# Create a context field

POST https://app.unleash-instance.example.com/api/admin/context
Content-Type: application/json

Endpoint that allows creation of [custom context fields](https://docs.getunleash.io/concepts/unleash-context#custom-context-fields)

Reference: https://docs.getunleash.io/api/create-context-field

## OpenAPI Specification

```yaml
openapi: 3.1.1
info:
  title: Create a context field
  version: endpoint_context.createContextField
paths:
  /api/admin/context:
    post:
      operationId: create-context-field
      summary: Create a context field
      description: >-
        Endpoint that allows creation of [custom context
        fields](https://docs.getunleash.io/concepts/unleash-context#custom-context-fields)
      tags:
        - - subpackage_context
      parameters:
        - name: Authorization
          in: header
          description: Header authentication of the form `undefined <token>`
          required: true
          schema:
            type: string
      responses:
        '201':
          description: The resource was successfully created.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/contextFieldSchema'
      requestBody:
        description: createContextFieldSchema
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/createContextFieldSchema'
components:
  schemas:
    legalValueSchema:
      type: object
      properties:
        value:
          type: string
          description: The valid value
        description:
          type: string
          description: Describes this specific legal value
      required:
        - value
    createContextFieldSchema:
      type: object
      properties:
        description:
          type: string
          description: A description of the context field
        stickiness:
          type: boolean
          description: >-
            `true` if this field should be available for use with [custom
            stickiness](https://docs.getunleash.io/concepts/stickiness#custom-stickiness),
            otherwise `false`
        sortOrder:
          type: integer
          description: >-
            How this context field should be sorted if no other sort order is
            selected
        legalValues:
          type: array
          items:
            $ref: '#/components/schemas/legalValueSchema'
          description: A list of allowed values for this context field
        project:
          type: string
          description: >-
            The project this context field belongs to (if it is
            project-specific)
        name:
          type: string
          description: The name of the context field.
      required:
        - name
    contextFieldSchema:
      type: object
      properties:
        name:
          type: string
          description: The name of the context field
        description:
          type:
            - string
            - 'null'
          description: The description of the context field.
        stickiness:
          type: boolean
          description: >-
            Does this context field support being used for
            [stickiness](https://docs.getunleash.io/concepts/stickiness)
            calculations
        sortOrder:
          type: integer
          description: >-
            Used when sorting a list of context fields. Is also used as a
            tiebreaker if a list of context fields is sorted alphabetically.
        createdAt:
          type:
            - string
            - 'null'
          format: date-time
          description: When this context field was created
        usedInFeatures:
          type:
            - integer
            - 'null'
          description: Number of projects where this context field is used in
        usedInProjects:
          type:
            - integer
            - 'null'
          description: Number of projects where this context field is used in
        legalValues:
          type: array
          items:
            $ref: '#/components/schemas/legalValueSchema'
          description: >-
            Allowed values for this context field schema. Can be used to narrow
            down accepted input
        project:
          type: string
          description: >-
            The project this context field belongs to (if it is
            project-specific)
      required:
        - name

```

## SDK Code Examples

```python
import requests

url = "https://app.unleash-instance.example.com/api/admin/context"

payload = { "name": "subscriptionTier" }
headers = {
    "Authorization": "<apiKey>",
    "Content-Type": "application/json"
}

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

print(response.json())
```

```javascript
const url = 'https://app.unleash-instance.example.com/api/admin/context';
const options = {
  method: 'POST',
  headers: {Authorization: '<apiKey>', 'Content-Type': 'application/json'},
  body: '{"name":"subscriptionTier"}'
};

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://app.unleash-instance.example.com/api/admin/context"

	payload := strings.NewReader("{\n  \"name\": \"subscriptionTier\"\n}")

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

	req.Header.Add("Authorization", "<apiKey>")
	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://app.unleash-instance.example.com/api/admin/context")

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

request = Net::HTTP::Post.new(url)
request["Authorization"] = '<apiKey>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"name\": \"subscriptionTier\"\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://app.unleash-instance.example.com/api/admin/context")
  .header("Authorization", "<apiKey>")
  .header("Content-Type", "application/json")
  .body("{\n  \"name\": \"subscriptionTier\"\n}")
  .asString();
```

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

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'https://app.unleash-instance.example.com/api/admin/context', [
  'body' => '{
  "name": "subscriptionTier"
}',
  'headers' => [
    'Authorization' => '<apiKey>',
    'Content-Type' => 'application/json',
  ],
]);

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

```csharp
using RestSharp;

var client = new RestClient("https://app.unleash-instance.example.com/api/admin/context");
var request = new RestRequest(Method.POST);
request.AddHeader("Authorization", "<apiKey>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"name\": \"subscriptionTier\"\n}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = [
  "Authorization": "<apiKey>",
  "Content-Type": "application/json"
]
let parameters = ["name": "subscriptionTier"] as [String : Any]

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

let request = NSMutableURLRequest(url: NSURL(string: "https://app.unleash-instance.example.com/api/admin/context")! 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()
```