Advanced REST scenarios

REST complex objects 

There are two approaches to managing complex objects in REST where we can include the entire object in its operation and/or provide specific paths for each object 

Invoice creation as a whole object

POST /invoice 
{
"invoiceId": 1000,
"invoiceDate": "02/04/2001",
"vendorName": "XYZ Industries Ltd",
"approving Manager": null,
"accountNumber": null
 "address":{
  "streetName":"123 St Kilda Road",
  "suburb": "St Kilda",
  "state":"VIC",
  "postcode":3000
 }
}

Create the subobjects on their own like below 

POST /invoice/1000/address

 "address":{

  "streetName":"123 St Kilda Road",

  "suburb": "St Kilda",
  "state":"VIC",

  "postcode":3000

 }

REST managing state 

Managing the state in REST can be quite challenging. The change in state may trigger different validation and business rules used to process that payload. Rather than using complex logic we could use the resource paths to model the representation of each state. 

Example 

Modifying the pre-approval and post-approval of a workflow item. Below is an invoice that requires approval for payment. 

Invoice creation state 

POST /invoice 
{
"invoiceId": 1000,
"invoiceDate": "02/04/2001",
"vendorName": "XYZ Industries Ltd",
"approving Manager": null,
"accountNumber": null
}

Invoice approval state

PUT /invoice/1000/approval 
{
"invoiceDate": "02/04/2001",
"vendorName": "XYZ Industries Ltd",
"approving Manager": "Tom",
"accountNumber": null
}
   
Invoice payment state

PUT /invoice/1000/payment 
{
"invoiceDate": "02/04/2001",
"vendorName": "XYZ Industries Ltd",
"approving Manager": "Tom",
"accountNumber": 6597465923056
}