PUT and POST are two commonly used methods, but they serve different purposes and have distinct characteristics.
Key Differences Between PUT and POST
Purpose:
- POST: Used to create a new resource on the server.
- PUT: Used to update an existing resource or create a resource if it does not exist.
Idempotency:
- POST: Not idempotent. Multiple POST requests will create multiple resources.
- PUT: Idempotent. Multiple PUT requests with the same data will produce the same result as a single request.
Usage:
- POST: Typically used to submit data to be processed to a specified resource. It creates a new resource as a subordinate of the specified resource.
- PUT: Typically used to update a resource or create it if it doesn't exist. It replaces the current representation of the resource with the request payload.
Example Scenarios
Example 1: Creating a New Resource with POST
Scenario:
You have a collection of users, and you want to add a new user to this collection.
Request:
POST /users Content-Type: application/json {"name": "John Doe",
"email": "john.doe@example.com"
}
Explanation:
- POST creates a new user as a subordinate of the /users resource.
- The server generates a unique ID for the new user and returns it in the response.
Example 2: Updating an Existing Resource with PUT
Scenario:
You want to update the information of an existing user with ID 123.
Request:
PUT /users/123 Content-Type: application/json {"name": "John Doe",
"email": "john.doe@newdomain.com"
}
Explanation:
- PUT updates the user with ID 123.
- If the user with ID 123 does not exist, PUT can create a new user with this ID and the provided data.