Class | RightAws::SqsGen2Interface |
In: |
lib/sqs/right_sqs_gen2_interface.rb
|
Parent: | RightAwsBase |
Right::Aws::SqsGen2Interface - RightScale‘s low-level Amazon SQS interface for API version 2008-01-01 and later. For explanations of the semantics of each call, please refer to Amazon‘s documentation at developer.amazonwebservices.com/connect/kbcategory.jspa?categoryID=31
This class provides a procedural interface to SQS. Conceptually it is mostly a pass-through interface to SQS and its API is very similar to the bare SQS API. For a somewhat higher-level and object-oriented interface, see RightAws::SqsGen2.
API_VERSION | = | "2008-01-01" |
DEFAULT_HOST | = | "queue.amazonaws.com" |
DEFAULT_PORT | = | 443 |
DEFAULT_PROTOCOL | = | 'https' |
REQUEST_TTL | = | 30 |
DEFAULT_VISIBILITY_TIMEOUT | = | 30 |
# File lib/sqs/right_sqs_gen2_interface.rb, line 53 53: def self.bench_sqs 54: @@bench.service 55: end
Creates a new SqsInterface instance. This instance is limited to operations on SQS objects created with Amazon‘s 2008-01-01 API version. This interface will not work on objects created with prior API versions. See Amazon‘s article "Migrating to Amazon SQS API version 2008-01-01" at: developer.amazonwebservices.com/connect/entry.jspa?externalID=1148
sqs = RightAws::SqsGen2Interface.new('1E3GDYEOGFJPIT75KDT40','hgTHt68JY07JKUY08ftHYtERkjgtfERn57DFE379', {:multi_thread => true, :logger => Logger.new('/tmp/x.log')})
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) :signature_version => '0' # The signature version : '0' or '1'(default) :logger => Logger Object} # Logger instance: logs to STDOUT if omitted }
# File lib/sqs/right_sqs_gen2_interface.rb, line 78 78: def initialize(aws_access_key_id=nil, aws_secret_access_key=nil, params={}) 79: init({ :name => 'SQS', 80: :default_host => ENV['SQS_URL'] ? URI.parse(ENV['SQS_URL']).host : DEFAULT_HOST, 81: :default_port => ENV['SQS_URL'] ? URI.parse(ENV['SQS_URL']).port : DEFAULT_PORT, 82: :default_protocol => ENV['SQS_URL'] ? URI.parse(ENV['SQS_URL']).scheme : DEFAULT_PROTOCOL }, 83: aws_access_key_id || ENV['AWS_ACCESS_KEY_ID'], 84: aws_secret_access_key || ENV['AWS_SECRET_ACCESS_KEY'], 85: params) 86: end
Returns short queue name by url.
RightSqs.queue_name_by_url('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue') #=> 'my_awesome_queue'
# File lib/sqs/right_sqs_gen2_interface.rb, line 301 301: def self.queue_name_by_url(queue_url) 302: queue_url[/[^\/]*$/] 303: rescue 304: on_exception 305: end
Removes all visible messages from queue. Return true or an exception.
sqs.clear_queue('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue') #=> true
# File lib/sqs/right_sqs_gen2_interface.rb, line 331 331: def clear_queue(queue_url) 332: while (pop_messages(queue_url, 10).length > 0) ; end # delete all messages in queue 333: true 334: rescue 335: on_exception 336: end
Creates a new queue, returning its URI.
sqs.create_queue('my_awesome_queue') #=> 'http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue'
# File lib/sqs/right_sqs_gen2_interface.rb, line 153 153: def create_queue(queue_name, default_visibility_timeout=nil) 154: req_hash = generate_request('CreateQueue', 'QueueName' => queue_name, 155: 'DefaultVisibilityTimeout' => default_visibility_timeout || DEFAULT_VISIBILITY_TIMEOUT ) 156: request_info(req_hash, SqsCreateQueueParser.new(:logger => @logger)) 157: rescue 158: on_exception 159: end
Deletes message from queue. Returns true or an exception. Amazon returns true on deletion of non-existent messages. You must use the receipt handle for a message to delete it, not the message ID.
From the SQS Developer Guide: "It is possible you will receive a message even after you have deleted it. This might happen on rare occasions if one of the servers storing a copy of the message is unavailable when you request to delete the message. The copy remains on the server and might be returned to you again on a subsequent receive request. You should create your system to be idempotent so that receiving a particular message more than once is not a problem. "
sqs.delete_message('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue', 'Euvo62/1nlIet...ao03hd9Sa0w==') #=> true
# File lib/sqs/right_sqs_gen2_interface.rb, line 276 276: def delete_message(queue_url, receipt_handle) 277: req_hash = generate_request('DeleteMessage', 'ReceiptHandle' => receipt_handle, :queue_url => queue_url) 278: request_info(req_hash, SqsStatusParser.new(:logger => @logger)) 279: rescue 280: on_exception 281: end
Deletes queue. Any messages in the queue are permanently lost. Returns true or an exception. Queue deletion can take up to 60 s to propagate through SQS. Thus, after a deletion, subsequent list_queues calls may still show the deleted queue. It is not unusual within the 60 s window to see the deleted queue absent from one list_queues call but present in the subsequent one. Deletion is eventual.
sqs.delete_queue('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue_2') #=> true
# File lib/sqs/right_sqs_gen2_interface.rb, line 185 185: def delete_queue(queue_url) 186: req_hash = generate_request('DeleteQueue', :queue_url => queue_url) 187: request_info(req_hash, SqsStatusParser.new(:logger => @logger)) 188: rescue 189: on_exception 190: end
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"}
# File lib/sqs/right_sqs_gen2_interface.rb, line 197 197: def get_queue_attributes(queue_url, attribute='All') 198: req_hash = generate_request('GetQueueAttributes', 'AttributeName' => attribute, :queue_url => queue_url) 199: request_info(req_hash, SqsGetQueueAttributesParser.new(:logger => @logger)) 200: rescue 201: on_exception 202: end
Returns approximate number of messages in queue.
sqs.get_queue_length('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue') #=> 3
# File lib/sqs/right_sqs_gen2_interface.rb, line 321 321: def get_queue_length(queue_url) 322: get_queue_attributes(queue_url)['ApproximateNumberOfMessages'].to_i 323: rescue 324: on_exception 325: end
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. Queue creation is an eventual operation and created queues may not show up in immediately subsequent list_queues calls.
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']
# File lib/sqs/right_sqs_gen2_interface.rb, line 169 169: def list_queues(queue_name_prefix=nil) 170: req_hash = generate_request('ListQueues', 'QueueNamePrefix' => queue_name_prefix) 171: request_info(req_hash, SqsListQueuesParser.new(:logger => @logger)) 172: rescue 173: on_exception 174: end
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"}
# File lib/sqs/right_sqs_gen2_interface.rb, line 359 359: def pop_message(queue_url) 360: messages = pop_messages(queue_url) 361: messages.blank? ? nil : messages[0] 362: rescue 363: on_exception 364: end
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) #=> [{"ReceiptHandle"=>"Euvo62/...+Zw==", "MD5OfBody"=>"16af2...81e3", "Body"=>"Goodbyte World!", "MessageId"=>"MEZI...JSWDE="}, {...}, ... , {...} ]
# File lib/sqs/right_sqs_gen2_interface.rb, line 344 344: def pop_messages(queue_url, number_of_messages=1) 345: messages = receive_message(queue_url, number_of_messages) 346: messages.each do |message| 347: delete_message(queue_url, message['ReceiptHandle']) 348: end 349: messages 350: rescue 351: on_exception 352: end
Returns short queue name by url.
sqs.queue_name_by_url('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue') #=> 'my_awesome_queue'
# File lib/sqs/right_sqs_gen2_interface.rb, line 311 311: def queue_name_by_url(queue_url) 312: self.class.queue_name_by_url(queue_url) 313: rescue 314: on_exception 315: end
Given the queue‘s short name, this call returns the queue URL or nil if queue is not found
sqs.queue_url_by_name('my_awesome_queue') #=> 'http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue'
# File lib/sqs/right_sqs_gen2_interface.rb, line 286 286: def queue_url_by_name(queue_name) 287: return queue_name if queue_name.include?('/') 288: queue_urls = list_queues(queue_name) 289: queue_urls.each do |queue_url| 290: return queue_url if queue_name_by_url(queue_url) == queue_name 291: end 292: nil 293: rescue 294: on_exception 295: end
Retrieves a list of messages from queue. Returns an array of hashes in format: {:id=>’message_id’, body=>’message_body’}
sqs.receive_message('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue',10, 5) #=> [{"ReceiptHandle"=>"Euvo62...kw==", "MD5OfBody"=>"16af2171b5b83cfa35ce254966ba81e3", "Body"=>"Goodbyte World!", "MessageId"=>"MUM4WlAyR...pYOTA="}, ..., {}]
Normally this call returns fewer messages than the maximum specified, even if they are available.
# File lib/sqs/right_sqs_gen2_interface.rb, line 233 233: def receive_message(queue_url, max_number_of_messages=1, visibility_timeout=nil) 234: return [] if max_number_of_messages == 0 235: req_hash = generate_post_request('ReceiveMessage', 'MaxNumberOfMessages' => max_number_of_messages, 'VisibilityTimeout' => visibility_timeout, 236: :queue_url => queue_url ) 237: request_info(req_hash, SqsReceiveMessageParser.new(:logger => @logger)) 238: rescue 239: on_exception 240: end
Sends a new message to a queue. Message size is limited to 8 KB. If successful, this call returns a hash containing key/value pairs for "MessageId" and "MD5OfMessageBody":
sqs.send_message('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue', 'message_1') #=> "1234567890...0987654321" => {"MessageId"=>"MEs4M0JKNlRCRTBBSENaMjROTk58QVFRNzNEREhDVFlFOVJDQ1JKNjF8UTdBRllCUlJUMjhKMUI1WDJSWDE=", "MD5OfMessageBody"=>"16af2171b5b83cfa35ce254966ba81e3"}
On failure, send_message raises an exception.
# File lib/sqs/right_sqs_gen2_interface.rb, line 252 252: def send_message(queue_url, message) 253: req_hash = generate_post_request('SendMessage', :message => message, :queue_url => queue_url) 254: request_info(req_hash, SqsSendMessagesParser.new(:logger => @logger)) 255: rescue 256: on_exception 257: end
Sets queue attribute. Returns true or an exception.
sqs.set_queue_attributes('http://queue.amazonaws.com/ZZ7XXXYYYBINS/my_awesome_queue', "VisibilityTimeout", 10) #=> true
From the SQS Dev Guide: "Currently, you can set only the VisibilityTimeout attribute for a queue… When you change a queue‘s attributes, the change can take up to 60 seconds to propagate throughout the SQS system."
NB: Attribute values may not be immediately available to other queries for some time after an update. See the SQS documentation for semantics, but in general propagation can take up to 60 s.
# File lib/sqs/right_sqs_gen2_interface.rb, line 217 217: def set_queue_attributes(queue_url, attribute, value) 218: req_hash = generate_request('SetQueueAttributes', 'Attribute.Name' => attribute, 'Attribute.Value' => value, :queue_url => queue_url) 219: request_info(req_hash, SqsStatusParser.new(:logger => @logger)) 220: rescue 221: on_exception 222: end