EM-HTTP-Request
Asynchronous HTTP client for Ruby, based on EventMachine runtime.
- Ragel HTTP parser for speed & performance
- Simple interface for single & parallel requests via deferred callbacks
- Automatic gzip & deflate decoding
- Basic-Auth & OAuth support
- Custom timeout support
- Stream response processing
- Proxy support (with SSL Tunneling)
- Auto-follow 3xx redirects with custom max depth
- Bi-directional communication with web-socket services
- Native mocking support and through Webmock
Getting started
gem install em-http-request
irb:0> require 'em-http'
Or checkout screencast / demo of using EM-HTTP-Request.
Libraries & Applications using em-http
- chirpstream - EM client for Twitters Chirpstream API
- RDaneel - Ruby crawler which respects robots.txt
- rsolr-async - An asynchronus connection adapter for RSolr
- PubSubHubbub - Asynchronous PubSubHubbub ruby client
- and many others.. drop me a link if you want yours included!
Simple client example
EventMachine.run {
http = EventMachine::HttpRequest.new('http://127.0.0.1/').get :query => {'keyname' => 'value'}, :timeout => 10
http.callback {
p http.response_header.status
p http.response_header
p http.response
EventMachine.stop
}
}
Multi-request example
Fire and wait for multiple requests to complete via the MultiRequest interface.
EventMachine.run {
multi = EventMachine::MultiRequest.new
# add multiple requests to the multi-handler
multi.add(EventMachine::HttpRequest.new('http://www.google.com/').get)
multi.add(EventMachine::HttpRequest.new('http://www.yahoo.com/').get)
multi.callback {
p multi.responses[:succeeded]
p multi.responses[:failed]
EventMachine.stop
}
}
Basic-Auth example
Full basic author support. For OAuth, check examples/oauth-tweet.rb file.
EventMachine.run {
http = EventMachine::HttpRequest.new('http://www.website.com/').get :head => {'authorization' => ['user', 'pass']}
http.errback { failed }
http.callback {
p http.response_header
EventMachine.stop
}
}
POSTing data example
EventMachine.run {
http1 = EventMachine::HttpRequest.new('http://www.website.com/').post :body => {"key1" => 1, "key2" => [2,3]}
http2 = EventMachine::HttpRequest.new('http://www.website.com/').post :body => "some data"
# ...
}
Streaming body processing
Allows you to consume an HTTP stream of content in real-time. Each time a new piece of content is pushed to the client, it is passed to the stream callback for you to operate on.
EventMachine.run {
http = EventMachine::HttpRequest.new('http://www.website.com/').get
http.stream { |chunk| print chunk }
}
Streaming files from disk
Allows you to efficiently stream a (large) file from disk via EventMachine's FileStream interface.
EventMachine.run {
http = EventMachine::HttpRequest.new('http://www.website.com/').post :file => 'largefile.txt'
http.callback { |chunk| puts "Upload finished!" }
}
Proxy example
Full transparent proxy support with support for SSL tunneling.
EventMachine.run {
http = EventMachine::HttpRequest.new('http://www.website.com/').get :proxy => {
:host => 'www.myproxy.com',
:port => 8080,
:authorization => ['username', 'password'] # authorization is optional
}
Auto-follow 3xx redirects
Specify the max depth of redirects to follow, default is 0.
EventMachine.run {
http = EventMachine::HttpRequest.new('http://www.google.com/').get :redirects => 1
http.callback { p http.last_effective_url }
}
WebSocket example
Bi-directional communication with WebSockets: simply pass in a ws:// resource and the client will negotiate the connection upgrade for you. On successful handshake the callback is invoked, and any incoming messages will be passed to the stream callback. The client can also send data to the server at will by calling the "send" method!
EventMachine.run {
http = EventMachine::HttpRequest.new("ws://yourservice.com/websocket").get :timeout => 0
http.errback { puts "oops" }
http.callback {
puts "WebSocket connected!"
http.send("Hello client")
}
http.stream { |msg|
puts "Recieved: #{msg}"
http.send "Pong: #{msg}"
}
http.disconnect { puts "oops, dropped connection?" }
}