Class: Ropenstack::Rest

Inherits:
Object
  • Object
show all
Defined in:
lib/ropenstack/common/rest.rb

Overview

  • Name: Rest

* Description: A generic wrapper for basic rest functions with JSON data which return ruby hashes. * Author: Sam “Tehsmash” Betts * Date: 12/18/2012

Direct Known Subclasses

OpenstackService

Instance Method Summary collapse

Instance Method Details

#build_headers(token) ⇒ Object

Builds headers for requests which send JSON data, if a keystone token is supplied

it adds the X-Auth-Token field with the keystone token. Returns a hash which represents the http headers in a format accepted by Net::HTTP.



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# File 'lib/ropenstack/common/rest.rb', line 61

def build_headers(token)
  headers = {'Content-Type' =>'application/json'}
  unless token.nil? 
    headers['X-Auth-Token'] = token
  end
  return headers
end

#build_http(uri, timeout) ⇒ Object

Build a HTTP object having been given a timeout and a URI object Returns Net::HTTP object.



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# File 'lib/ropenstack/common/rest.rb', line 17

def build_http(uri, timeout)
  http = Net::HTTP.new(uri.host, uri.port)
  if(timeout > 0) 
          http.open_timeout = timeout
          http.read_timeout = timeout
  end
  return http
end

#delete_request(uri, token = nil, manage_errors = true) ⇒ Object

Wrapper function for delete requests, just provide a uri and it will return you a hash with the result data. For authenticated transactions a token can be provided. Implemented using the do_request method.



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# File 'lib/ropenstack/common/rest.rb', line 108

def delete_request(uri, token = nil, manage_errors = true)
  request = Net::HTTP::Delete.new(uri.request_uri, initheader = build_headers(token))
  return do_request(uri, request, manage_errors)
end

#do_request(uri, request, manage_errors = true, timeout = 10) ⇒ Object

The function which you call to perform a http request using the request object given in the parameters. By default manage errors is true, so all responses are passed through the error manager which converts the into Ropenstack errors.



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# File 'lib/ropenstack/common/rest.rb', line 75

def do_request(uri, request, manage_errors = true, timeout = 10)
  begin 
    http = build_http(uri, timeout)
    if(manage_errors)
      return error_manager(uri, http.request(request))
    else
      http.request(request)
      return { "Success" => true }
    end
  rescue Timeout::Error
    raise Ropenstack::TimeoutError, "It took longer than #{timeout} to connect to #{uri.to_s}"	
  rescue Errno::ECONNREFUSED
    raise Ropenstack::TimeoutError, "It took longer than #{timeout} to connect to #{uri.to_s}"	
  end	
end

#error_manager(uri, response) ⇒ Object

All responses from openstack where any errors need to be caught are passed through this function. Unless a successful response is passed it will throw a Ropenstack error. If successful returns a hash of response body, unless response body is nil then it returns an empty hash.



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# File 'lib/ropenstack/common/rest.rb', line 33

def error_manager(uri, response)
  case response
  when Net::HTTPSuccess then
    # This covers cases where the response may not validate as JSON.
    begin
      data = JSON.parse(response.body)
    rescue
      data = {}
    end
    ## Get the Headers out of the response object
    data['headers'] = response.to_hash()
    return data
  when Net::HTTPBadRequest
    raise Ropenstack::MalformedRequestError, response.body
  when Net::HTTPNotFound
    raise Ropenstack::NotFoundError, "URI: #{uri} \n" + response.body	
  when Net::HTTPUnauthorized
    raise Ropenstack::UnauthorisedError, response.body
  else
    raise Ropenstack::RopenstackError, response.body
  end
end

#get_request(uri, token = nil, manage_errors = true) ⇒ Object

Wrapper function for a get request, just provide a uri and it will return you a hash with the result data. For authenticated transactions a token can be provided. Implemented using the do_request method.



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# File 'lib/ropenstack/common/rest.rb', line 97

def get_request(uri, token = nil, manage_errors = true)
  request = Net::HTTP::Get.new(uri.request_uri, initheader = build_headers(token))
  return do_request(uri, request, manage_errors)
end

#post_request(uri, body, token = nil, manage_errors = true) ⇒ Object

Wrapper function for a put request, just provide a uri and a hash of the data to send, then it will return you a hash with the result data. For authenticated transactions a token can be provided.



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# File 'lib/ropenstack/common/rest.rb', line 132

def post_request(uri, body, token = nil, manage_errors = true)
  request = Net::HTTP::Post.new(uri.request_uri, initheader = build_headers(token))
  request.body = body.to_json
  return do_request(uri, request, manage_errors)    
end

#put_request(uri, body, token = nil, manage_errors = true) ⇒ Object

Wrapper function for a put request, just provide a uri and a hash of the data to send, then it will return you a hash with the result data. For authenticated transactions a token can be provided. Implemented using the do_request method



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# File 'lib/ropenstack/common/rest.rb', line 120

def put_request(uri, body, token = nil, manage_errors = true)
  request = Net::HTTP::Put.new(uri.request_uri, initheader = build_headers(token))
  request.body = body.to_json
  return do_request(uri, request, manage_errors)    
end