Make sure String response bodies get a Content-Length header added and streaming responses get chunked encoding.
- Numerous refactorings, including extracting
MediaType
into its own top-level class.
This is the initial release. Most things work, but only WEBrick is supported.