How to define an OpenAPI ordered array of different objects? - swagger

Question

I am trying to define my API using OpenAPI version 3.0. I am trying to generate a YAML file which has four maps, and each map contains a different information. How can I create a YAML file to achieve that goal? I know that my components are not right because of which I am not getting the right result.
Request body should be like this:
[
UserInformation{FirstName, LastName},
AddressInformation{Phone, Address},
ContactInformation{Email, Phone}
]
openapi: 3.0.0
info:
version: 1.0.0
title: 'INPUT-FORM-API'
paths:
/api/v1/test/healthcheck:
get:
summary: Health check for the test api services. Used Internally
operationId: Externalhealthcheck
description: healthcheck for the test services status.
responses:
'200':
description: This status is always returned when service is Ok.
content:
application/json:
schema:
$ref: '#/components/schemas/HealthcheckObject'
/api/v1/test/newformentry:
post:
summary: End Point to insert data into the new table.
operationId: NewFormEntry
description: EndPoint to insert data for new form.
requestBody:
content:
application/json:
schema:
items:
$ref: '#/components/schemas/NewFormEntry'
responses:
'200':
description: This status is always returned when service is Ok.
content:
application/json:
schema:
$ref: '#/components/schemas/HealthcheckObject'
components:
schemas:
NewFormEntry:
$ref: '#/components/schemas/UserInformation'
$ref: '#/components/schemas/AddressInformation'
$ref: '#/components/schemas/ContactInformation'
$ref: '#/components/schemas/MessageFromBene'
UserInformation:
required:
- FirstName
- LastName
properties:
FirstName:
type: string
LastName:
type: string
AddressInformation:
required:
- StreetAddress
- City
- State
- ZipCode
properties:
StreetAddress:
type: string
StreetAddress2:
type: string
City:
type: string
State:
type: string
ZipCode:
type: integer
format: int64
ContactInformation:
required:
- PhoneNumber
- Email
properties:
PhoneNumber:
type: integer
format: int64
maximum: 9
Email:
type: string
HomePhone:
type: integer
format: int64
maximum: 9
Cell:
type: integer
format: int64
maximum: 9
WorkPhone:
type: integer
format: int64
maximum: 9
MessageFromBene:
required:
- Message
properties:
PhoneNumber:
type: integer
format: int64
maximum: 9
Message:
type: string
HealthcheckObject:
required:
- Status
- ErrorMessage
properties:
Status:
type: string
ErrorMessage:
type: string

Answer 1

So the NewFormEntry schema must be an array containing 3 objects, where the 1st object must be UserInformation, the second object must be AddressInformation, and the 3rd object mube be ContactInformation. This is like a tuple, i.e. an ordered sequence of elements where each element has a specfic type. Tuple definitions are slightly different in different OpenAPI versions.
OpenAPI 3.1
If or when you migrate to OAS 3.1, such an array can be defined using prefixItems. This keyword specifies the schema for each element position (in other words, it specifies the order of elements in the array):
components:
schemas:
NewFormEntry:
type: array
prefixItems:
- $ref: '#/components/schemas/UserInformation' # type of the 1st element
- $ref: '#/components/schemas/AddressInformation' # type of the 2nd element
- $ref: '#/components/schemas/ContactInformation' # type of the 3rd element
minItems: 3
maxItems: 3
additionalItems: false # can be omitted if `maxItems: 3` is specified
OpenAPI 3.0
In OAS 3.0, you can define the array length (i.e. 3 items) and the possible types of array items (i.e. each item can be either A, B, or C), but there's no way to define a specific order of objects in the array. So the most you can do is this:
components:
schemas:
NewFormEntry:
type: array
items:
oneOf:
- $ref: '#/components/schemas/UserInformation'
- $ref: '#/components/schemas/AddressInformation'
- $ref: '#/components/schemas/ContactInformation'
minItems: 3
maxItems: 3
Note that this definition allows arbitrary order of objects in the array and also multiple instances of the same object (e.g. [UserInformation, UserInformation, UserInformation]). You might want to implement additional backend validations to verify the desired order of objects in this array.