Methods

The HTTP verbs comprise our “uniform interface” and provide us with the action counterpart to noun-based resources. The most-commonly-used verbs (or methods) are POST, GET, PUT, PATCH, and DELETE. These correspond to create, read, update, and delete (or CRUD) operations, respectively.

HEAD

The HEAD method is used to request HTTP headers from the server. The HEADrequest is identical to the GETrequest except that the server must not return the message body in the response. Requests using the HEAD method will only retrieve data and are considered safe.

// Request:

HEAD /echo/head/json HTTP/1.1
Accept: application/json
Host: api.bank.tech

// Response from host:

HTTP/1.1 200 OK
Content-Length: 19
Content-Type: application/json

You should fetch the headers of each method you intend to use to familiarise yourself with the expected structure of the header for the method you intend to make use of.

Since BankTech uses a bearer token authentication scheme, your header request will always include:

// Request:

POST http://www.example.com/customers HTTP/1.1
Host: example.com
Authorization: Bearer AbCdEf123456
Content-Type: application/json

GET

The GET verb is used to retrieve a representation of a resource. According to the design of the HTTP specification, GET (along with HEAD) requests are used only to read data and not change it. Requests using the GETmethod will only retrieve data and are considered safe.

GET http://www.example.com/customers/12345

POST

The POST verb is most often utilized to create new resources. In particular, it's used to create subordinate resources. That is, subordinate to some other (e.g. parent) resource. Making two identical POST requests will most likely result in two resources containing the same information.

POST http://www.example.com/customers

[
  {
    "objectId": 1,
    "firstName": "John",
    "lastName": "Smith",
    "accountID": "12345"    
  }
]

PUT

The PUT verb is most-often utilized for update capabilities, PUT-ing to a known resource with the request body containing the newly-updated version of the original resource. However, PUT can also be used to create a resource in the case where the resource ID is chosen by the client instead of by the server.

PUT http://www.example.com/customers/12345

[
  {
    "objectId": 1,
    "firstName": "Sarah",
    "lastName": "Jones",
    "accountID": "54321"    
  }
]

PATCH

The PATCH verb is used for modify capabilities. The PATCH request only needs to contain the changes to the resource, not the complete resource. This resembles PUT, but the body contains a set of instructions describing how a resource on the server should be modified to produce a new version.

PATCH http://www.example.com/customers/54321

[
  {
    "objectId": 1,
    "firstName": "Sarah",
    "lastName": "Smith"
  }
]

DELETE

The DELETE verb is pretty easy to understand. It is used to delete a resource identified. HTTP-spec-wise, DELETE operations are idempotent. If you DELETE a resource, it is removed. Repeatedly calling DELETE on that resource ends up with the same result: the resource is already gone.

DELETE http://www.example.com/customers/54321