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# Create a new segment

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

Creates a new segment using the payload provided

Reference: https://docs.getunleash.io/api/create-segment

## Authentication

- `Authorization` header (required) — API key needed to access this API
- `Authorization` header (bearer token, required) — API key needed to access this API, in Bearer token format

## Request

### Body (application/json)

- `name` (string, required) — The name of the segment
- `constraints` (list of object, required) — The list of constraints that make up this segment
  - `contextName` (string, required) — The name of the context field that this constraint should apply to.
  - `operator` (enum, required) — The operator to use when evaluating this constraint. For more information about the various operators, refer to [the strategy constraint operator documentation](https://docs.getunleash.io/concepts/activation-strategies#constraint-operators).
    - Allowed values: `NOT_IN`, `IN`, `STR_ENDS_WITH`, `STR_STARTS_WITH`, `STR_CONTAINS`, `NUM_EQ`, `NUM_GT`, `NUM_GTE`, `NUM_LT`, `NUM_LTE`, `DATE_AFTER`, `DATE_BEFORE`, `SEMVER_EQ`, `SEMVER_GT`, `SEMVER_LT`, `SEMVER_GTE`, `SEMVER_LTE`, `REGEX`
  - `caseInsensitive` (boolean, optional, default: false) — Whether the operator should be case sensitive or not. Defaults to `false` (being case sensitive).
  - `inverted` (boolean, optional, default: false) — Whether the result should be negated or not. If `true`, will turn a `true` result into a `false` result and vice versa.
  - `values` (list of string, optional) — The context values that should be used for constraint evaluation. Use this property instead of `value` for properties that accept multiple values.
  - `value` (string, optional) — The context value that should be used for constraint evaluation. Use this property instead of `values` for properties that only accept single values.
- `description` (string, optional, nullable) — A description of what the segment is for
- `project` (string, optional, nullable) — The project the segment belongs to if any.

## Response

### 201

The resource was successfully created.

- `id` (integer, required) — The ID of this segment
- `name` (string, required) — The name of this segment
- `constraints` (list of object, required) — The list of constraints that are used in this segment
  - `contextName` (string, required) — The name of the context field that this constraint should apply to.
  - `operator` (enum, required) — The operator to use when evaluating this constraint. For more information about the various operators, refer to [the strategy constraint operator documentation](https://docs.getunleash.io/concepts/activation-strategies#constraint-operators).
    - Allowed values: `NOT_IN`, `IN`, `STR_ENDS_WITH`, `STR_STARTS_WITH`, `STR_CONTAINS`, `NUM_EQ`, `NUM_GT`, `NUM_GTE`, `NUM_LT`, `NUM_LTE`, `DATE_AFTER`, `DATE_BEFORE`, `SEMVER_EQ`, `SEMVER_GT`, `SEMVER_LT`, `SEMVER_GTE`, `SEMVER_LTE`, `REGEX`
  - `caseInsensitive` (boolean, optional, default: false) — Whether the operator should be case sensitive or not. Defaults to `false` (being case sensitive).
  - `inverted` (boolean, optional, default: false) — Whether the result should be negated or not. If `true`, will turn a `true` result into a `false` result and vice versa.
  - `values` (list of string, optional) — The context values that should be used for constraint evaluation. Use this property instead of `value` for properties that accept multiple values.
  - `value` (string, optional) — The context value that should be used for constraint evaluation. Use this property instead of `values` for properties that only accept single values.
- `createdAt` (string, required) — When the segment was created
- `description` (string, optional, nullable) — The description for this segment
- `usedInFeatures` (integer, optional, nullable) — The number of feature flags that use this segment. The number also includes the any flags with pending change requests that would add this segment.
- `usedInProjects` (integer, optional, nullable) — The number of projects that use this segment. The number includes any projects with pending change requests that would add this segment.
- `project` (string, optional, nullable) — The project the segment belongs to. Only present if the segment is a project-specific segment.
- `createdBy` (string, optional, nullable) — The creator's email or username

## Examples

**Request**

```json
{
  "name": "beta-users",
  "constraints": [
    {
      "contextName": "appName",
      "operator": "IN"
    }
  ]
}
```

**Response**

```json
{
  "id": 2,
  "name": "ios-users",
  "constraints": [
    {
      "contextName": "appName",
      "operator": "IN",
      "caseInsensitive": false,
      "inverted": false,
      "values": [
        "my-app",
        "my-other-app"
      ],
      "value": "my-app"
    }
  ],
  "createdAt": "2023-04-12T11:13:31.960Z",
  "description": "IOS users segment",
  "usedInFeatures": 3,
  "usedInProjects": 2,
  "project": "red-vista",
  "createdBy": "someone@example.com"
}
```

**SDK Code**

```python
import requests

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

payload = {
    "name": "beta-users",
    "constraints": [
        {
            "contextName": "appName",
            "operator": "IN"
        }
    ]
}
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/segments';
const options = {
  method: 'POST',
  headers: {Authorization: '<apiKey>', 'Content-Type': 'application/json'},
  body: '{"name":"beta-users","constraints":[{"contextName":"appName","operator":"IN"}]}'
};

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/segments"

	payload := strings.NewReader("{\n  \"name\": \"beta-users\",\n  \"constraints\": [\n    {\n      \"contextName\": \"appName\",\n      \"operator\": \"IN\"\n    }\n  ]\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/segments")

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\": \"beta-users\",\n  \"constraints\": [\n    {\n      \"contextName\": \"appName\",\n      \"operator\": \"IN\"\n    }\n  ]\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/segments")
  .header("Authorization", "<apiKey>")
  .header("Content-Type", "application/json")
  .body("{\n  \"name\": \"beta-users\",\n  \"constraints\": [\n    {\n      \"contextName\": \"appName\",\n      \"operator\": \"IN\"\n    }\n  ]\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/segments', [
  'body' => '{
  "name": "beta-users",
  "constraints": [
    {
      "contextName": "appName",
      "operator": "IN"
    }
  ]
}',
  '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/segments");
var request = new RestRequest(Method.POST);
request.AddHeader("Authorization", "<apiKey>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"name\": \"beta-users\",\n  \"constraints\": [\n    {\n      \"contextName\": \"appName\",\n      \"operator\": \"IN\"\n    }\n  ]\n}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = [
  "Authorization": "<apiKey>",
  "Content-Type": "application/json"
]
let parameters = [
  "name": "beta-users",
  "constraints": [
    [
      "contextName": "appName",
      "operator": "IN"
    ]
  ]
] as [String : Any]

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

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