curl --request POST \
  --url https://api.onesignal.com/apps/{app_id}/activities/activity/{activity_type} \
  --header 'Authorization: <authorization>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "event": "start",
  "activity_id": "<string>",
  "event_attributes": {},
  "event_updates": {},
  "name": "<string>",
  "contents": {
    "en": "<string>"
  },
  "headings": {
    "en": "<string>"
  },
  "include_aliases": {
    "external_id": [
      "<string>"
    ]
  },
  "include_subscription_ids": [
    "<string>"
  ],
  "included_segments": [
    "<string>"
  ],
  "excluded_segments": [
    "<string>"
  ],
  "filters": [
    {
      "field": "first_session",
      "relation": ">",
      "value": "1",
      "key": "<string>"
    }
  ],
  "stale_date": 123,
  "ios_sound": "<string>",
  "ios_relevance_score": 123,
  "idempotency_key": "<string>"
}
'

import Onesignal from '@onesignal/node-onesignal';

const configuration = Onesignal.createConfiguration({
    restApiKey: 'YOUR_REST_API_KEY',
});
const apiInstance = new Onesignal.DefaultApi(configuration);

// string | Your OneSignal App ID in UUID v4 format.
const appId: string = "YOUR_APP_ID";
// string | The name of the Live Activity defined in your app. This should match the attributes struct used in your app\'s Live Activity implementation.
const activityType: string = "order_status";
// StartLiveActivityRequest
const startLiveActivityRequest: Onesignal.StartLiveActivityRequest = {
    name: "YOUR_NAME",
    event: "start",
    activity_id: "YOUR_ACTIVITY_ID",
    event_attributes: {},
    event_updates: {},
    contents: {},
    headings: {},
  };

try {
  const response = await apiInstance.startLiveActivity(appId, activityType, startLiveActivityRequest);
  console.log(response);
} catch (e) {
  if (e instanceof Onesignal.ApiException) {
    // `e.errorMessages` flattens any error-envelope shape to a `string[]`;
    // the raw parsed body remains on `e.body`.
    console.error("startLiveActivity failed: HTTP " + e.code, e.errorMessages);
  } else {
    throw e;
  }
}

import onesignal
from onesignal.api import default_api
from onesignal.models import *
from pprint import pprint

# See configuration.py for a list of all supported configuration parameters.
# Some of the OneSignal endpoints require ORGANIZATION_API_KEY token for authorization, while others require REST_API_KEY.
# We recommend adding both of them in the configuration page so that you will not need to figure it out yourself.
configuration = onesignal.Configuration(
    rest_api_key = "YOUR_REST_API_KEY", # App REST API key required for most endpoints
    organization_api_key = "YOUR_ORGANIZATION_API_KEY" # Organization key is only required for creating new apps and other top-level endpoints
)


# Enter a context with an instance of the API client
with onesignal.ApiClient(configuration) as api_client:
    # Create an instance of the API class
    api_instance = default_api.DefaultApi(api_client)
    app_id = "YOUR_APP_ID" # Your OneSignal App ID in UUID v4 format. 
    activity_type = "order_status" # The name of the Live Activity defined in your app. This should match the attributes struct used in your app's Live Activity implementation. 
    start_live_activity_request = StartLiveActivityRequest(
        name="YOUR_NAME",
        event="start",
        activity_id="YOUR_ACTIVITY_ID",
        event_attributes={},
        event_updates={},
        contents=LanguageStringMap(),
        headings=LanguageStringMap(),
    ) 

    try:
        # Start Live Activity
        api_response = api_instance.start_live_activity(app_id, activity_type, start_live_activity_request)
        pprint(api_response)
    except onesignal.ApiException as e:
        print("Exception when calling DefaultApi->start_live_activity: %s\n" % e)
        print("Status Code: %s" % e.status)
        print("Response Body: %s" % e.body)

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


// Configure Bearer authorization: rest_api_key
$config = onesignal\client\Configuration::getDefaultConfiguration()
                                                ->setRestApiKeyToken('YOUR_REST_API_KEY')
                                                ->setOrganizationApiKeyToken('YOUR_ORGANIZATION_API_KEY');



$apiInstance = new onesignal\client\Api\DefaultApi(
    // If you want use custom http client, pass your client which implements `GuzzleHttp\ClientInterface`.
    // This is optional, `GuzzleHttp\Client` will be used as default.
    new GuzzleHttp\Client(),
    $config
);
$app_id = 'YOUR_APP_ID'; // string | Your OneSignal App ID in UUID v4 format.
$activity_type = 'order_status'; // string | The name of the Live Activity defined in your app. This should match the attributes struct used in your app's Live Activity implementation.
$start_live_activity_request = new \onesignal\client\model\StartLiveActivityRequest(['name' => 'YOUR_NAME', 'event' => \onesignal\client\model\StartLiveActivityRequest::EVENT_START, 'activity_id' => 'YOUR_ACTIVITY_ID', 'event_attributes' => new \stdClass(), 'event_updates' => new \stdClass(), 'contents' => new \onesignal\client\model\LanguageStringMap(), 'headings' => new \onesignal\client\model\LanguageStringMap()]); // \onesignal\client\model\StartLiveActivityRequest

try {
    $result = $apiInstance->startLiveActivity($app_id, $activity_type, $start_live_activity_request);
    print_r($result);
} catch (\onesignal\client\ApiException $e) {
    echo 'Exception when calling DefaultApi->startLiveActivity: ', $e->getMessage(), PHP_EOL;
    echo 'Status Code: ', $e->getCode(), PHP_EOL;
    // getErrorMessages() flattens any error-envelope shape to a string[];
    // the raw body remains on getResponseBody().
    echo 'Error Messages: ', implode(', ', $e->getErrorMessages()), PHP_EOL;
    echo 'Response Body: ', $e->getResponseBody(), PHP_EOL;
} catch (\Exception $e) {
    echo 'Exception when calling DefaultApi->startLiveActivity: ', $e->getMessage(), PHP_EOL;
}

package main

import (
    "context"
    "fmt"
    "os"

    "github.com/OneSignal/onesignal-go-api/v5"
)

func main() {
    appId := "YOUR_APP_ID" // string | Your OneSignal App ID in UUID v4 format.
    activityType := "order_status" // string | The name of the Live Activity defined in your app. This should match the attributes struct used in your app's Live Activity implementation.
    startLiveActivityRequest := *onesignal.NewStartLiveActivityRequest("YOUR_NAME", "start", "YOUR_ACTIVITY_ID", map[string]interface{}{"key": "value"}, map[string]interface{}{"key": "value"}, *onesignal.NewLanguageStringMap(), *onesignal.NewLanguageStringMap()) // StartLiveActivityRequest | 

    configuration := onesignal.NewConfiguration()
    apiClient := onesignal.NewAPIClient(configuration)

    restAuth := context.WithValue(context.Background(), onesignal.RestApiKey, "YOUR_REST_API_KEY") // App REST API key required for most endpoints

    resp, r, err := apiClient.DefaultApi.StartLiveActivity(restAuth, appId, activityType).StartLiveActivityRequest(startLiveActivityRequest).Execute()

    if err != nil {
        fmt.Fprintf(os.Stderr, "Error when calling `DefaultApi.StartLiveActivity``: %v\n", err)
        fmt.Fprintf(os.Stderr, "Full HTTP response: %v\n", r)
        if apiErr, ok := err.(*onesignal.GenericOpenAPIError); ok {
            // ErrorMessages() flattens any error-envelope shape to a []string;
            // the raw body remains on Body().
            fmt.Fprintf(os.Stderr, "Error Messages: %v\n", apiErr.ErrorMessages())
            fmt.Fprintf(os.Stderr, "Response Body: %s\n", apiErr.Body())
        }
    }
    // response from `StartLiveActivity`: StartLiveActivitySuccessResponse
    fmt.Fprintf(os.Stdout, "Response from `DefaultApi.StartLiveActivity`: %v\n", resp)
}

require 'onesignal'
# setup authorization
OneSignal.configure do |config|
  # Configure Bearer authorization: rest_api_key
  config.rest_api_key = 'YOUR_REST_API_KEY'

end

api_instance = OneSignal::DefaultApi.new
app_id = 'YOUR_APP_ID' # String | Your OneSignal App ID in UUID v4 format.
activity_type = 'order_status' # String | The name of the Live Activity defined in your app. This should match the attributes struct used in your app's Live Activity implementation.
start_live_activity_request = OneSignal::StartLiveActivityRequest.new({name: 'YOUR_NAME', event: 'start', activity_id: 'YOUR_ACTIVITY_ID', event_attributes: {}, event_updates: {}, contents: OneSignal::LanguageStringMap.new, headings: OneSignal::LanguageStringMap.new}) # StartLiveActivityRequest | 

begin
  # Start Live Activity
  result = api_instance.start_live_activity(app_id, activity_type, start_live_activity_request)
  p result
rescue OneSignal::ApiError => e
  puts "Error when calling DefaultApi->start_live_activity: #{e}"
  puts "Status Code: #{e.code}"
  # `e.error_messages` flattens any error-envelope shape to an Array<String>;
  # the raw body remains on `e.response_body`.
  puts "Error Messages: #{e.error_messages}"
  puts "Response Body: #{e.response_body}"
end

// Import classes:
import java.util.Arrays;
import java.util.List;
import com.onesignal.client.ApiClient;
import com.onesignal.client.ApiException;
import com.onesignal.client.Configuration;
import com.onesignal.client.auth.*;
import com.onesignal.client.model.*;
import com.onesignal.client.api.DefaultApi;

public class Example {
  public static void main(String[] args) {
    ApiClient defaultClient = Configuration.getDefaultApiClient();
    defaultClient.setBasePath("https://api.onesignal.com");
    
    // Configure HTTP bearer authorization: rest_api_key
    HttpBearerAuth rest_api_key = (HttpBearerAuth) defaultClient.getAuthentication("rest_api_key");
    rest_api_key.setBearerToken("YOUR_REST_API_KEY");

    DefaultApi apiInstance = new DefaultApi(defaultClient);
    String appId = "YOUR_APP_ID"; // String | Your OneSignal App ID in UUID v4 format.
    String activityType = "order_status"; // String | The name of the Live Activity defined in your app. This should match the attributes struct used in your app's Live Activity implementation.
    StartLiveActivityRequest startLiveActivityRequest = new StartLiveActivityRequest().name("YOUR_NAME").event(StartLiveActivityRequest.EventEnum.START).activityId("YOUR_ACTIVITY_ID").eventAttributes(new Object()).eventUpdates(new Object()).contents(new LanguageStringMap()).headings(new LanguageStringMap()); // StartLiveActivityRequest | 
    try {
      StartLiveActivitySuccessResponse result = apiInstance.startLiveActivity(appId, activityType, startLiveActivityRequest);
      System.out.println(result);
    } catch (ApiException e) {
      System.err.println("Exception when calling DefaultApi#startLiveActivity");
      System.err.println("Status code: " + e.getCode());
      // getErrorMessages() flattens any error-envelope shape to a List<String>;
      // the raw body remains on getResponseBody().
      System.err.println("Error messages: " + e.getErrorMessages());
      System.err.println("Reason: " + e.getResponseBody());
      System.err.println("Response headers: " + e.getResponseHeaders());
      e.printStackTrace();
    }
  }
}

using System;
using System.Collections.Generic;
using System.Diagnostics;
using OneSignalApi.Api;
using OneSignalApi.Client;
using OneSignalApi.Model;

namespace Example
{
    public class StartLiveActivityExample
    {
        public static void Main()
        {
            Configuration config = new Configuration();
            config.BasePath = "https://api.onesignal.com";
            // Configure Bearer token for authorization: rest_api_key
            config.AccessToken = "YOUR_REST_API_KEY";

            var apiInstance = new DefaultApi(config);
            var appId = "YOUR_APP_ID";  // string | Your OneSignal App ID in UUID v4 format.
            var activityType = "order_status";  // string | The name of the Live Activity defined in your app. This should match the attributes struct used in your app's Live Activity implementation.
            var startLiveActivityRequest = new StartLiveActivityRequest(name: "YOUR_NAME", _event: StartLiveActivityRequest.EventEnum.Start, activityId: "YOUR_ACTIVITY_ID", eventAttributes: new Object(), eventUpdates: new Object(), contents: new LanguageStringMap(), headings: new LanguageStringMap()); // StartLiveActivityRequest | 

            try
            {
                // Start Live Activity
                StartLiveActivitySuccessResponse result = apiInstance.StartLiveActivity(appId, activityType, startLiveActivityRequest);
                Debug.WriteLine(result);
            }
            catch (ApiException  e)
            {
                Debug.Print("Exception when calling DefaultApi.StartLiveActivity: " + e.Message );
                Debug.Print("Status Code: "+ e.ErrorCode);
                // e.ErrorMessages flattens any error-envelope shape to an IReadOnlyList<string>;
                // the raw body remains on e.ErrorContent.
                Debug.Print("Error Messages: " + string.Join(", ", e.ErrorMessages));
                Debug.Print("Response Body: " + e.ErrorContent);
                Debug.Print(e.StackTrace);
            }
        }
    }
}

use onesignal_rust_api::apis::configuration::Configuration;
use onesignal_rust_api::apis::default_api;

use onesignal_rust_api::models;


#[tokio::main]
async fn main() {
    let mut configuration = Configuration::new();
    configuration.rest_api_key_token = Some("YOUR_REST_API_KEY".to_string());


    // Realistic values are pulled from the spec's `example:` fields where present.
    let app_id: &str = "YOUR_APP_ID";
    let activity_type: &str = "order_status";
    let start_live_activity_request: models::StartLiveActivityRequest = models::StartLiveActivityRequest::new("YOUR_NAME".to_string(), models::start_live_activity_request::EventType::Start, "YOUR_ACTIVITY_ID".to_string(), serde_json::json!({}), serde_json::json!({}), models::LanguageStringMap::new(), models::LanguageStringMap::new());

    match default_api::start_live_activity(&configuration, app_id, activity_type, start_live_activity_request).await {
        Ok(resp) => println!("{:?}", resp),
        Err(e @ onesignal_rust_api::apis::Error::ResponseError(_)) => {
            // `e.error_messages()` flattens any error-envelope shape to a Vec<String>;
            // the raw response remains on the ResponseError variant.
            eprintln!("start_live_activity failed: {:?}", e.error_messages());
        }
        Err(e) => eprintln!("start_live_activity failed: {:?}", e),
    }
}

{
  "notification_id": "<string>"
}

{
  "errors": [
    "Reason for the message not being started. Usually due to the activity type not being found in the app."
  ]
}

{
  "errors": [
    "API rate limit exceeded"
  ]
}

{
  "errors": [
    "Service temporarily unavailable"
  ]
}