HTTP

Hypertext Transfer Protocol (HTTP) is an application layer protocol in the Internet protocol suite model for distributed, collaborative, hypermedia information systems that lay the foundation of data communication for the World Wide Web.

Index

• Methods
• Headers
• REST

Methods

HTTP methods (verbs) indicate the desired action to be performed on the identified resource.

• GET method requests that the target resource transfer a representation of its state, it should only retrieve data and should have no other effect.
• POST method requests that the target resource process the representation enclosed in the request according to the semantics of the target resource.
• PUT method requests that the target resource create or update its state with the total state defined by the representation enclosed in the request.
• PATCH method requests that the target resource modify its state according to the partial update defined in the representation enclosed in the request.
• DELETE method requests that the target resource delete its state.

Headers

HTTP headers are a list of strings sent and received by both the client program and server on every HTTP request and response.

Authorization

Authorization is used to provide credentials that authenticate a user agent with a server, allowing access to protected resources.

Authorization: Basic <base64(username:password)>
Authorization: Bearer <token>
Authorization: ApiKey <base64(api_key:secret_key)>

Content-Disposition

Content-Disposition describes what the receiver should do with the content, should it be displayed in the browser or downloaded as a file.

Content-Disposition: [inline|attachment]; filename="[filename]"

• inline specifies that the file should be displayed in the browser.
• attachment specifies that the file should be downloaded.
• filename specifies what downloaded file should be named.

This header is commonly used with a HTML anchor element to download a file from a URL.

const link = document.createElement('a');
link.target = '_blank';
link.href = url;
link.download = filename;
link.click();

REST

Representational State Transfer (REST) is a software architectural style that was created to guide the design and development of the architecture for the World Wide Web. It has been employed throughout the software industry to create stateless, idempotent and reliable Web-based applications and HTTP-based APIs.

• Use plural noums to represent collection of resources.

/customers/{id}
/customers/{id}/orders
/store/items/{id}

• Use hyphens instead of underscores.

/store/inventory-management

• Versioning.

/v1/customers/{id}
/v2/customers/{id}

• Filtering.

/customers?lastname=Smith&age=63
/customers?fields=id,age

• Sorting.

/customers?sort=lastname,age

• Pagination.

/customers?limit=50
/customers?start=0&limit=50