Amazon Simple Queue Service (Amazon SQS)
Amazon SQS is a fast,reliable,scalable,and fully managed message queuing service.Amazon SQS makes it simple and cost effective to decouple the components of a cloud application
Amazon SQS is a web service that gives you access to a message queue that can be used to store messages while waiting for a computer to process them.
A queue is a temporary repository for messages that are awaiting processing.
An Amazon SQS queue is basically a buffer between the application components that receive data and those components that process the data in your system.
Messages can contain up to 256 KB of text in any format.
Amazon SQS ensures delivery of each message atleast once,and supports multiple readers and writers interacting with the same queue.
Message Retention period is 14 Days
Amazon SQS is engineered to provide”atleast once“delivery of all messages in its queues. Although most of the time each message will be delivered to your application exactly once.
A single queue can be used simultaneously by many distributed application components, with no need for those components to coordinate with each other to share the queue.
Maximum message size 256 kb now available
AWS will Billed as Chunks,Each Chunk size is 64 kb,That means a 256 kb message will be 4 x 64 kb”chunks”.
First 1 million Amazon SQS Requests per month are free
$0.50 per 1 million Amazon SQS Requests per month there after($0.00000050 per SQS Request)
A single request can have from 1 to10 messages,up to a maximum total payload of 256 KB
Each 64 KB’chunk’of payload is billed as 1 request. For example,a single API call with a 256 KB payload will be billed as four requests.
For example,suppose that you have a web app that receives orders from customers.The app runs on EC2 instances in an Auto Scaling group that is configured to handle a typical number of orders. The app places the orders in an Amazon SQS queue until they are picked up for processing, processes the orders,and then sends the processed orders back to the customer.The following diagram illustrates the architecture of this example.
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.
Using Amazon SQS, you can store application messages on reliable and scalable infrastructure,enabling you to move data between distributed components to perform different tasks as needed.
Amazon SQS ensures delivery of each message at least once and supports multiple readers and writers interacting with the same queue.A single queue can be used simultaneously by many distributed application components,with no need for those components to coordinate with one another to share the queue.Although most of the time each message will be delivered to your application exactly once,you should design your system to be idempotent SQL service does not guarantee First In,First Out(FIFO) delivery of messages.
Amazon SQS supports up to 12 hours’ maximum visibility timeout.
When creating a new queue,you must provide a queue name that is unique with in the scope of all of your queues. Amazon SQS as signs each queue an identifier called a queue URL,which includes the queue name and other components that Amazon SQS determines.Whenever you want to perform an action on a queue,you must provide its queue URL.
To create a Queue,Navigate to“Messaging”section and select the“Simple Queue Service”.
Here is the default values we are getting with the Queue.
Amazon Simple Workflow Service (Amazon SWF)
Amazon Simple Workflow Service(Amazon SWF) is a web service that makes it easy to coordinate work across distributed application components.
Amazon SWF enables applications for a range of use cases,including media processing,web application back-ends, business process workflows, and analytics pipelines, to be designed as a coordination of tasks.
Amazon SWF makes it easy to build applications that coordinate work across distributed components.In Amazon SWF,a task represents a logical unit of work that is performed by a component of your application.
Amazon SWF gives you full control over implementing and coordinating tasks with out worrying about underlying complexities such as tracking their progress and maintaining their state.
We have three SWF Actors:
Workflow Starters-An application that can initiate(start)a work flow.Could be your e-commerce website when placing an order.
Deciders-Control the flow of activity tasks in a workflow execution.If something has finished in a workflow(or fails)a Decider decides what to do next.
Activity Workers-Carry out the activity tasks
Amazon Simple Notification Service (Amazon SNS)
Amazon Simple Notification Service(Amazon SNS)is a web service that makes it easy to setup, operate,and send notifications from the cloud.
It provides developers with a highly scalable, flexible, and cost-effective capability to publish messages from an application and immediately deliver them to subscribers or other applications.
Push notifications to Apple,Google,Fire OS,and Windows devices,as well as Android devices in China with Baidu Cloud Push.
Amazon SNS consists of two types of clients:publishers and subscribers(sometimes known as producers and consumers).
Publishers communicate to subscribers a synchronously by sending a message to a topic.
A topic is simply a logical access point/communication channel that contains a list of subscribers and the methods used to communicate to them.
When you send a message to a topic,it is automatically forwarded to each subscriber of that topic using the communication method configured for that subscriber.
Besides pushing cloud notifications directly to mobile devices,Amazon SNS can also deliver notifications by SMS text message or email,to Amazon Simple Queue Service(SQS)queues,or to any HTTP endpoint.
To prevent messages from being lost, all messages published to Amazon SNS are stored redundantly across multiple availability zones.
SNS allows you to group multiple recipients using topics.A topic is an”access point”for allowing recipients to dynamically subscribe for identical copies of the same notification.
Application and System Alerts
Application and system alerts are SMS and/or email notifications that are triggered by predefined thresholds.For example,we can receive immediate notification when an event occurs,such as a specific change to your Auto Scaling group in AWS.
Push Email and Text Messaging
Push email and text messaging are two ways to transmit messages to individuals or groups via email and/or SMS.For example,you can use Amazon SNS to push targeted news headlines to subscribers by email or SMS. Upon receiving the email or SMS text,interested readers can then choose to learn more by visiting a website or launching an application.
Mobile Push Notifications
Mobile push notifications enable you to send messages directly to mobile applications.For example, you can use Amazon SNS for sending notifications to an application,indicating that an update is available.The notification message can include a link to download and install the update.
More Information :https://www.fgrade.com/aws/