A REST API (Representational State Transfer Application Programming Interface) is an architectural style that defines a set of rules and constraints for creating web services. Think of it as a translator that allows different software applications to communicate with each other over the internet, typically using the HTTP protocol. It’s a common way for client applications (like a mobile app or a website) to request and manipulate data from a server.
HTTP Methods
GET
- Purpose: To retrieve or “get” data from a server.
- Data Location: Data is appended to the URL as query parameters (e.g.,
www.example.com/users?id=123). - Characteristics:
- Idempotent: Making the same GET request multiple times produces the same result.
- Visible Data: Since data is in the URL, it’s visible in browser history and server logs, making it insecure for sensitive information like passwords.
- Limited Length: The length of a URL is limited, so you can only send a small amount of data.
- Can be bookmarked and cached.
POST
- Purpose: To send data to a server to create a new resource (e.g., creating a new user account).
- Data Location: Data is sent in the body of the HTTP request, hidden from the URL.
- Characteristics:
- Not Idempotent: Making the same POST request multiple times will create multiple new resources.
- Secure Data: Data is not exposed in the URL, making it suitable for sensitive or large amounts of data.
- No Length Limit: Can send much more data than a GET request.
- Cannot be bookmarked or cached.
PUT
Replaces an existing resource entirely with the data provided. If the resource doesn’t exist, it can create it. It is idempotent.
PATCH
Applies a partial modification to an existing resource. For example, updating only a user’s email address without changing their other details.
DELETE
Removes a specific resource from the server.
HEAD
Similar to a GET request, but it only returns the response headers and not the actual data (the body). It’s useful for quickly checking a resource’s metadata, like its size or last modified date, without downloading the content.
OPTIONS
Describes the communication options (i.e., which HTTP methods are allowed) for the target resource