Class: RightAws::SqsInterface

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

Defined Under Namespace

Classes: SqsCreateQueueParser, SqsGetQueueAttributesParser, SqsGetVisibilityTimeoutParser, SqsListGrantsParser, SqsListQueuesParser, SqsReceiveMessagesParser, SqsSendMessagesParser, SqsStatusParser

Constant Summary collapse

SIGNATURE_VERSION = 
"1"
API_VERSION = 
"2007-05-01"
DEFAULT_HOST = 
"queue.amazonaws.com"
DEFAULT_PORT = 
443
DEFAULT_PROTOCOL = 
'https'
REQUEST_TTL = 
30
DEFAULT_VISIBILITY_TIMEOUT = 
30
@@amazon_problems =

A list of Amazon problems we can handle via AWSErrorHandler.

RightAws::AMAZON_PROBLEMS
@@bench_sqs = 
Benchmark::Tms.new()
@@bench_xml = 
Benchmark::Tms.new()

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(aws_access_key_id, aws_secret_access_key, params = {}) ⇒ SqsInterface

Creates a new SqsInterface instance.

sqs = RightAws::SqsInterface.new('1E3GDYEOGFJPIT75KDT40','hgTHt68JY07JKUY08ftHYtERkjgtfERn57DFE379', {:multi_thread => true, :logger => Logger.new('/tmp/x.log')}) #=> <RightSqs:0xb7af6264>

Params is a hash:

{:server       => 'queue.amazonaws.com' # Amazon service host: 'queue.amazonaws.com'(default)
 :port         => 443                   # Amazon service port: 80 or 443(default)
 :multi_thread => true|false            # Multi-threaded (connection per each thread): true or false(default)
 :logger       => Logger Object}        # Logger instance: logs to STDOUT if omitted }

Raises:



85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
 
# File 'lib/sqs/right_sqs_interface.rb', line 85

def initialize(aws_access_key_id, aws_secret_access_key, params={})
  @params = params
  raise AwsError.new("AWS access keys are required to operate on SQS") \
    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
    # params
  @params[:server]       ||= DEFAULT_HOST
  @params[:port]         ||= DEFAULT_PORT
  @params[:protocol]     ||= DEFAULT_PROTOCOL
  @params[:multi_thread] ||= defined?(AWS_DAEMON)
    # set logger
  @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[:multi_thread] ? 'multi' : 'single'}-threaded mode"
end

Instance Attribute Details

#aws_access_key_id ⇒ Object (readonly)

Current aws_access_key_id



39
40
41
 
# File 'lib/sqs/right_sqs_interface.rb', line 39

def aws_access_key_id
  @aws_access_key_id
end

#last_errors ⇒ Object

Last AWS errors list (used by AWSErrorHandler)



45
46
47
 
# File 'lib/sqs/right_sqs_interface.rb', line 45

def last_errors
  @last_errors
end

#last_request ⇒ Object (readonly)

Last HTTP request object



41
42
43
 
# File 'lib/sqs/right_sqs_interface.rb', line 41

def last_request
  @last_request
end

#last_request_id ⇒ Object

Last AWS request id (used by AWSErrorHandler)



47
48
49
 
# File 'lib/sqs/right_sqs_interface.rb', line 47

def last_request_id
  @last_request_id
end

#last_response ⇒ Object (readonly)

Last HTTP response object



43
44
45
 
# File 'lib/sqs/right_sqs_interface.rb', line 43

def last_response
  @last_response
end

#logger ⇒ Object

Logger object



49
50
51
 
# File 'lib/sqs/right_sqs_interface.rb', line 49

def logger
  @logger
end

#params ⇒ Object

Initial params hash



51
52
53
 
# File 'lib/sqs/right_sqs_interface.rb', line 51

def params
  @params
end

Class Method Details

.amazon_problems ⇒ Object

Returns a list of Amazon service responses which are known to be transient problems. We have to re-request if we get any of them, because the problem will probably disappear. By default this method returns the same value as the AMAZON_PROBLEMS const.



64
65
66
 
# File 'lib/sqs/right_sqs_interface.rb', line 64

def self.amazon_problems
  @@amazon_problems
end

.amazon_problems=(problems_list) ⇒ Object

Sets the list of Amazon side problems. Use in conjunction with the getter to append problems.



70
71
72
 
# File 'lib/sqs/right_sqs_interface.rb', line 70

def self.amazon_problems=(problems_list)
  @@amazon_problems = problems_list
end

.bench_sqs ⇒ Object

Benchmark::Tms instance for SQS access benchmarking.



57
 
# File 'lib/sqs/right_sqs_interface.rb', line 57

def self.bench_sqs; @@bench_sqs;  end

.bench_xml ⇒ Object

Benchmark::Tms instance for XML parsing benchmarking.



59
 
# File 'lib/sqs/right_sqs_interface.rb', line 59

def self.bench_xml; @@bench_xml; end

.queue_name_by_url(queue_url) ⇒ Object

Returns short queue name by url.

RightSqs.queue_name_by_url('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue') #=> 'my_awesome_queue'



446
447
448
449
450
 
# File 'lib/sqs/right_sqs_interface.rb', line 446

def self.queue_name_by_url(queue_url)
  queue_url[/[^\/]*$/]
rescue
  on_exception
end

Instance Method Details

#add_grant(queue_url, grantee_email_address, permission = nil) ⇒ Object

Adds grants for user (identified by email he registered at Amazon). Returns true or an exception. Permission = ‘FULLCONTROL’ | ‘RECEIVEMESSAGE’ | ‘SENDMESSAGE’.

sqs.add_grant('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue', '[email protected]', 'FULLCONTROL') #=> true



304
305
306
307
308
309
310
311
312
 
# File 'lib/sqs/right_sqs_interface.rb', line 304

def add_grant(queue_url, grantee_email_address, permission = nil)
  req_hash = generate_request('AddGrant', 
                              'Grantee.EmailAddress' => grantee_email_address,
                              'Permission'           => permission,
                              :queue_url             => queue_url)
  request_info(req_hash, SqsStatusParser.new(:logger => @logger))
rescue
  on_exception
end

#change_message_visibility(queue_url, message_id, visibility_timeout = 0) ⇒ Object

Changes message visibility timeout. Returns true or an exception.

sqs.change_message_visibility('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue', '1234567890...0987654321', 10) #=> true



417
418
419
420
421
422
423
424
425
 
# File 'lib/sqs/right_sqs_interface.rb', line 417

def change_message_visibility(queue_url, message_id, visibility_timeout=0)
  req_hash = generate_request('ChangeMessageVisibility', 
                              'MessageId'         => message_id,
                              'VisibilityTimeout' => visibility_timeout.to_s,
                              :queue_url          => queue_url)
  request_info(req_hash, SqsStatusParser.new(:logger => @logger))
rescue
  on_exception
end

#clear_queue(queue_url) ⇒ Object

Removes all visible messages from queue. Return true or an exception.

sqs.clear_queue('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue') #=> true



476
477
478
479
480
481
 
# File 'lib/sqs/right_sqs_interface.rb', line 476

def clear_queue(queue_url)
  while (m = pop_message(queue_url)) ; end   # delete all messages in queue
  true
rescue
  on_exception
end

#create_queue(queue_name, default_visibility_timeout = nil) ⇒ Object

Creates new queue. Returns new queue link.

sqs.create_queue('my_awesome_queue') #=> 'http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue'

PS Some queue based requests may not become available until a couple of minutes after queue creation (permission grant and removal for example)



209
210
211
212
213
214
 
# File 'lib/sqs/right_sqs_interface.rb', line 209

def create_queue(queue_name, default_visibility_timeout=nil)
  req_hash = generate_request('CreateQueue', 
                              'QueueName'                => queue_name,
                              'DefaultVisibilityTimeout' => default_visibility_timeout || DEFAULT_VISIBILITY_TIMEOUT )
  request_info(req_hash, SqsCreateQueueParser.new(:logger => @logger))
end

#delete_message(queue_url, message_id) ⇒ Object

Deletes message from queue. Returns true or an exception. Amazon returns true on deletion of non-existent messages.

sqs.delete_message('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue', '12345678904...0987654321') #=> true



404
405
406
407
408
409
410
411
 
# File 'lib/sqs/right_sqs_interface.rb', line 404

def delete_message(queue_url, message_id)
  req_hash = generate_request('DeleteMessage', 
                              'MessageId' => message_id,
                              :queue_url  => queue_url)
  request_info(req_hash, SqsStatusParser.new(:logger => @logger))
rescue
  on_exception
end

#delete_queue(queue_url, force_deletion = false) ⇒ Object

Deletes queue (queue must be empty or force_deletion must be set to true). Queue is identified by url. Returns true or an exception.

sqs.delete_queue('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue_2') #=> true



233
234
235
236
237
238
239
240
 
# File 'lib/sqs/right_sqs_interface.rb', line 233

def delete_queue(queue_url, force_deletion = false)
  req_hash = generate_request('DeleteQueue', 
                              'ForceDeletion' => force_deletion.to_s,
                              :queue_url      => queue_url)
  request_info(req_hash, SqsStatusParser.new(:logger => @logger))
rescue
  on_exception
end

#force_clear_queue(queue_url) ⇒ Object

Deletes queue then re-creates it (restores attributes also). The fastest method to clear big queue or queue with invisible messages. Return true or an exception.

sqs.force_clear_queue('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue') #=> true

PS This function is no longer supported. Amazon has changed the SQS semantics to require at least 60 seconds between queue deletion and creation. Hence this method will fail with an exception.



490
491
492
493
494
495
496
497
498
499
500
501
502
 
# File 'lib/sqs/right_sqs_interface.rb', line 490

def force_clear_queue(queue_url)
  queue_name       = queue_name_by_url(queue_url)
  queue_attributes = get_queue_attributes(queue_url)
  force_delete_queue(queue_url)
  create_queue(queue_name)
    # hmmm... The next line is a trick. Amazon do not want change attributes immediately after queue creation
    # So we do 'empty' get_queue_attributes. Probably they need some time to allow attributes change.
  get_queue_attributes(queue_url)  
  queue_attributes.each{ |attribute, value| set_queue_attributes(queue_url, attribute, value) }
  true
rescue
  on_exception
end

#force_delete_queue(queue_url) ⇒ Object

Deletes queue even if it has messages. Return true or an exception.

force_delete_queue('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue') #=> true

P.S. same as delete_queue('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue', true)



509
510
511
512
513
 
# File 'lib/sqs/right_sqs_interface.rb', line 509

def force_delete_queue(queue_url)
  delete_queue(queue_url, true)
rescue
  on_exception
end

#generate_request(action, param = {}) ⇒ Object

Generates a request hash for the query API



117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
 
# File 'lib/sqs/right_sqs_interface.rb', line 117

def generate_request(action, param={})  # :nodoc:
    # Sometimes we need to use queue uri (delete queue etc)
    # In that case we will use Symbol key: 'param[:queue_url]'
  queue_uri = param[:queue_url] ? URI(param[:queue_url]).path : '/'
    # remove unset(=optional) and symbolyc keys
  param.each{ |key, value| param.delete(key) if (value.nil? || key.is_a?(Symbol)) }
    # prepare output hash
  request_hash = { "Action"           => action,
                   # "Expires"          => Time.now.utc.since(REQUEST_TTL).strftime("%Y-%m-%dT%H:%M:%SZ"),
                   "Expires"          => (Time.now + REQUEST_TTL).utc.strftime("%Y-%m-%dT%H:%M:%SZ"),
                   "AWSAccessKeyId"   => @aws_access_key_id,
                   "Version"          => API_VERSION,
                   "SignatureVersion" => SIGNATURE_VERSION }
  request_hash.update(param)
  request_data   = request_hash.sort{|a,b| (a[0].to_s.downcase)<=>(b[0].to_s.downcase)}.to_s
  request_hash['Signature'] = Base64.encode64( OpenSSL::HMAC.digest( OpenSSL::Digest::Digest.new( "sha1" ), @aws_secret_access_key, request_data)).strip
  request_params = request_hash.to_a.collect{|key,val| key.to_s + "=" + CGI::escape(val.to_s) }.join("&")
  request        = Net::HTTP::Get.new("#{queue_uri}?#{request_params}")
    # prepare output hash
  { :request  => request, 
    :server   => @params[:server],
    :port     => @params[:port],
    :protocol => @params[:protocol] }
end

#generate_rest_request(method, param) ⇒ Object

Generates a request hash for the REST API



143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
 
# File 'lib/sqs/right_sqs_interface.rb', line 143

def generate_rest_request(method, param) # :nodoc:
  queue_uri = param[:queue_url] ? URI(param[:queue_url]).path : '/'
  message   = param[:message]                # extract message body if nesessary
    # remove unset(=optional) and symbolyc keys
  param.each{ |key, value| param.delete(key) if (value.nil? || key.is_a?(Symbol)) }
    # created request
  param_to_str = param.to_a.collect{|key,val| key.to_s + "=" + CGI::escape(val.to_s) }.join("&")
  param_to_str = "?#{param_to_str}" unless param_to_str.blank?
  request = "Net::HTTP::#{method.capitalize}".constantize.new("#{queue_uri}#{param_to_str}")
  request.body = message if message
    # set main headers
  request['content-md5']  = ''
  request['Content-Type'] = 'text/plain'
  request['Date']         = Time.now.httpdate
    # generate authorization string
  auth_string = "#{method.upcase}\n#{request['content-md5']}\n#{request['Content-Type']}\n#{request['Date']}\n#{CGI::unescape(queue_uri)}"
  signature   = Base64.encode64(OpenSSL::HMAC.digest(OpenSSL::Digest::Digest.new("sha1"), @aws_secret_access_key, auth_string)).strip
    # set other headers
  request['Authorization'] = "AWS #{@aws_access_key_id}:#{signature}"
  request['AWS-Version']   = API_VERSION
    # prepare output hash
  { :request  => request, 
    :server   => @params[:server],
    :port     => @params[:port],
    :protocol => @params[:protocol] }
end

#get_queue_attributes(queue_url, attribute = 'All') ⇒ Object

Retrieves the queue attribute(s). Returns a hash of attribute(s) or an exception.

sqs.get_queue_attributes('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue') #=> {"ApproximateNumberOfMessages"=>"0", "VisibilityTimeout"=>"30"}



246
247
248
249
250
251
252
253
 
# File 'lib/sqs/right_sqs_interface.rb', line 246

def get_queue_attributes(queue_url, attribute='All')
  req_hash = generate_request('GetQueueAttributes', 
                              'Attribute' => attribute,
                              :queue_url  => queue_url)
  request_info(req_hash, SqsGetQueueAttributesParser.new(:logger => @logger))
rescue
  on_exception
end

#get_queue_length(queue_url) ⇒ Object

Returns approximate number of messages in queue.

sqs.get_queue_length('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue') #=> 3



466
467
468
469
470
 
# File 'lib/sqs/right_sqs_interface.rb', line 466

def get_queue_length(queue_url)
  get_queue_attributes(queue_url)['ApproximateNumberOfMessages'].to_i
rescue
  on_exception
end

#get_visibility_timeout(queue_url) ⇒ Object

Retrieves visibility timeout.

sqs.get_visibility_timeout('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue') #=> 15

See also: get_queue_attributes



293
294
295
296
297
298
 
# File 'lib/sqs/right_sqs_interface.rb', line 293

def get_visibility_timeout(queue_url)
  req_hash = generate_request('GetVisibilityTimeout', :queue_url => queue_url )
  request_info(req_hash, SqsGetVisibilityTimeoutParser.new(:logger => @logger))
rescue
  on_exception
end

#list_grants(queue_url, grantee_email_address = nil, permission = nil) ⇒ Object

Retrieves hash of grantee_id => perms for this queue:

sqs.list_grants('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue') #=>
  {"000000000000000000000001111111111117476c7fea6efb2c3347ac3ab2792a"=>{:name=>"root", :perms=>["FULLCONTROL"]},
   "00000000000000000000000111111111111e5828344600fc9e4a784a09e97041"=>{:name=>"myawesomefriend", :perms=>["FULLCONTROL"]}



320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
 
# File 'lib/sqs/right_sqs_interface.rb', line 320

def list_grants(queue_url, grantee_email_address=nil, permission = nil)
  req_hash = generate_request('ListGrants', 
                              'Grantee.EmailAddress' => grantee_email_address,
                              'Permission'           => permission,
                              :queue_url             => queue_url)
  response = request_info(req_hash, SqsListGrantsParser.new(:logger => @logger))
    # One user may have up to 3 permission records for every queue.
    # We will join these records to one.
  result = {}    
  response.each do |perm|
    id = perm[:id]
      # create hash for new user if unexisit
    result[id] = {:perms=>[]} unless result[id]
      # fill current grantee params
    result[id][:perms] << perm[:permission]
    result[id][:name] = perm[:name]
  end
  result
end

#list_queues(queue_name_prefix = nil) ⇒ Object

Lists all queues owned by this user that have names beginning with queue_name_prefix. If queue_name_prefix is omitted then retrieves a list of all queues.

sqs.create_queue('my_awesome_queue')
sqs.create_queue('my_awesome_queue_2')
sqs.list_queues('my_awesome') #=> ['http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue','http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue_2']



222
223
224
225
226
227
 
# File 'lib/sqs/right_sqs_interface.rb', line 222

def list_queues(queue_name_prefix=nil)
  req_hash = generate_request('ListQueues', 'QueueNamePrefix' => queue_name_prefix)
  request_info(req_hash, SqsListQueuesParser.new(:logger => @logger))
rescue
  on_exception
end

#multi_thread ⇒ Object

Return true if this RightS3 instance is running in multi_thread state and false otherwise.



108
109
110
 
# File 'lib/sqs/right_sqs_interface.rb', line 108

def multi_thread
  @params[:multi_thread]
end

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

:nodoc:



103
104
105
 
# File 'lib/sqs/right_sqs_interface.rb', line 103

def on_exception(options={:raise=>true, :log=>true}) # :nodoc:
  AwsError::on_aws_exception(self, options)
end

#peek_message(queue_url, message_id) ⇒ Object

Peeks message from queue by message id. Returns message in format of {:id=>'message_id', :body=>'message_body'} or nil.

sqs.peek_message('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue', '1234567890...0987654321') #=>
  {:id=>"12345678904GEZX9746N|0N9ED344VK5Z3SV1DTM0|1RVYH4X3TJ0987654321", :body=>"message_1"}



378
379
380
381
382
383
384
 
# File 'lib/sqs/right_sqs_interface.rb', line 378

def peek_message(queue_url, message_id)
  req_hash = generate_rest_request('GET', :queue_url => "#{queue_url}/#{CGI::escape message_id}" )
  messages = request_info(req_hash, SqsReceiveMessagesParser.new(:logger => @logger))
  messages.blank? ? nil : messages[0]
rescue
  on_exception
end

#pop_message(queue_url) ⇒ Object

Pops (retrieves and deletes) first accessible message from queue. Returns the message in format {:id=>'message_id', :body=>'message_body'} or nil.

sqs.pop_message('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue') #=>
  {:id=>"12345678904GEZX9746N|0N9ED344VK5Z3SV1DTM0|1RVYH4X3TJ0987654321", :body=>"message_1"}



550
551
552
553
554
555
 
# File 'lib/sqs/right_sqs_interface.rb', line 550

def pop_message(queue_url)
  messages = pop_messages(queue_url)
  messages.blank? ? nil : messages[0]
rescue
  on_exception
end

#pop_messages(queue_url, number_of_messages = 1) ⇒ Object

Pops (retrieves and deletes) up to ‘number_of_messages’ from queue. Returns an array of retrieved messages in format: [{:id=>'message_id', :body=>'message_body'}].

sqs.pop_messages('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue', 3) #=>
 [{:id=>"12345678904GEZX9746N|0N9ED344VK5Z3SV1DTM0|1RVYH4X3TJ0987654321", :body=>"message_1"}, ..., {}]



535
536
537
538
539
540
541
542
543
 
# File 'lib/sqs/right_sqs_interface.rb', line 535

def pop_messages(queue_url, number_of_messages=1)
  messages = receive_messages(queue_url, number_of_messages)
  messages.each do |message|
    delete_message(queue_url, message[:id])
  end
  messages
rescue
  on_exception
end

#queue_name_by_url(queue_url) ⇒ Object

Returns short queue name by url.

sqs.queue_name_by_url('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue') #=> 'my_awesome_queue'



456
457
458
459
460
 
# File 'lib/sqs/right_sqs_interface.rb', line 456

def queue_name_by_url(queue_url)
  self.class.queue_name_by_url(queue_url)
rescue
  on_exception
end

#queue_url_by_name(queue_name) ⇒ Object

Returns queue url by queue short name or nil if queue is not found

sqs.queue_url_by_name('my_awesome_queue') #=> 'http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue'



431
432
433
434
435
436
437
438
439
440
 
# File 'lib/sqs/right_sqs_interface.rb', line 431

def queue_url_by_name(queue_name)
  return queue_name if queue_name.include?('/')
  queue_urls = list_queues(queue_name)
  queue_urls.each do |queue_url|
    return queue_url if queue_name_by_url(queue_url) == queue_name
  end
  nil
rescue
  on_exception
end

#receive_message(queue_url, visibility_timeout = nil) ⇒ Object

Reads first accessible message from queue. Returns message as a hash: {:id=>'message_id', :body=>'message_body'} or nil.

sqs.receive_message('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue', 10) #=>
  {:id=>"12345678904GEZX9746N|0N9ED344VK5Z3SV1DTM0|1RVYH4X3TJ0987654321", :body=>"message_1"}



520
521
522
523
524
525
 
# File 'lib/sqs/right_sqs_interface.rb', line 520

def receive_message(queue_url, visibility_timeout=nil)
  result = receive_messages(queue_url, 1, visibility_timeout)
  result.blank? ? nil : result[0]
rescue
  on_exception
end

#receive_messages(queue_url, number_of_messages = 1, visibility_timeout = nil) ⇒ Object

Retrieves a list of messages from queue. Returns an array of hashes in format: {:id=>'message_id', body=>'message_body'}

sqs.receive_messages('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue',10, 5) #=>
 [{:id=>"12345678904GEZX9746N|0N9ED344VK5Z3SV1DTM0|1RVYH4X3TJ0987654321", :body=>"message_1"}, ..., {}]

P.S. Usually returns fewer messages than requested even if they are available.



362
363
364
365
366
367
368
369
370
371
 
# File 'lib/sqs/right_sqs_interface.rb', line 362

def receive_messages(queue_url, number_of_messages=1, visibility_timeout=nil)
  return [] if number_of_messages == 0
  req_hash = generate_rest_request('GET',
                                   'NumberOfMessages'  => number_of_messages,
                                   'VisibilityTimeout' => visibility_timeout,
                                   :queue_url          => "#{queue_url}/front" )
  request_info(req_hash, SqsReceiveMessagesParser.new(:logger => @logger))
rescue
  on_exception
end

#remove_grant(queue_url, grantee_email_address_or_id, permission = nil) ⇒ Object

Revokes permission from user. Returns true or an exception.

sqs.remove_grant('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue', '[email protected]', 'FULLCONTROL') #=> true



344
345
346
347
348
349
350
351
352
353
 
# File 'lib/sqs/right_sqs_interface.rb', line 344

def remove_grant(queue_url, grantee_email_address_or_id, permission = nil)
  grantee_key = grantee_email_address_or_id.include?('@') ? 'Grantee.EmailAddress' : 'Grantee.ID'
  req_hash = generate_request('RemoveGrant', 
                              grantee_key  => grantee_email_address_or_id,
                              'Permission' => permission,
                              :queue_url   => queue_url)
  request_info(req_hash, SqsStatusParser.new(:logger => @logger))
rescue
  on_exception
end

#request_info(request, parser) ⇒ Object

Sends request to Amazon and parses the response Raises AwsError if any banana happened



173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
 
# File 'lib/sqs/right_sqs_interface.rb', line 173

def request_info(request, parser) # :nodoc:
  thread = @params[:multi_thread] ? Thread.current : Thread.main
  thread[:sqs_connection] ||= Rightscale::HttpConnection.new(:exception => AwsError)
  @last_request  = request[:request]
  @last_response = nil
  response=nil
  
  @@bench_sqs.add!{ response = thread[:sqs_connection].request(request) }
    # check response for errors...
  @last_response = response
  if response.is_a?(Net::HTTPSuccess)
    @error_handler = nil
    @@bench_xml.add! { parser.parse(response) }
    return parser.result
  else
    @error_handler = AWSErrorHandler.new(self, parser, @@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
  @error_handler = nil
  raise
end

#send_message(queue_url, message) ⇒ Object Also known as: push_message

Sends new message to queue.Returns ‘message_id’ or raises an exception.

sqs.send_message('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue', 'message_1') #=> "1234567890...0987654321"



390
391
392
393
394
395
396
397
 
# File 'lib/sqs/right_sqs_interface.rb', line 390

def send_message(queue_url, message)
  req_hash = generate_rest_request('PUT',
                                   :message   => message,
                                   :queue_url => "#{queue_url}/back")
  request_info(req_hash, SqsSendMessagesParser.new(:logger => @logger))
rescue
  on_exception
end

#set_queue_attributes(queue_url, attribute, value) ⇒ Object

Sets queue attribute. Returns true or an exception.

sqs.set_queue_attributes('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue', "VisibilityTimeout", 10) #=> true

P.S. Amazon returns success even if the attribute does not exist. Also, attribute values may not be immediately available to other queries for some time after an update (see the SQS documentation for semantics).



262
263
264
265
266
267
268
269
270
 
# File 'lib/sqs/right_sqs_interface.rb', line 262

def set_queue_attributes(queue_url, attribute, value)
  req_hash = generate_request('SetQueueAttributes', 
                              'Attribute' => attribute,
                              'Value'     => value,
                              :queue_url  => queue_url)
  request_info(req_hash, SqsStatusParser.new(:logger => @logger))
rescue
  on_exception
end

#set_visibility_timeout(queue_url, visibility_timeout = nil) ⇒ Object

Sets visibility timeout. Returns true or an exception.

sqs.set_visibility_timeout('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue', 15) #=> true

See also: set_queue_attributes



278
279
280
281
282
283
284
285
 
# File 'lib/sqs/right_sqs_interface.rb', line 278

def set_visibility_timeout(queue_url, visibility_timeout=nil)
  req_hash = generate_request('SetVisibilityTimeout', 
                              'VisibilityTimeout' => visibility_timeout || DEFAULT_VISIBILITY_TIMEOUT,
                              :queue_url => queue_url )
  request_info(req_hash, SqsStatusParser.new(:logger => @logger))
rescue
  on_exception
end