APP SERVICE
Tags: webdev, javascript, beginners, programming
Published: 2022-10-16 15:23:51

Microsoft developed and maintains Azure Web Apps, a platform for hosting websites based on cloud computing. It is a platform as a service that enables publishing Web applications that use numerous frameworks and were created using a variety of programming languages, including both Microsoft-owned and independent ones. The app service uses HTTP.

**DEFINITION OF TERMS**
1. REST API: Representational State Transfer, sometimes known as REST, is an architectural design for distributed hypermedia systems. It was first introduced in Roy Fielding's renowned dissertation from 2000.
The guiding concepts and limitations of REST are similar to those of other architectural styles. If a service interface wants to be referred to as RESTful, it has to adhere to these standards.
A REST API is a Web API (or Web Service) that adheres to the REST architectural style. 
2. GET: provided resource's representation is requested using the HTTP GET technique. Data should not be included in GET requests; they should only be used to request data. The provided resource's representation is requested using the HTTP GET technique. Data should not be included in GET requests; they should only be used to request data.
3. PUT: The HTTP PUT request method replaces a representation of the target resource with the request payload or creates a new resource. PUT and POST are different in that PUT is idempotent, meaning that calling it once or many times in a row has the same impact (with no side effects), whereas several identical POST requests may have different results, much like placing an order multiple times.
4. POST: Data is sent to the server via the HTTP POST technique. The Content-Type header identifies the type of the request body.
A POST request causes a change on the server and is often sent using an HTML form. In this instance, the content type is chosen by inserting the appropriate string in the enctype attribute of the <form> element or the <input> or <button> components' formenctype attributes.
5. DELETE: The requested resource is deleted using the HTTP DELETE request mechanism.
6. ZIP DEPLOY: When a ZIP package is deployed, App Service unpacks its contents in the app's default path (D:homesitewwwroot for Windows,/home/site/wwwroot for Linux). The same Kudu service that powers continuous integration-based deployments is utilized by this ZIP package deployment.
7. DEPLOYMENT SLOT: New App Services are deployed in slots. This requires you to reinstall any site extensions you previously added to your App Service. Your app service must be priced at least at the Standard tier. A deployment slot cannot be scaled independently from other deployment slots in the App Service.
8. SWAP: In Azure Cloud Services, you can switch between two separate cloud service installations (extended support). The Azure Resource Manager model in Azure Cloud Services (extended support) does not employ deployment slots, in contrast to Azure Cloud Services (traditional). When deploying a new version of a cloud service in Azure Cloud Services (extended support), you can make the cloud service "swappable" with an already-installed cloud service (extended support).
9. ARR AFFIRNITY: By providing the user a unique cookie (known as an affinity cookie), ARR deftly recognizes the user and enables the service to identify the appropriate instance the user was using to fulfill any subsequent requests made by that user.