The field-optiongroup API from Castor — 3 operation(s) for field-optiongroup.
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openapi: 3.2.0
info:
version: 2026.1.6.1
title: Castor EDC API Documentation Field Optiongroup API
description: '### Overview
This document provides the specifications of the Castor EDC API, describing the currently available
API endpoints and methods. We aim to provide a fully functional RESTful API to communicate with
Castor EDC and these are endpoints currently available.
The formal OpenAPI 2 specification by which this page is rendered is also available in the following formats:
* YAML
* JSON
* JSON (pretty print)
### Authentication & Authorization with OAuth 2
Authentication and authorization are arranged through OAuth2. We currently provide full support for the Client
Credentials flow. The Authorization Code flow is supported, but we ask you to contact us if you want to use this flow.
To use the Client Credentials flow go to your
Castor EDC profile and generate
a Client ID and Client Secret. Use the Client ID and Client Secret to retrieve an access token by making a request to
the ''/oauth/token'' endpoint with your client_id and client_secret as parameters and grant_type=client_credentials.
PHP Example:
```php
include __DIR__.''/vendor/autoload.php'';
use Guzzle\Http\Client;
// Create the HTTP Client.
$httpClient = new Client(
''https://data.castoredc.com'',
[
''request.options'' => [
''exceptions'' => false,
]
]
);
// Build the request
$request = $httpClient->post(
''/oauth/token'',
null,
[
''client_id'' => ''YourCastorClientId'',
''client_secret'' => ''YourCastorClientSecret'',
''grant_type'' => ''client_credentials'',
]
);
// Send the request
$response = $request->send();
$responseBody = $response->getBody(true);
$responseArr = json_decode($responseBody, true);
$accessToken = $responseArr[''access_token''];
```
In your subsequent requests you can use the `$accessToken` as a Bearer token in the Authorization header, i.e:
```php
$request = $httpClient->get(''/api/user'');
$request->addHeader(''Authorization'', ''Bearer ''. $accessToken);
$response = $request->send();
echo $response->getBody();
```
### OAuth2 Scopes
There are 3 scopes that endpoints may support.
* **default**: allows access to all endpoints
* **study_statistics**: allows access to study statistics
* **record**: allows access to data for a single participant
Due to a bug in the OpenAPI UI, all three scopes are listed for all endpoints.
If the endpoint supports something other than the default scope, the summary will have a 🔭 emoji and the scope will be
listed in the description as well as under the `security:` key in the specification.
### Rate Limits
Unless specified in the resource, endpoints are rate-limited to 600 requests in 10 minutes.
### Legacy (Basic HTTP Authentication)
**Please note: Basic HTTP Authentication has been removed on 2019 August 13**
### Changelog
API changes can be viewed here'
contact:
name: support@castoredc.com
servers:
- url: https://data.castoredc.com/api/
security:
- OAuth2ClientCredentials:
- default
- study_statistics
- record
tags:
- name: field-optiongroup
paths:
/study/{study_id}/export/optiongroups:
get:
tags:
- field-optiongroup
summary: Export the study's option groups with all option details
security:
- OAuth2ClientCredentials:
- default
description: Returns a string with the study's option groups and options in unified, flat CSV format.
parameters:
- name: study_id
in: path
description: The ID of the study for which this call should be made
required: true
schema:
type: string
format: UUID
responses:
200:
description: The study's option groups with the header and content.
content:
text/csv:
schema:
title: Option Groups flat export representation
type: string
$ref: '#/components/schemas/OptionGroups'
403:
description: Forbidden
content:
text/csv:
schema:
$ref: '#/components/schemas/Error'
406:
description: Not Acceptable
content:
text/csv:
schema:
$ref: '#/components/schemas/Not_Acceptable'
default:
description: Unexpected error
content:
text/csv:
schema:
$ref: '#/components/schemas/Error'
operationId: getStudyByStudyIdExportOptiongroups
x-operation-id-source: derived
/study/{study_id}/field-optiongroup:
get:
tags:
- field-optiongroup
summary: Retrieves the list of all available FieldOptionGroups
security:
- OAuth2ClientCredentials:
- default
description: 'Gets `FieldOptionGroup` objects.
Always requires a study_id to be given. Can be paged.
Returns HalJson responses (with _links for paging and to single objects).'
parameters:
- name: study_id
in: path
description: The ID of the study for which this call should be made
required: true
schema:
type: string
format: UUID
- name: page
in: query
description: The page to retrieve
required: false
schema:
type: integer
default: 1
responses:
200:
description: List of all fields of the Study
content:
application/hal+json:
schema:
title: FieldOptionGroup HalJSON representation
type: object
properties:
_links:
$ref: '#/components/schemas/LinksCollection'
_embedded:
type: object
properties:
fieldOptionGroups:
type: array
items:
$ref: '#/components/schemas/FieldOptionGroup'
page_count:
type: number
page_size:
type: number
total_items:
type: number
page:
type: number
default:
description: Unexpected error
content:
application/hal+json:
schema:
$ref: '#/components/schemas/Error'
operationId: getStudyByStudyIdFieldOptiongroup
x-operation-id-source: derived
/study/{study_id}/field-optiongroup/{optiongroup_id}:
get:
tags:
- field-optiongroup
summary: Retrieve a single FieldOptionGroup
security:
- OAuth2ClientCredentials:
- default
description: Returns HalJson objects (with _links).
parameters:
- name: study_id
in: path
description: The ID of the study for which this call should be made
required: true
schema:
type: string
format: UUID
- name: optiongroup_id
in: path
description: ID of the optiongroup to fetch
required: true
schema:
type: string
responses:
200:
description: Single FieldOptionGroup
content:
application/hal+json:
schema:
$ref: '#/components/schemas/FieldOptionGroup'
default:
description: Unexpected error
content:
application/hal+json:
schema:
$ref: '#/components/schemas/Error'
operationId: getStudyByStudyIdFieldOptiongroupByOptiongroupId
x-operation-id-source: derived
components:
schemas:
FieldOptionGroup:
type: object
properties:
id:
type: string
format: UUID
description: Unique identifier of the FieldOptionGroup
name:
type: string
description: The FieldOptionGroup name
description:
type: string
description: The FieldOptionGroup description
layout:
type: string
description: Horizontal or vertical option positioning
options:
type: array
description: The list of FieldOptions that are included in this FieldOptionGroup
items:
$ref: '#/components/schemas/FieldOption'
_links:
$ref: '#/components/schemas/LinksSingle'
OptionGroups:
properties:
Study ID:
type: string
format: UUID
description: Unique identifier of the Study
Option Group ID:
type: string
format: UUID
description: Unique identifier of the Option Group
Option Group Name:
type: string
description: The Option Group name
Option ID:
type: string
format: UUID
description: Unique identifier of the Option
Option Name:
type: string
description: Option Name
Option Value:
type: string
description: Option Value
LinksCollection:
type: object
properties:
self:
type: object
properties:
href:
type: string
first:
type: object
properties:
href:
type: string
last:
type: object
properties:
href:
type: string
next:
type: object
properties:
href:
type: string
LinksSingle:
type: object
properties:
self:
type: object
properties:
href:
type: string
FieldOption:
type: object
properties:
id:
type: string
format: UUID
description: Unique identifier of the Option
name:
type: string
description: The Option name
value:
type: string
description: The Option value
groupOrder:
type: integer
description: The position of the option within the group
Error:
type: object
properties:
status:
type: integer
format: int32
description: The HTTP return code.
title:
type: string
description: The short error description belonging to the status code
detail:
type: string
description: The detailed explanation of the failure
type:
type: string
description: URL to RFC explaining this statuscode
errors:
type: object
description: Optional list of all errors that occurred during the request
validation_messages:
type: object
description: Optional list of validation failure message
Not_Acceptable:
type: object
properties:
status:
type: integer
format: int32
description: The HTTP return code.
type:
type: string
description: URL to RFC explaining this statuscode
title:
type: string
description: The short error description belonging to the status code
detail:
type: string
description: The detailed explanation of the failure
securitySchemes:
OAuth2ClientCredentials:
type: oauth2
flows:
clientCredentials:
scopes:
default: Grants access to everything
study_statistics: Grants access to a study's statistics
record: Grants access to the data for a single participant; intended for use by study subjects
tokenUrl: https://data.castoredc.com/oauth/token
x-provenance:
method: harvested
publisher: Castor
source: https://data.castoredc.com/api/swagger
note: split by refine-openapis from the provider's own published document, verified by fetch (openapi/_original/*.fetch.json);
stamped by stamp-openapi-provenance.py (roadmap#793)