Class: Restr

Inherits:
Object
  • Object
show all
Defined in:
lib/restr.rb

Overview

A very simple REST client, best explained by example:

# Retrieve a Kitten and print its name and colour
kitten = Restr.get('http://example.com/kittens/1.xml')
puts kitten['name']
puts kitten['colour']

# Create a Kitten
kitten = Restr.post('http://example.com/kittens.xml', 
  :name => 'batman', :colour => 'black')

# Update a Kitten
kitten = Restr.put('http://example.com/kittens/1.xml', 
  :age => '6 months')

# Delete a Kitten :(
kitten = Restr.delete('http://example.com/kittens/1.xml')

# Retrieve a list of Kittens
kittens = Restr.get('http://example.com/kittens.xml')

When the response to a Restr request has content type ‘text/xml’, the response body will be parsed from XML into a nested Hash (using XmlSimple – see xml-simple.rubyforge.org/). Otherwise the response is

returned untouched, as a String.

Authentication

If the remote REST resource requires authentication (Restr only supports HTTP Basic authentication, for now):

Restr.get('http://example.com/kittens/1.xml, {}, 
  {:username => 'foo', :password => 'bar'})

Logging

A standard Ruby Logger can be attached to the Restr client like so:

logger = Logger.new('restr.log')
logger.level = Logger::DEBUG
Restr.logger = logger

Restr will now log its activity to the given Logger. The default_logger can be overridden by supplying a :logger option to a client call:

kitten_logger = Logger.new('kitten.log'}
Restr.get('http://example.com/kittens/1.xml, {}, 
  {:logger => kitten_logger)

Defined Under Namespace

Modules: VERSION Classes: InvalidRequestMethod

Constant Summary collapse

@@logger = 
nil
@@request_timeout = 
180

Class Method Summary collapse

Class Method Details

.do(method, url, params = {}, options = {}) ⇒ Object 



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# File 'lib/restr.rb', line 102

def self.do(method, url, params = {}, options = {})
  #puts "METHOD:  #{method.inspect}"
  #puts "URL:     #{url.inspect}"
  #puts "PARAMS:  #{params.inspect}"
  #puts "OPTIONS: #{options.inspect}"
  
  uri = URI.parse(url)
  
  params = {} unless params
  options = {} unless options
  
  logger = options[:logger] || self.logger
    
  method_mod = method.to_s.downcase.capitalize
  unless Net::HTTP.const_defined?(method_mod)
    raise InvalidRequestMethod, 
      "Callback method #{method.inspect} is not a valid HTTP request method."
  end
  
  if method_mod == 'Get'
    q = params.collect{|k,v| "#{CGI.escape(k.to_s)}=#{CGI.escape(v.to_s)}"}.join("&")
    if uri.query
      uri.query += "&#{q}"
    else
      uri.query = q
    end
  end
  
  req = Net::HTTP.const_get(method_mod).new(uri.request_uri)
  
  
  if options[:username] || options['username']
    req.basic_auth options[:username] || options['username'], options[:password] || options['password']
  end
  
  if params.kind_of?(Hash) && method_mod != 'Get' && method_mod != 'get'
    req.set_form_data(params, '&')
  end
  
  logger.debug("Sending #{method.inspect} request to #{url.inspect} "+
      (method.to_s == 'get' ? "params" : "data")+" #{params.inspect}"+
      (options.blank? ? "" : " with options #{options.inspect}}")+".") if logger
 
  client = Net::HTTP.new(uri.host, uri.port)
  client.use_ssl = (uri.scheme == 'https')
  
  timeout = Restr.request_timeout
  client.read_timeout = timeout
  
  begin
    res = client.start do |http|
      http.request(req)
    end
  rescue Timeout::Error
    res = TimeoutError, "Request timed out after #{timeout} seconds."
  end
  
  case res
  when Net::HTTPSuccess
    if res.content_type =~ /[\/+]xml$/
      logger.debug("Got XML response: \n#{res.body}") if logger
      return XmlSimple.xml_in(res.body,
        'forcearray'   => false,
        'keeproot'     => false
      )
    else
      logger.debug("Got #{res.content_type.inspect} response: \n#{res.body}") if logger
      return res.body
    end
  when TimeoutError
    logger.debug(res) if logger
    return XmlSimple.xml_in(res,
        'forcearray'   => false,
        'keeproot'     => false
      )
  else
    $LAST_ERROR_BODY = res.body # FIXME: this is dumb... need a better way of reporting errors
    $LAST_ERROR_RESPONSE = res # this is currently unused within Restr, but may be useful for debugging 
    logger.error("Got error response '#{res.message}(#{res.code})': #{res.body.blank? ? '(blank response body)' : res.body}") if logger
    res.error!
  end
end

.logger ⇒ Object 



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# File 'lib/restr.rb', line 94

def self.logger
  @@logger
end

.logger=(logger) ⇒ Object 



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# File 'lib/restr.rb', line 88

def self.logger=(logger)
  @@logger = logger.dup
  # ActiveSupport's BufferedLogger doesn't seem to support progname= :(
  @@logger.progname = self.name if @@logger.respond_to?(:progname)
end

.method_missing(method, *args) ⇒ Object 



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# File 'lib/restr.rb', line 98

def self.method_missing(method, *args)
  self.do(method, args[0], args[1] || {}, args[2])
end