Manual de Ruby:Programación orientada a red
De Foros del Web
En este apartado daremos a conocer las características que le permiten a Ruby trabajar con la capa de red.
NET::HTTP
Esta librería le permite a nuestras aplicaciones tener acceso a paginas de internet utilizando el protocolo HTTP versión 1.1. Para mas detalles del protocolo dirigirse a [RFC2616] (www.ietf.org/rfc/rfc2616.txt).
Ejemplos Descargado Documentos desde un Servidor
- 1: Un sencillo GET+print
require 'net/http' Net::HTTP.get_print 'www.example.com', '/index.html'
- 2: Un sencillo GET+print a través de un URL
require 'net/http'
require 'uri'
Net::HTTP.get_print URI.parse('http://www.example.com/index.html')
- 3: GET+print avanzado
require 'net/http' require 'uri'
url = URI.parse('http://www.example.com/index.html')
res = Net::HTTP.start(url.host, url.port) {|http|
http.get('/index.html')
}
puts res.body
- 4: GET+print aun mas avanzado
require 'net/http'
url = URI.parse('http://www.example.com/index.html')
req = Net::HTTP::Get.new(url.path)
res = Net::HTTP.start(url.host, url.port) {|http|
http.request(req)
}
puts res.body
Posting Form Data
require 'net/http' require 'uri'
#1: Simple POST
res = Net::HTTP.post_form(URI.parse('http://www.example.com/search.cgi'),
{'q'=>'ruby', 'max'=>'50'})
puts res.body
#2: POST with basic authentication
res = Net::HTTP.post_form(URI.parse('http://jack:pass@www.example.com/todo.cgi'),
{'from'=>'2005-01-01', 'to'=>'2005-03-31'})
puts res.body
#3: Detailed control
url = URI.parse('http://www.example.com/todo.cgi')
req = Net::HTTP::Post.new(url.path)
req.basic_auth 'jack', 'pass'
req.set_form_data({'from'=>'2005-01-01', 'to'=>'2005-03-31'}, ';')
res = Net::HTTP.new(url.host, url.port).start {|http| http.request(req) }
case res
when Net::HTTPSuccess, Net::HTTPRedirection
# OK
else
res.error!
end
Accessing via Proxy
Net::HTTP.Proxy creates http proxy class. It has same methods of Net::HTTP but its instances always connect to proxy, instead of given host.
require 'net/http'
proxy_addr = 'your.proxy.host'
proxy_port = 8080
:
Net::HTTP::Proxy(proxy_addr, proxy_port).start('www.example.com') {|http|
# always connect to your.proxy.addr:8080
:
}
Since Net::HTTP.Proxy returns Net::HTTP itself when proxy_addr is nil, there‘s no need to change code if there‘s proxy or not.
There are two additional parameters in Net::HTTP.Proxy which allow to specify proxy user name and password:
Net::HTTP::Proxy(proxy_addr, proxy_port, proxy_user = nil, proxy_pass = nil)
You may use them to work with authorization-enabled proxies:
require 'net/http' require 'uri'
proxy_host = 'your.proxy.host'
proxy_port = 8080
uri = URI.parse(ENV['http_proxy'])
proxy_user, proxy_pass = uri.userinfo.split(/:/) if uri.userinfo
Net::HTTP::Proxy(proxy_host, proxy_port,
proxy_user, proxy_pass).start('www.example.com') {|http|
# always connect to your.proxy.addr:8080 using specified username and password
:
}
Note that net/http never rely on HTTP_PROXY environment variable. If you want to use proxy, set it explicitly. Following Redirection
require 'net/http' require 'uri'
def fetch(uri_str, limit = 10)
# You should choose better exception.
raise ArgumentError, 'HTTP redirect too deep' if limit == 0
response = Net::HTTP.get_response(URI.parse(uri_str))
case response
when Net::HTTPSuccess then response
when Net::HTTPRedirection then fetch(response['location'], limit - 1)
else
response.error!
end
end
print fetch('http://www.ruby-lang.org')
Net::HTTPSuccess and Net::HTTPRedirection is a HTTPResponse class. All HTTPResponse objects belong to its own response class which indicate HTTP result status. For details of response classes, see section "HTTP Response Classes". Basic Authentication
require 'net/http'
Net::HTTP.start('www.example.com') {|http|
req = Net::HTTP::Get.new('/secret-page.html')
req.basic_auth 'account', 'password'
response = http.request(req)
print response.body
}
HTTP Request Classes
Here is HTTP request class hierarchy.
Net::HTTPRequest
Net::HTTP::Get
Net::HTTP::Head
Net::HTTP::Post
Net::HTTP::Put
Net::HTTP::Proppatch
Net::HTTP::Lock
Net::HTTP::Unlock
Net::HTTP::Options
Net::HTTP::Propfind
Net::HTTP::Delete
Net::HTTP::Move
Net::HTTP::Copy
Net::HTTP::Mkcol
Net::HTTP::Trace
HTTP Response Classes
Here is HTTP response class hierarchy. All classes are defined in Net module.
HTTPResponse
HTTPUnknownResponse
HTTPInformation # 1xx
HTTPContinue # 100
HTTPSwitchProtocl # 101
HTTPSuccess # 2xx
HTTPOK # 200
HTTPCreated # 201
HTTPAccepted # 202
HTTPNonAuthoritativeInformation # 203
HTTPNoContent # 204
HTTPResetContent # 205
HTTPPartialContent # 206
HTTPRedirection # 3xx
HTTPMultipleChoice # 300
HTTPMovedPermanently # 301
HTTPFound # 302
HTTPSeeOther # 303
HTTPNotModified # 304
HTTPUseProxy # 305
HTTPTemporaryRedirect # 307
HTTPClientError # 4xx
HTTPBadRequest # 400
HTTPUnauthorized # 401
HTTPPaymentRequired # 402
HTTPForbidden # 403
HTTPNotFound # 404
HTTPMethodNotAllowed # 405
HTTPNotAcceptable # 406
HTTPProxyAuthenticationRequired # 407
HTTPRequestTimeOut # 408
HTTPConflict # 409
HTTPGone # 410
HTTPLengthRequired # 411
HTTPPreconditionFailed # 412
HTTPRequestEntityTooLarge # 413
HTTPRequestURITooLong # 414
HTTPUnsupportedMediaType # 415
HTTPRequestedRangeNotSatisfiable # 416
HTTPExpectationFailed # 417
HTTPServerError # 5xx
HTTPInternalServerError # 500
HTTPNotImplemented # 501
HTTPBadGateway # 502
HTTPServiceUnavailable # 503
HTTPGatewayTimeOut # 504
HTTPVersionNotSupported # 505
Switching Net::HTTP versions
You can use net/http.rb 1.1 features (bundled with Ruby 1.6) by calling HTTP.version_1_1. Calling Net::HTTP.version_1_2 allows you to use 1.2 features again.
# example
Net::HTTP.start {|http1| ...(http1 has 1.2 features)... }
Net::HTTP.version_1_1
Net::HTTP.start {|http2| ...(http2 has 1.1 features)... }
Net::HTTP.version_1_2
Net::HTTP.start {|http3| ...(http3 has 1.2 features)... }
This function is NOT thread-safe.
