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# Creates a custom field definition.

POST https://api.awork.com/api/v1/customfielddefinitions
Content-Type: application/json

Creates a custom field definition that can be linked to project templates, projects, or tasks according to its entity type.The user must be an admin or have `project-manage-config:write` permissions.

Reference: https://developers.awork.com/apiv1/custom-fields/post-custom-field-definition

## Authentication

- `Authorization` header (bearer token, required) — Bearer authentication of the form `Bearer <token>`, where token is your auth token.

## Request

### Body (application/json)

This endpoint expects a CustomFieldDefinitionPostForm.

- `name` (string, required) — The name of the custom field definition.
- `type` (enum, required) — The type of the custom field definition.
  - Allowed values: `text`, `number`, `date`, `datetime`, `select`, `coloredSelect`, `link`, `boolean`, `user`, `client`
- `entity` (enum, required) — The entity the custom field definition can be linked to.
  - Allowed values: `task`, `project`
- `selectionOptions` (list of CustomFieldSelectionOptionsForm, optional, nullable) — The selection options for the custom field definition. Can only be used if the type is 'select'.
- `order` (double, optional, nullable) — The order of the custom field definition. This value is only used (and required) if the entity is 'project', as the project custom field definitions are globally ordered. To set the order for task custom field definitions, use the endpoint to update the order of a custom field definition for a project/project template.

## Response

### 200

OK

- `id` (string, optional) — The id of the custom field definition.
- `name` (string, optional, nullable) — The name of the custom field definition.
- `entity` (enum, optional) — The entity the custom field definition can be linked to.
  - Allowed values: `task`, `project`
- `type` (enum, optional) — The type of the custom field definition.
  - Allowed values: `text`, `number`, `date`, `datetime`, `select`, `coloredSelect`, `link`, `boolean`, `user`, `client`
- `createdOn` (string, optional) — The date this entity was created.
- `createdBy` (string, optional) — The id of the user who created this entity.
- `updatedOn` (string, optional) — The date this entity was last modified.
- `updatedBy` (string, optional) — The id of the user who last modified this entity.
- `order` (double, optional, nullable) — If it's a project custom field, it's the global order of the custom field definition. Otherwise, it's the order of the custom field definition within a project template or a project.
- `isExternal` (boolean, optional) — True if this entity is coming from an external workspace (awork Connect).
- `selectionOptions` (list of CustomFieldSelectionOption, optional, nullable) — The selection options for this custom field definition.

## Errors

### 400 Bad Request Error

Bad Request

- `code` (string, required) — The error code.
- `description` (string, required) — The description of the error.
- `link` (string, required) — The link to the API documentation page.
- `details` (list of string, optional, nullable) — A list of details describing the error.
- `validationErrors` (list of ValidationErrorResponse, optional, nullable) — If a validation error occurred, this contains the validation errors for each property.
- `traceId` (string, optional, nullable) — The request trace id for tracking the request.

## Types

### CustomFieldSelectionOptionsForm

- `value` (string, required) — The selection value which can be used in a select custom field.
- `order` (double, required) — The order of the custom field selection option.
- `color` (enum, optional, nullable) — The color of the selection option.
  - Allowed values: `red`, `orange`, `yellow`, `green`, `cyan`, `blue`, `indigo`, `purple`, `steel`

### CustomFieldSelectionOption

- `value` (string, required) — The selection value which can be later used in a select custom field.
- `id` (string, optional) — The id of the custom field selection option.
- `color` (enum, optional, nullable) — The color of the selection option.
  - Allowed values: `red`, `orange`, `yellow`, `green`, `cyan`, `blue`, `indigo`, `purple`, `steel`
- `order` (double, optional) — The order of the custom field selection option.

### ValidationErrorResponse

The validation error response.

- `property` (string, optional, nullable) — The name of the property that failed validation.
- `message` (string, optional, nullable) — The reason why this property failed validation.

## Examples

**Request**

```json
{
  "name": "Ticket-Number",
  "type": "text",
  "entity": "task"
}
```

**Response**

```json
{
  "id": "123e4567-e89b-12d3-a456-426614174000",
  "name": "Ticket-Number",
  "entity": "task",
  "type": "text",
  "createdOn": "2022-03-10T16:25:09.100Z",
  "createdBy": "123e4567-e89b-12d3-a456-426614174000",
  "updatedOn": "2022-03-10T18:55:00.500Z",
  "updatedBy": "123e4567-e89b-12d3-a456-426614174000",
  "order": 1,
  "isExternal": true,
  "selectionOptions": [
    {
      "value": "Website Design",
      "id": "123e4567-e89b-12d3-a456-426614174000",
      "color": "purple",
      "order": 0
    }
  ]
}
```

**SDK Code**

```python
import requests

url = "https://api.awork.com/api/v1/customfielddefinitions"

payload = {
    "name": "Ticket-Number",
    "type": "text",
    "entity": "task"
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.json())
```

```javascript
const url = 'https://api.awork.com/api/v1/customfielddefinitions';
const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: '{"name":"Ticket-Number","type":"text","entity":"task"}'
};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}
```

```go
package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.awork.com/api/v1/customfielddefinitions"

	payload := strings.NewReader("{\n  \"name\": \"Ticket-Number\",\n  \"type\": \"text\",\n  \"entity\": \"task\"\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(res)
	fmt.Println(string(body))

}
```

```ruby
require 'uri'
require 'net/http'

url = URI("https://api.awork.com/api/v1/customfielddefinitions")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"name\": \"Ticket-Number\",\n  \"type\": \"text\",\n  \"entity\": \"task\"\n}"

response = http.request(request)
puts response.read_body
```

```java
import com.mashape.unirest.http.HttpResponse;
import com.mashape.unirest.http.Unirest;

HttpResponse<String> response = Unirest.post("https://api.awork.com/api/v1/customfielddefinitions")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"name\": \"Ticket-Number\",\n  \"type\": \"text\",\n  \"entity\": \"task\"\n}")
  .asString();
```

```php
<?php
require_once('vendor/autoload.php');

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'https://api.awork.com/api/v1/customfielddefinitions', [
  'body' => '{
  "name": "Ticket-Number",
  "type": "text",
  "entity": "task"
}',
  'headers' => [
    'Authorization' => 'Bearer <token>',
    'Content-Type' => 'application/json',
  ],
]);

echo $response->getBody();
```

```csharp
using RestSharp;

var client = new RestClient("https://api.awork.com/api/v1/customfielddefinitions");
var request = new RestRequest(Method.POST);
request.AddHeader("Authorization", "Bearer <token>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"name\": \"Ticket-Number\",\n  \"type\": \"text\",\n  \"entity\": \"task\"\n}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = [
  "Authorization": "Bearer <token>",
  "Content-Type": "application/json"
]
let parameters = [
  "name": "Ticket-Number",
  "type": "text",
  "entity": "task"
] as [String : Any]

let postData = JSONSerialization.data(withJSONObject: parameters, options: [])

let request = NSMutableURLRequest(url: NSURL(string: "https://api.awork.com/api/v1/customfielddefinitions")! as URL,
                                        cachePolicy: .useProtocolCachePolicy,
                                    timeoutInterval: 10.0)
request.httpMethod = "POST"
request.allHTTPHeaderFields = headers
request.httpBody = postData as Data

let session = URLSession.shared
let dataTask = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
  if (error != nil) {
    print(error as Any)
  } else {
    let httpResponse = response as? HTTPURLResponse
    print(httpResponse)
  }
})

dataTask.resume()
```