What is Serverless Web Application Development? What is Serverless architecture? Why Serverless architecture? What is AWS Lambda? What is serverless deployment?
What is Serverless Web Application Development? Serverless web application development is an emerging trend that’s gaining immense popularity. The term Serverless itself sounds confusing as it is not possible to run a web application without servers so what does it actually mean.
What is Serverless Application Development?
Although the use of this confusing term seems a marketing trick to intrigue the curious minds from a different perspective, it is a crystal-clear meaningful term.
What is Serverless Architecture?
Serverless architecture means the use of computing runtimes, also known as function as a service (FaaS)platforms, which execute application logic but do not store the data. The model offers a completely different economic model of “Pay as you Go” instead of the conventional ways of renting servers and setting up server instances to deploy the code.
Serverless Architecture is the base of serverless computing, a cloud-computing execution model in which the cloud provider runs the server and dynamically manages the allocation of machine resources. Pricing is based on the actual amount of resources consumed by an application, rather than on pre-purchased units of hardware capacity.
Read: "What is an API and How it works?"
Serverless computing can simplify the process of deploying code into production. Scaling, capacity planning and maintenance operations may be hidden from the developer or operator. Serverless code can be used in conjunction with previously deployed code in traditional styles, such as microservices.
Why Serverless Architecture?
Serverless architecture offers “Pay as you Go” model which is perfect for code where you have to just send simple responses to IOT devices or upload an image or a document.
The function as a service (FaaS) platform offers dynamic scalability of machine resources in runtime.
In runtime function as a service, the platform finds empty instances on the cloud to run the code when a response is requested from client machines. Hence there is high latency in this architecture so it should not be used to a whole web application.
Serverless architecture is best for hosting functions that require high computation power like OCR engines, K-MAP solvers and Linear programming solvers.
To put this, in other words, the part of code for which you require a response or solution even if a billion user simultaneously request that code then you must host that code in serverless architecture in conjunction with rest of the code running on a separate server instance.
What is AWS Lambda?
AWS Lambda with maximum features availability is the best function as a service platform as of the writing of this article. AWS Lambda has gigantic competitors Google Cloud Functions, Microsoft Azure Functions, OpenWhisk by IBM Cloud Functions, Project Riff and Oracle Fn Project.
Behind the curtains, every AWS service invokes AWS Lambda web service API to serve distinct server instances running different AWS services like S3 bucket, DynamoDB, EC2 instance. Now AWS has given access to users on this API which has allowed them to perform tasks on a lower level like hosting the code of an API without even configuring new server instance. The APIs code when run it searches and claims empty server instances to host the API.
AWS Lambda can be controlled through its web application console and the code, the Admin can manage the access of users. AWS Lambda function can be invoked in 4 ways as following:
1. Invoking in response to an event
When an event happens in other AWS services on connected server instances then the code on AWS Lambda can be invoked. Following are the examples of events occurring on AWS hosted code:
Object creation in S3 bucket.
Creation of new index on the elastic search EC2 instance.
State of change in entries on DynamoDB.
The arrival of new messages on Kinesis.
Invocation of Amazon Rekognition.
2. Configuring AWS Lambda gateway to a route HTTP request to Lambda.
3. Invoking through AWS Lambda web service API by parsing JSON
4. Periodic Invocation of AWS Lambda with job scheduler mechanism
What is Serverless Deployment?
Serverless deployment is using the default virtual machine of cloud servers to save and configure the code. The code components which have unpredictable computational costs are usually hosted on serverless platforms in conjunction to the rest of the code hosted on single or multiple server instances depending on the code architecture.