Module: RightAws::RightAwsBaseInterface

Included in:
AcfInterface, AcwInterface, AsInterface, Ec2, ElbInterface, RdsInterface, S3Interface, SdbInterface, SqsGen2Interface, SqsInterface
Defined in:
lib/awsbase/right_awsbase.rb

Constant Summary collapse

DEFAULT_SIGNATURE_VERSION = 
'2'
@@caching = 
false

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#aws_access_key_id ⇒ Object (readonly)

Current aws_access_key_id



191
192
193
 
# File 'lib/awsbase/right_awsbase.rb', line 191

def aws_access_key_id
  @aws_access_key_id
end

#cache ⇒ Object (readonly)

Cache



207
208
209
 
# File 'lib/awsbase/right_awsbase.rb', line 207

def cache
  @cache
end

#connection ⇒ Object (readonly)

RightHttpConnection instance



205
206
207
 
# File 'lib/awsbase/right_awsbase.rb', line 205

def connection
  @connection
end

#last_errors ⇒ Object

Last AWS errors list (used by AWSErrorHandler)



197
198
199
 
# File 'lib/awsbase/right_awsbase.rb', line 197

def last_errors
  @last_errors
end

#last_request ⇒ Object (readonly)

Last HTTP request object



193
194
195
 
# File 'lib/awsbase/right_awsbase.rb', line 193

def last_request
  @last_request
end

#last_request_id ⇒ Object

Returns Amazons request ID for the latest request



199
200
201
 
# File 'lib/awsbase/right_awsbase.rb', line 199

def last_request_id
  @last_request_id
end

#last_response ⇒ Object (readonly)

Last HTTP response object



195
196
197
 
# File 'lib/awsbase/right_awsbase.rb', line 195

def last_response
  @last_response
end

#logger ⇒ Object

Logger object



201
202
203
 
# File 'lib/awsbase/right_awsbase.rb', line 201

def logger
  @logger
end

#params ⇒ Object

Initial params hash



203
204
205
 
# File 'lib/awsbase/right_awsbase.rb', line 203

def params
  @params
end

#signature_version ⇒ Object (readonly)

Signature version (all services except s3)



209
210
211
 
# File 'lib/awsbase/right_awsbase.rb', line 209

def signature_version
  @signature_version
end

Class Method Details

.caching ⇒ Object 



183
184
185
 
# File 'lib/awsbase/right_awsbase.rb', line 183

def self.caching
  @@caching
end

.caching=(caching) ⇒ Object 



186
187
188
 
# File 'lib/awsbase/right_awsbase.rb', line 186

def self.caching=(caching)
  @@caching = caching
end

Instance Method Details

#amazonize_list(masks, list) ⇒ Object

Format array of items into Amazons handy hash (‘?’ is a place holder):

amazonize_list('Item', ['a', 'b', 'c']) =>
  { 'Item.1' => 'a', 'Item.2' => 'b', 'Item.3' => 'c' }

amazonize_list('Item.?.instance', ['a', 'c']) #=>
  { 'Item.1.instance' => 'a', 'Item.2.instance' => 'c' }

amazonize_list(['Item.?.Name', 'Item.?.Value'], {'A' => 'a', 'B' => 'b'}) #=>
  { 'Item.1.Name' => 'A', 'Item.1.Value' => 'a',
    'Item.2.Name' => 'B', 'Item.2.Value' => 'b'  }

amazonize_list(['Item.?.Name', 'Item.?.Value'], [['A','a'], ['B','b']]) #=>
  { 'Item.1.Name' => 'A', 'Item.1.Value' => 'a',
    'Item.2.Name' => 'B', 'Item.2.Value' => 'b'  }

amazonize_list(['Filter.?.Key', 'Filter.?.Value.?'], {'A' => ['aa','ab'], 'B' => ['ba','bb']}) #=>
amazonize_list(['Filter.?.Key', 'Filter.?.Value.?'], [['A',['aa','ab']], ['B',['ba','bb']]])   #=>
  {"Filter.1.Key"=>"A",
   "Filter.1.Value.1"=>"aa",
   "Filter.1.Value.2"=>"ab",
   "Filter.2.Key"=>"B",
   "Filter.2.Value.1"=>"ba",
   "Filter.2.Value.2"=>"bb"}



497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
 
# File 'lib/awsbase/right_awsbase.rb', line 497

def amazonize_list(masks, list) #:nodoc:
  groups = {}
  list.to_a.each_with_index do |list_item, i|
    masks.to_a.each_with_index do |mask, mask_idx|
      key = mask[/\?/] ? mask.dup : mask.dup + '.?'
      key.sub!('?', (i+1).to_s)
      value = list_item.to_a[mask_idx]
      if value.is_a?(Array)
        groups.merge!(amazonize_list(key, value))
      else
        groups[key] = value
      end
    end
  end
  groups
end

#cache_hits?(function, response, do_raise = :raise) ⇒ Boolean

Check if the aws function response hits the cache or not. If the cache hits:

  • raises an AwsNoChange exception if do_raise == :raise.

  • returnes parsed response from the cache if it exists or true otherwise.

If the cache miss or the caching is off then returns false.

Returns:

  • (Boolean) 


269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
 
# File 'lib/awsbase/right_awsbase.rb', line 269

def cache_hits?(function, response, do_raise=:raise)
  result = false
  if caching?
    function = function.to_sym
    # get rid of requestId (this bad boy was added for API 2008-08-08+ and it is uniq for every response)
    # feb 04, 2009 (load balancer uses 'RequestId' hence use 'i' modifier to hit it also)
    response = response.sub(%r{<requestId>.+?</requestId>}i, '')
    response_md5 = MD5.md5(response).to_s
    # check for changes
    unless @cache[function] && @cache[function][:response_md5] == response_md5
      # well, the response is new, reset cache data
      update_cache(function, {:response_md5 => response_md5, 
                              :timestamp    => Time.now, 
                              :hits         => 0, 
                              :parsed       => nil})
    else
      # aha, cache hits, update the data and throw an exception if needed
      @cache[function][:hits] += 1
      if do_raise == :raise
        raise(AwsNoChange, "Cache hit: #{function} response has not changed since "+
                           "#{@cache[function][:timestamp].strftime('%Y-%m-%d %H:%M:%S')}, "+
                           "hits: #{@cache[function][:hits]}.")
      else
        result = @cache[function][:parsed] || true
      end
    end
  end
  result
end

#caching? ⇒ Boolean

Returns true if the describe_xxx responses are being cached

Returns:

  • (Boolean) 


260
261
262
 
# File 'lib/awsbase/right_awsbase.rb', line 260

def caching?
  @params.key?(:cache) ? @params[:cache] : @@caching
end

#generate_request_impl(verb, action, options = {}) ⇒ Object

ACF, AMS, EC2, LBS and SDB uses this guy SQS and S3 use their own methods



315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
 
# File 'lib/awsbase/right_awsbase.rb', line 315

def generate_request_impl(verb, action, options={}) #:nodoc:
  # Form a valid http verb: 'GET' or 'POST' (all the other are not supported now)
  http_verb = verb.to_s.upcase
  # remove empty keys from request options
  options.delete_if { |key, value| value.nil? }
  # prepare service data
  service_hash = {"Action"         => action,
                  "AWSAccessKeyId" => @aws_access_key_id,
                  "Version"        => @params[:api_version] }
  service_hash.merge!(options)
  # Sign request options
  service_params = signed_service_params(@aws_secret_access_key, service_hash, http_verb, @params[:server], @params[:service])
  # Use POST if the length of the query string is too large
  # see http://docs.amazonwebservices.com/AmazonSimpleDB/2007-11-07/DeveloperGuide/MakingRESTRequests.html
  if http_verb != 'POST' && service_params.size > 2000
    http_verb = 'POST'
    if signature_version == '2'
      service_params = signed_service_params(@aws_secret_access_key, service_hash, http_verb, @params[:server], @params[:service])
    end
  end
  # create a request
  case http_verb
  when 'GET'
    request = Net::HTTP::Get.new("#{@params[:service]}?#{service_params}")
  when 'POST'
    request      = Net::HTTP::Post.new(@params[:service])
    request.body = service_params
    request['Content-Type'] = 'application/x-www-form-urlencoded; charset=utf-8'
  else
    raise "Unsupported HTTP verb #{verb.inspect}!"
  end
  # prepare output hash
  { :request  => request,
    :server   => @params[:server],
    :port     => @params[:port],
    :protocol => @params[:protocol] }
end

#get_connection(aws_service, request) ⇒ Object

:nodoc



353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
 
# File 'lib/awsbase/right_awsbase.rb', line 353

def get_connection(aws_service, request) #:nodoc
  server_url = "#{request[:protocol]}://#{request[:server]}:#{request[:port]}}"
  #
  case @params[:connections].to_s
  when 'dedicated'
    @connections_storage ||= {}
  else # 'dedicated'
    @connections_storage = (Thread.current[aws_service] ||= {})
  end
  #
  @connections_storage[server_url] ||= {}
  @connections_storage[server_url][:last_used_at] = Time.now
  @connections_storage[server_url][:connection] ||= Rightscale::HttpConnection.new(:exception => RightAws::AwsError, :logger => @logger)
  # keep X most recent connections (but were used not far than Y minutes ago)
  connections = 0
  @connections_storage.to_a.sort{|i1, i2| i2[1][:last_used_at] <=> i1[1][:last_used_at]}.to_a.each do |i|
    if i[0] != server_url && (@params[:max_connections] <= connections  || i[1][:last_used_at] < Time.now - @params[:connection_lifetime])
      # delete the connection from the list
      @connections_storage.delete(i[0])
      # then finish it
      i[1][:connection].finish((@params[:max_connections] <= connections) ? "out-of-limit" : "out-of-date") rescue nil
    else
      connections += 1
    end
  end
  @connections_storage[server_url][:connection]
end

#init(service_info, aws_access_key_id, aws_secret_access_key, params = {}) ⇒ Object

:nodoc:

Raises:



211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
 
# File 'lib/awsbase/right_awsbase.rb', line 211

def init(service_info, aws_access_key_id, aws_secret_access_key, params={}) #:nodoc:
  @params = params
  # If one defines EC2_URL he may forget to use a single slash as an "empty service" path.
  # Amazon does not like this therefore add this bad boy if he is missing...
  service_info[:default_service] = '/' if service_info[:default_service].blank?
  raise AwsError.new("AWS access keys are required to operate on #{service_info[:name]}") \
    if aws_access_key_id.blank? || aws_secret_access_key.blank?
  @aws_access_key_id     = aws_access_key_id
  @aws_secret_access_key = aws_secret_access_key
  # if the endpoint was explicitly defined - then use it
  if @params[:endpoint_url]
    @params[:server]   = URI.parse(@params[:endpoint_url]).host
    @params[:port]     = URI.parse(@params[:endpoint_url]).port
    @params[:service]  = URI.parse(@params[:endpoint_url]).path
    # make sure the 'service' path is not empty
    @params[:service]  = service_info[:default_service] if @params[:service].blank?
    @params[:protocol] = URI.parse(@params[:endpoint_url]).scheme
    @params[:region]   = nil
  else
    @params[:server]   ||= service_info[:default_host]
    @params[:server]     = "#{@params[:region]}.#{@params[:server]}" if @params[:region]
    @params[:port]     ||= service_info[:default_port]
    @params[:service]  ||= service_info[:default_service]
    @params[:protocol] ||= service_info[:default_protocol]
  end
#      @params[:multi_thread] ||= defined?(AWS_DAEMON)
  @params[:connections] ||= :shared # || :dedicated
  @params[:max_connections] ||= 10
  @params[:connection_lifetime] ||= 20*60
  @params[:api_version]  ||= service_info[:default_api_version]
  @logger = @params[:logger]
  @logger = RAILS_DEFAULT_LOGGER if !@logger && defined?(RAILS_DEFAULT_LOGGER)
  @logger = Logger.new(STDOUT)   if !@logger
  @logger.info "New #{self.class.name} using #{@params[:connections]} connections mode"
  @error_handler = nil
  @cache = {}
  @signature_version = (params[:signature_version] || DEFAULT_SIGNATURE_VERSION).to_s
end

#on_exception(options = {:raise=>true, :log=>true}) ⇒ Object

:nodoc:



303
304
305
306
 
# File 'lib/awsbase/right_awsbase.rb', line 303

def on_exception(options={:raise=>true, :log=>true}) # :nodoc:
  raise if $!.is_a?(AwsNoChange)
  AwsError::on_aws_exception(self, options)
end

#request_cache_or_info(method, link, parser_class, benchblock, use_cache = true) ⇒ Object

:nodoc:



452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
 
# File 'lib/awsbase/right_awsbase.rb', line 452

def request_cache_or_info(method, link, parser_class, benchblock, use_cache=true) #:nodoc:
  # We do not want to break the logic of parsing hence will use a dummy parser to process all the standard
  # steps (errors checking etc). The dummy parser does nothig - just returns back the params it received.
  # If the caching is enabled and hit then throw  AwsNoChange.
  # P.S. caching works for the whole images list only! (when the list param is blank)
  # check cache
  response, params = request_info(link, RightDummyParser.new)
  cache_hits?(method.to_sym, response.body) if use_cache
  parser = parser_class.new(:logger => @logger)
  benchblock.xml.add!{ parser.parse(response, params) }
  result = block_given? ? yield(parser) : parser.result
  # update parsed data
  update_cache(method.to_sym, :parsed => result) if use_cache
  result
end

#request_info_impl(aws_service, benchblock, request, parser, &block) ⇒ Object

All services uses this guy.



382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
 
# File 'lib/awsbase/right_awsbase.rb', line 382

def request_info_impl(aws_service, benchblock, request, parser, &block) #:nodoc:
  @connection    = get_connection(aws_service, request)
  @last_request  = request[:request]
  @last_response = nil
  response = nil
  blockexception = nil

  if(block != nil)
    # TRB 9/17/07 Careful - because we are passing in blocks, we get a situation where
    # an exception may get thrown in the block body (which is high-level
    # code either here or in the application) but gets caught in the
    # low-level code of HttpConnection.  The solution is not to let any
    # exception escape the block that we pass to HttpConnection::request.
    # Exceptions can originate from code directly in the block, or from user
    # code called in the other block which is passed to response.read_body.
    benchblock.service.add! do
      responsehdr = @connection.request(request) do |response|
      #########
        begin
          @last_response = response
          if response.is_a?(Net::HTTPSuccess)
            @error_handler = nil
            response.read_body(&block)
          else
            @error_handler = AWSErrorHandler.new(self, parser, :errors_list => self.class.amazon_problems) unless @error_handler
            check_result   = @error_handler.check(request)
            if check_result
              @error_handler = nil
              return check_result 
            end
            raise AwsError.new(@last_errors, @last_response.code, @last_request_id)
          end
        rescue Exception => e
          blockexception = e
        end
      end
      #########

      #OK, now we are out of the block passed to the lower level
      if(blockexception)
        raise blockexception
      end
      benchblock.xml.add! do
        parser.parse(responsehdr)
      end
      return parser.result
    end
  else
    benchblock.service.add!{ response = @connection.request(request) }
      # check response for errors...
    @last_response = response
    if response.is_a?(Net::HTTPSuccess)
      @error_handler = nil
      benchblock.xml.add! { parser.parse(response) }
      return parser.result
    else
      @error_handler = AWSErrorHandler.new(self, parser, :errors_list => self.class.amazon_problems) unless @error_handler
      check_result   = @error_handler.check(request)
      if check_result
        @error_handler = nil
        return check_result 
      end
      raise AwsError.new(@last_errors, @last_response.code, @last_request_id)
    end
  end
rescue
  @error_handler = nil
  raise
end

#signed_service_params(aws_secret_access_key, service_hash, http_verb = nil, host = nil, service = nil) ⇒ Object 



250
251
252
253
254
255
256
257
 
# File 'lib/awsbase/right_awsbase.rb', line 250

def signed_service_params(aws_secret_access_key, service_hash, http_verb=nil, host=nil, service=nil )
  case signature_version.to_s
  when '0' then AwsUtils::sign_request_v0(aws_secret_access_key, service_hash)
  when '1' then AwsUtils::sign_request_v1(aws_secret_access_key, service_hash)
  when '2' then AwsUtils::sign_request_v2(aws_secret_access_key, service_hash, http_verb, host, service)
  else raise AwsError.new("Unknown signature version (#{signature_version.to_s}) requested")
  end
end

#update_cache(function, hash) ⇒ Object 



299
300
301
 
# File 'lib/awsbase/right_awsbase.rb', line 299

def update_cache(function, hash)
  (@cache[function.to_sym] ||= {}).merge!(hash) if caching?
end