Introducing Amazon SQS

Meet Lee @leesto • PHPSW Organiser • Web Team Lead for Gradwell • Theatre Tech • Theme Park Fan • Occasional Photographer

What is SQS – Amazon Web Services “Amazon SQS is a distributed queue system that enables web service applications to quickly and reliably queue messages that one component in the application generates to be consumed by another component. A queue is a temporary repository for messages that are awaiting processing.”

Why Queues? Ideal for tasks we don’t need to complete in real time Don’t keep the user waiting Help handle incoming data / content Help scale large tasks

Why SQS? Amazon runs the service for you High availability Free for the first 1,000,000 requests per month $0.50 per 1 million after AWS SDK

Queues Hold the messages to be processed Uniquely named per account Ability to build in a processing delay (up to 15 minutes) Can be created / configured through the UI or API

Messages Contains the actual job you want processed 1 blob - up to 256 KB Found it useful to have this as a JSON object Option for storing additional attributes

Create a Message Need to know the URL - separate call to get the URL from a name $this -> awsClient -> sendMessage ( array (  

'QueueUrl' => 'http://sqs.us-east-1.amazonaws.com/123456789012/ myQueue' ,  

'MessageBody' => 'Hello World' ,   )) ;

Retrieve a Message Returns a Response model - check for Messages array Can implement long polling Queues define a ‘message visibility’ period $this -> awsClient -> receiveMessage ( array (  

‘QueueUrl' => 'http://sqs.us-east-1.amazonaws.com/123456789012/ myQueue' ,   )) ;

Gotchas First in, First out not guaranteed They guarantee ‘at least once’ delivery Retention Periods - default 4 days, max 14 days

Wait… There’s More Security Policies Message Attributes Dead Letter Queues Batch Processing

Thank You Questions?

joind.in/18340 @leesto lee@leestone.co.uk