How to define array-of-objects as parameter? - yaml

Question

I am quite new to Swagger, so this might be a basic question.
I am able to create .yml file for an API which takes an array of integers as parameter, as follows:
Add samples
---
tags:
- MY API
parameters:
- name: my_id
in: path
type: integer
required: true
description: Some des
- name: body
in: body
schema:
id: add_samples
required:
- sample_ids
properties:
sample_ids:
type: array
items:
type: integer
description: A list of sample ids to be added
responses:
'200':
description: Added samples.
'400':
description: Error adding samples.
This is what I send to the above API and everything works fine:
{"sample_ids": [475690,475689,475688]}
Now, instead of an array of integers, if I want to use some complex object as parameter, how to do it?
E.g. If this is what I want to send:
{"sample_ids": [{
"sample_id": "7",
"some_prop": "123"
},
{
"sample_id": "17",
"some_prop": "134"
}]}
How should the .yml file look? I have tried something like this and it doesn't seem to work:
Add sample
---
tags:
- Samples API
models:
Sample:
id: Sample
properties:
sample_id:
type: string
default: ""
description: The id for this sample
some_prop:
type: integer
description: Some prop this sample
parameters:
- name: body
in: body
schema:
id: add_sample
required:
- sample_ids
properties:
samples:
type: array
description: A list of samples to be added
items:
$ref: Sample
responses:
'201':
description: Created a new sample with the provided parameters
'400':
description: SOME ERROR CODE

Answer 1

This one seems to work, mostly:
Add sample
---
tags:
- Samples API
models:
Sample:
id: Sample
properties:
sample_id:
type: string
default: ""
description: The id for this sample
some_prop:
type: integer
description: Some prop this sample
parameters:
- name: body
in: body
schema:
id: add_sample
required:
- sample_ids
properties:
samples:
type: array
description: A list of samples to be added
items:
$ref: Sample
responses:
'201':
description: Created a new sample with the provided parameters
'400':
description: SOME ERROR CODE
Now only problem is, in the Swagger UI, it is not showing member variables and their default values. Rather is showing it as null:
{
"samples": [
null
]
}