Class: Rubizon::Request

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

Overview

Represents a request to be made to AWS.

Starts with access credentials and specifications for the product, such as its ARN, elements of its URL and query elements.

To this is added specifications for the specific action to be performed.

Request builds a URL for the action and signs the request. It then makes the entire URL and various components of it available for whatever transport mechanism is to be used.

A new instance of Request is to be created for each request sent to AWS

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(credentials, scheme, host, path, query_elements = {}) ⇒ Request

Initialize the request.

credentials - A Rubizon::SecurityCredentials object that 

encapsulates an AWS key pair.
It will be used to sign the request.

scheme - The scheme to be used: ‘http’ or ‘https’ host - The name of the HTTP host to serve this request path - The URL path, typically ‘/’. query_elements - A hash of key/value pairs to be included in the 

  query string.  
_omit - If an element with a key of '_omit' is included,
        the value must be an array containing names of keys
        to be omitted from the query_elements array before
        the request is signed and the query string formed.
        This allows allowing SignatureMethod or 
        SignatureVersion to be specified, even if they are
        not to be included in the query string.
SignatureVersion - The signature version to be used, such
        as 1 or 2.  This should be a numeric value.  If not
        present, signature version 1 is implied.
SignatureMethod - The signature methods defined for version
        two are HmacSHA256 and HmacSHA1.



37
38
39
40
41
42
43
 
# File 'lib/rubizon/request.rb', line 37

def initialize(credentials,scheme,host,path,query_elements={})
  @credentials= credentials
  @scheme= scheme
  @host= host
  @path= path
  @query_elements= query_elements.dup
end

Instance Attribute Details

#canonical_querystring ⇒ Object (readonly)

An artifact of the signature version 2 signing process: The query string portion of the string to sign.

This is of possible debugging value.



111
112
113
 
# File 'lib/rubizon/request.rb', line 111

def canonical_querystring
  @canonical_querystring
end

#host ⇒ Object (readonly)

Returns the host (domain and subdomains) of the product served by this object.



73
74
75
 
# File 'lib/rubizon/request.rb', line 73

def host
  @host
end

#path ⇒ Object

Returns the path part of the URL of the product served by this object, typically ‘/’.



77
78
79
 
# File 'lib/rubizon/request.rb', line 77

def path
  @path
end

#scheme ⇒ Object (readonly)

Returns the URL scheme, such as http or https



69
70
71
 
# File 'lib/rubizon/request.rb', line 69

def scheme
  @scheme
end

#string_to_sign ⇒ Object (readonly)

An artifact of the signature version 2 signing process: The string that is used to calculate the signature.

This is of possible debugging value.



116
117
118
 
# File 'lib/rubizon/request.rb', line 116

def string_to_sign
  @string_to_sign
end

Instance Method Details

#add_query_elements(query_elements) ⇒ Object

Add key/value pairs to the query_elements. Typically, these additional elements will be added to specify the action to be taken or subject of that action and parameters of that action or subject.

query_elements - A Hash containing key/value pairs to be added to the

query string.

returns self



63
64
65
66
 
# File 'lib/rubizon/request.rb', line 63

def add_query_elements(query_elements)
  @query_elements.merge! query_elements
  self
end

#append_to_path(path) ⇒ Object

Append additional elements to the currently defined path.



46
47
48
 
# File 'lib/rubizon/request.rb', line 46

def append_to_path(path)
  @path+= path
end

#endpoint ⇒ Object

Returns the product’s endpoint. The endpoint is that part of a URL that includes the scheme, host, and path, but not the query string. An action may extend the product’s path, but otherwise would retain the rest of the endpoint.



83
84
85
 
# File 'lib/rubizon/request.rb', line 83

def endpoint
  @endpoint||= "#{@scheme}://#{@host}#{@path}"
end

#query_string ⇒ Object

Create a query string from a hash and sign it. The signature algorithm will be determined from the query elements, such as SignatureVersion

The query string, once created, is immutable.



92
93
94
95
96
97
98
99
 
# File 'lib/rubizon/request.rb', line 92

def query_string
  return @query_string ||=
    if @query_elements['SignatureVersion'].to_i == 2
      query_string_sig2
    else
      raise UnsupportedSignatureVersionError, 'Only signature version 2 requests are supported at this time'
    end
end

#url ⇒ Object

Returns the full URL

The query string portion of the URL, once created, is immutable.



104
105
106
 
# File 'lib/rubizon/request.rb', line 104

def url
  endpoint+'?'+query_string
end