HTTP methods: GET, POST, PUT, PATCH, DELETE

POST: create a new resource

POST /users
{
    "name": "Alice",
    "age": 20
}

GET: retrieve a resource

GET /users/0
# Result is:
{
    "name": "Alice",
    "age": 20
}

DELETE: delete a resource

DELETE /users/0

PUT: replace or create a entire resource

PUT /users/0
{
    "name": "Alice",
    "age": 25
}

If resource user with id = 0 not exist, this PUT command will behave like POST command.

Because this is replacing, we must specify all attributes in PUT body. Missing attributes will be lost, like this request

PUT /users/0
{
    "age": 25
}

GET /users/0
# Result is:
{
    "age": 20
}

Attribute “name” is lost.

PATCH: replace some attributes of a resource

We use PATCH to change some attributes. Other attributes will remain the same.

PATCH /users/0
{
    "age": 25
}

GET /users/0
# Result is:
{ 
    "name": "Alice", 
    "age": 20
}