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> For a complete documentation index, see https://docs.getunleash.io/api/overwrite-feature-variants-on-environments/llms.txt.
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# Create (overwrite) variants for a feature flag in multiple environments

PUT https://app.unleash-instance.example.com/api/admin/projects/{projectId}/features/{featureName}/variants-batch
Content-Type: application/json

This overwrites the current variants for the feature flag in the :featureName parameter for the :environment parameter.

Reference: https://docs.getunleash.io/api/overwrite-feature-variants-on-environments

## 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

### Path parameters

- `projectId` (string, required)
- `featureName` (string, required)

### Body (application/json)

This endpoint expects a pushVariantsSchema.

- `variants` (list of variantSchema, optional) — The variants to write to the provided environments
- `environments` (list of string, optional) — The enviromnents to write the provided variants to

## Response

### 200

featureVariantsSchema

- `version` (integer, required) — The version of the feature variants schema.
- `variants` (list of variantSchema, required) — All variants defined for a specific feature flag.

## Errors

### 400 Bad Request Error

The request data does not match what we expect.

- `id` (string, optional) — The ID of the error instance
- `name` (string, optional) — The name of the error kind
- `message` (string, optional) — A description of what went wrong.

### 401 Unauthorized Error

Authorization information is missing or invalid. Provide a valid API token as the `authorization` header, e.g. `authorization:*.*.my-admin-token`.

- `id` (string, optional) — The ID of the error instance
- `name` (string, optional) — The name of the error kind
- `message` (string, optional) — A description of what went wrong.

### 403 Forbidden Error

The provided user credentials are valid, but the user does not have the necessary permissions to perform this operation

- `id` (string, optional) — The ID of the error instance
- `name` (string, optional) — The name of the error kind
- `message` (string, optional) — A description of what went wrong.

## Types

### variantSchema

A variant allows for further separation of users into segments. See [our excellent documentation](https://docs.getunleash.io/concepts/feature-flag-variants#what-are-variants) for a more detailed description

- `name` (string, required) — The variants name. Is unique for this feature flag
- `weight` (double, required) — The weight is the likelihood of any one user getting this variant. It is a number between 0 and 1000. See the section on [variant weights](https://docs.getunleash.io/concepts/feature-flag-variants#variant-weight) for more information
- `weightType` (enum, optional) — Set to fix if this variant must have exactly the weight allocated to it. If the type is variable, the weight will adjust so that the total weight of all variants adds up to 1000
  - Allowed values: `variable`, `fix`
- `stickiness` (string, optional) — [Stickiness](https://docs.getunleash.io/concepts/feature-flag-variants#variant-stickiness) is how Unleash guarantees that the same user gets the same variant every time
- `payload` (VariantSchemaPayload, optional) — Extra data configured for this variant
- `overrides` (list of overrideSchema, optional) — Overrides assigning specific variants to specific users. The weighting system automatically assigns users to specific groups for you, but any overrides in this list will take precedence.

### VariantSchemaPayload

Extra data configured for this variant

- `type` (enum, required) — The type of the value. Commonly used types are string, number, json and csv.
  - Allowed values: `json`, `csv`, `string`, `number`
- `value` (string, required) — The actual value of payload

### overrideSchema

An override for deciding which variant should be assigned to a user based on the context name

- `contextName` (string, required) — The name of the context field used to determine overrides
- `values` (list of string, required) — Which values that should be overriden

## Examples

**Request**

```json
{}
```

**Response**

```json
{
  "version": 1,
  "variants": [
    {
      "name": "blue_group",
      "weight": 1.1,
      "weightType": "variable",
      "stickiness": "custom.context.field",
      "payload": {
        "type": "json",
        "value": "{\"color\": \"red\"}"
      },
      "overrides": [
        {
          "contextName": "userId",
          "values": [
            "red",
            "blue"
          ]
        }
      ]
    }
  ]
}
```

**SDK Code**

```python
import requests

url = "https://app.unleash-instance.example.com/api/admin/projects/projectId/features/featureName/variants-batch"

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

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

print(response.json())
```

```javascript
const url = 'https://app.unleash-instance.example.com/api/admin/projects/projectId/features/featureName/variants-batch';
const options = {
  method: 'PUT',
  headers: {Authorization: '<apiKey>', 'Content-Type': 'application/json'},
  body: '{}'
};

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/projects/projectId/features/featureName/variants-batch"

	payload := strings.NewReader("{}")

	req, _ := http.NewRequest("PUT", 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/projects/projectId/features/featureName/variants-batch")

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

request = Net::HTTP::Put.new(url)
request["Authorization"] = '<apiKey>'
request["Content-Type"] = 'application/json'
request.body = "{}"

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.put("https://app.unleash-instance.example.com/api/admin/projects/projectId/features/featureName/variants-batch")
  .header("Authorization", "<apiKey>")
  .header("Content-Type", "application/json")
  .body("{}")
  .asString();
```

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

$client = new \GuzzleHttp\Client();

$response = $client->request('PUT', 'https://app.unleash-instance.example.com/api/admin/projects/projectId/features/featureName/variants-batch', [
  'body' => '{}',
  '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/projects/projectId/features/featureName/variants-batch");
var request = new RestRequest(Method.PUT);
request.AddHeader("Authorization", "<apiKey>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

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

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

let request = NSMutableURLRequest(url: NSURL(string: "https://app.unleash-instance.example.com/api/admin/projects/projectId/features/featureName/variants-batch")! as URL,
                                        cachePolicy: .useProtocolCachePolicy,
                                    timeoutInterval: 10.0)
request.httpMethod = "PUT"
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()
```