

There are more AWS SDK examples available in the [AWS Doc SDK Examples](https://github.com/awsdocs/aws-doc-sdk-examples) GitHub repo.

# Step Functions examples using SDK for Kotlin
<a name="kotlin_1_sfn_code_examples"></a>

The following code examples show you how to perform actions and implement common scenarios by using the AWS SDK for Kotlin with Step Functions.

*Basics* are code examples that show you how to perform the essential operations within a service.

*Actions* are code excerpts from larger programs and must be run in context. While actions show you how to call individual service functions, you can see actions in context in their related scenarios.

Each example includes a link to the complete source code, where you can find instructions on how to set up and run the code in context.

**Topics**
+ [Get started](#get_started)
+ [Basics](#basics)
+ [Actions](#actions)

## Get started
<a name="get_started"></a>

### Hello Step Functions
<a name="sfn_Hello_kotlin_1_topic"></a>

The following code example shows how to get started using Step Functions.

**SDK for Kotlin**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/kotlin/services/stepfunctions#code-examples). 

```
import aws.sdk.kotlin.services.sfn.SfnClient
import aws.sdk.kotlin.services.sfn.model.ListStateMachinesRequest

/**
 Before running this Kotlin code example, set up your development environment,
 including your credentials.

 For more information, see the following documentation topic:
 https://docs.aws.amazon.com/sdk-for-kotlin/latest/developer-guide/setup.html
 */

suspend fun main() {
    println(DASHES)
    println("Welcome to the AWS Step Functions Hello example.")
    println("Lets list up to ten of your state machines:")
    println(DASHES)

    listMachines()
}

suspend fun listMachines() {
    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        val response = sfnClient.listStateMachines(ListStateMachinesRequest {})
        response.stateMachines?.forEach { machine ->
            println("The name of the state machine is ${machine.name}")
            println("The ARN value is ${machine.stateMachineArn}")
        }
    }
}
```
+  For API details, see [ListStateMachines](https://sdk.amazonaws.com/kotlin/api/latest/index.html) in *AWS SDK for Kotlin API reference*. 

## Basics
<a name="basics"></a>

### Learn the basics
<a name="sfn_Scenario_GetStartedStateMachines_kotlin_1_topic"></a>

The following code example shows how to:
+ Create an activity.
+ Create a state machine from an Amazon States Language definition that contains the previously created activity as a step.
+ Run the state machine and respond to the activity with user input.
+ Get the final status and output after the run completes, then clean up resources.

**SDK for Kotlin**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/kotlin/services/stepfunctions#code-examples). 

```
import aws.sdk.kotlin.services.iam.IamClient
import aws.sdk.kotlin.services.iam.model.CreateRoleRequest
import aws.sdk.kotlin.services.sfn.SfnClient
import aws.sdk.kotlin.services.sfn.model.CreateActivityRequest
import aws.sdk.kotlin.services.sfn.model.CreateStateMachineRequest
import aws.sdk.kotlin.services.sfn.model.DeleteActivityRequest
import aws.sdk.kotlin.services.sfn.model.DeleteStateMachineRequest
import aws.sdk.kotlin.services.sfn.model.DescribeExecutionRequest
import aws.sdk.kotlin.services.sfn.model.DescribeStateMachineRequest
import aws.sdk.kotlin.services.sfn.model.GetActivityTaskRequest
import aws.sdk.kotlin.services.sfn.model.ListActivitiesRequest
import aws.sdk.kotlin.services.sfn.model.ListStateMachinesRequest
import aws.sdk.kotlin.services.sfn.model.SendTaskSuccessRequest
import aws.sdk.kotlin.services.sfn.model.StartExecutionRequest
import aws.sdk.kotlin.services.sfn.model.StateMachineType
import aws.sdk.kotlin.services.sfn.paginators.listActivitiesPaginated
import aws.sdk.kotlin.services.sfn.paginators.listStateMachinesPaginated
import com.fasterxml.jackson.databind.JsonNode
import com.fasterxml.jackson.databind.ObjectMapper
import com.fasterxml.jackson.databind.node.ObjectNode
import kotlinx.coroutines.flow.transform
import java.util.Scanner
import java.util.UUID
import kotlin.collections.ArrayList
import kotlin.system.exitProcess

/**
 To run this code example, place the chat_sfn_state_machine.json file into your project's resources folder.

 You can obtain the JSON file to create a state machine in the following GitHub location:

 https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/resources/sample_files

 Before running this Kotlin code example, set up your development environment,
 including your credentials.

 For more information, see the following documentation topic:
 https://docs.aws.amazon.com/sdk-for-kotlin/latest/developer-guide/setup.html

 This Kotlin code example performs the following tasks:

 1. List activities using a paginator.
 2. List state machines using a paginator.
 3. Creates an activity.
 4. Creates a state machine.
 5. Describes the state machine.
 6. Starts execution of the state machine and interacts with it.
 7. Describes the execution.
 8. Deletes the activity.
 9. Deletes the state machine.
 */

val DASHES: String = String(CharArray(80)).replace("\u0000", "-")

suspend fun main(args: Array<String>) {
    val usage = """
    Usage:
        <roleARN> <activityName> <stateMachineName>

    Where:
        roleName - The name of the IAM role to create for this state machine.
        activityName - The name of an activity to create.    
        stateMachineName - The name of the state machine to create.
        jsonFile - The location of the chat_sfn_state_machine.json file. You can located it in resources/sample_files. 
    """

    if (args.size != 4) {
        println(usage)
        exitProcess(0)
    }

    val roleName = args[0]
    val activityName = args[1]
    val stateMachineName = args[2]
    val jsonFile = args[3]
    val sc = Scanner(System.`in`)
    var action = false

    val polJSON = """{
    "Version":"2012-10-17",		 	 	 
    "Statement": [
        {
            "Sid": "",
            "Effect": "Allow",
            "Principal": {
                "Service": "states.amazonaws.com"
            },
            "Action": "sts:AssumeRole"
        }
    ]
    }"""

    println(DASHES)
    println("Welcome to the AWS Step Functions example scenario.")
    println(DASHES)

    println(DASHES)
    println("1. List activities using a Paginator.")
    listActivitesPagnator()
    println(DASHES)

    println(DASHES)
    println("2. List state machines using a paginator.")
    listStatemachinesPagnator()
    println(DASHES)

    println(DASHES)
    println("3. Create a new activity.")
    val activityArn = createActivity(activityName)
    println("The ARN of the Activity is $activityArn")
    println(DASHES)

    // Get JSON to use for the state machine and place the activityArn value into it.
    val stream = GetStream()
    val jsonString = stream.getStream(jsonFile)

    // Modify the Resource node.
    val objectMapper = ObjectMapper()
    val root: JsonNode = objectMapper.readTree(jsonString)
    (root.path("States").path("GetInput") as ObjectNode).put("Resource", activityArn)

    // Convert the modified Java object back to a JSON string.
    val stateDefinition = objectMapper.writeValueAsString(root)
    println(stateDefinition)

    println(DASHES)
    println("4. Create a state machine.")
    val roleARN = createIAMRole(roleName, polJSON)
    val stateMachineArn = createMachine(roleARN, stateMachineName, stateDefinition)
    println("The ARN of the state machine is $stateMachineArn")
    println(DASHES)

    println(DASHES)
    println("5. Describe the state machine.")
    describeStateMachine(stateMachineArn)
    println("What should ChatSFN call you?")
    val userName = sc.nextLine()
    println("Hello $userName")
    println(DASHES)

    println(DASHES)
    // The JSON to pass to the StartExecution call.
    val executionJson = "{ \"name\" : \"$userName\" }"
    println(executionJson)
    println("6. Start execution of the state machine and interact with it.")
    val runArn = startWorkflow(stateMachineArn, executionJson)
    println("The ARN of the state machine execution is $runArn")
    var myList: List<String>
    while (!action) {
        myList = getActivityTask(activityArn)
        println("ChatSFN: " + myList[1])
        println("$userName please specify a value.")
        val myAction = sc.nextLine()
        if (myAction.compareTo("done") == 0) {
            action = true
        }
        println("You have selected $myAction")
        val taskJson = "{ \"action\" : \"$myAction\" }"
        println(taskJson)
        sendTaskSuccess(myList[0], taskJson)
    }
    println(DASHES)

    println(DASHES)
    println("7. Describe the execution.")
    describeExe(runArn)
    println(DASHES)

    println(DASHES)
    println("8. Delete the activity.")
    deleteActivity(activityArn)
    println(DASHES)

    println(DASHES)
    println("9. Delete the state machines.")
    deleteMachine(stateMachineArn)
    println(DASHES)

    println(DASHES)
    println("The AWS Step Functions example scenario is complete.")
    println(DASHES)
}

suspend fun listStatemachinesPagnator() {
    val machineRequest =
        ListStateMachinesRequest {
            maxResults = 10
        }

    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        sfnClient
            .listStateMachinesPaginated(machineRequest)
            .transform { it.stateMachines?.forEach { obj -> emit(obj) } }
            .collect { obj ->
                println(" The state machine ARN is ${obj.stateMachineArn}")
            }
    }
}

suspend fun listActivitesPagnator() {
    val activitiesRequest =
        ListActivitiesRequest {
            maxResults = 10
        }

    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        sfnClient
            .listActivitiesPaginated(activitiesRequest)
            .transform { it.activities?.forEach { obj -> emit(obj) } }
            .collect { obj ->
                println(" The activity ARN is ${obj.activityArn}")
            }
    }
}

suspend fun deleteMachine(stateMachineArnVal: String?) {
    val deleteStateMachineRequest =
        DeleteStateMachineRequest {
            stateMachineArn = stateMachineArnVal
        }

    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        sfnClient.deleteStateMachine(deleteStateMachineRequest)
        println("$stateMachineArnVal was successfully deleted.")
    }
}

suspend fun deleteActivity(actArn: String?) {
    val activityRequest =
        DeleteActivityRequest {
            activityArn = actArn
        }

    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        sfnClient.deleteActivity(activityRequest)
        println("You have deleted $actArn")
    }
}

suspend fun describeExe(executionArnVal: String?) {
    val executionRequest =
        DescribeExecutionRequest {
            executionArn = executionArnVal
        }

    var status = ""
    var hasSucceeded = false
    while (!hasSucceeded) {
        SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
            val response = sfnClient.describeExecution(executionRequest)
            status = response.status.toString()
            if (status.compareTo("Running") == 0) {
                println("The state machine is still running, let's wait for it to finish.")
                Thread.sleep(2000)
            } else if (status.compareTo("Succeeded") == 0) {
                println("The Step Function workflow has succeeded")
                hasSucceeded = true
            } else {
                println("The Status is $status")
            }
        }
    }
    println("The Status is $status")
}

suspend fun sendTaskSuccess(
    token: String?,
    json: String?,
) {
    val successRequest =
        SendTaskSuccessRequest {
            taskToken = token
            output = json
        }
    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        sfnClient.sendTaskSuccess(successRequest)
    }
}

suspend fun getActivityTask(actArn: String?): List<String> {
    val myList: MutableList<String> = ArrayList()
    val getActivityTaskRequest =
        GetActivityTaskRequest {
            activityArn = actArn
        }
    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        val response = sfnClient.getActivityTask(getActivityTaskRequest)
        myList.add(response.taskToken.toString())
        myList.add(response.input.toString())
        return myList
    }
}

suspend fun startWorkflow(
    stateMachineArnVal: String?,
    jsonEx: String?,
): String? {
    val uuid = UUID.randomUUID()
    val uuidValue = uuid.toString()
    val executionRequest =
        StartExecutionRequest {
            input = jsonEx
            stateMachineArn = stateMachineArnVal
            name = uuidValue
        }
    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        val response = sfnClient.startExecution(executionRequest)
        return response.executionArn
    }
}

suspend fun describeStateMachine(stateMachineArnVal: String?) {
    val stateMachineRequest =
        DescribeStateMachineRequest {
            stateMachineArn = stateMachineArnVal
        }
    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        val response = sfnClient.describeStateMachine(stateMachineRequest)
        println("The name of the State machine is ${response.name}")
        println("The status of the State machine is ${response.status}")
        println("The ARN value of the State machine is ${response.stateMachineArn}")
        println("The role ARN value is ${response.roleArn}")
    }
}

suspend fun createMachine(
    roleARNVal: String?,
    stateMachineName: String?,
    jsonVal: String?,
): String? {
    val machineRequest =
        CreateStateMachineRequest {
            definition = jsonVal
            name = stateMachineName
            roleArn = roleARNVal
            type = StateMachineType.Standard
        }

    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        val response = sfnClient.createStateMachine(machineRequest)
        return response.stateMachineArn
    }
}

suspend fun createIAMRole(
    roleNameVal: String?,
    polJSON: String?,
): String? {
    val request =
        CreateRoleRequest {
            roleName = roleNameVal
            assumeRolePolicyDocument = polJSON
            description = "Created using the AWS SDK for Kotlin"
        }

    IamClient.fromEnvironment { region = "AWS_GLOBAL" }.use { iamClient ->
        val response = iamClient.createRole(request)
        return response.role?.arn
    }
}

suspend fun createActivity(activityName: String): String? {
    val activityRequest =
        CreateActivityRequest {
            name = activityName
        }

    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        val response = sfnClient.createActivity(activityRequest)
        return response.activityArn
    }
}
```
+ For API details, see the following topics in *AWS SDK for Kotlin API reference*.
  + [CreateActivity](https://sdk.amazonaws.com/kotlin/api/latest/index.html)
  + [CreateStateMachine](https://sdk.amazonaws.com/kotlin/api/latest/index.html)
  + [DeleteActivity](https://sdk.amazonaws.com/kotlin/api/latest/index.html)
  + [DeleteStateMachine](https://sdk.amazonaws.com/kotlin/api/latest/index.html)
  + [DescribeExecution](https://sdk.amazonaws.com/kotlin/api/latest/index.html)
  + [DescribeStateMachine](https://sdk.amazonaws.com/kotlin/api/latest/index.html)
  + [GetActivityTask](https://sdk.amazonaws.com/kotlin/api/latest/index.html)
  + [ListActivities](https://sdk.amazonaws.com/kotlin/api/latest/index.html)
  + [ListStateMachines](https://sdk.amazonaws.com/kotlin/api/latest/index.html)
  + [SendTaskSuccess](https://sdk.amazonaws.com/kotlin/api/latest/index.html)
  + [StartExecution](https://sdk.amazonaws.com/kotlin/api/latest/index.html)
  + [StopExecution](https://sdk.amazonaws.com/kotlin/api/latest/index.html)

## Actions
<a name="actions"></a>

### `CreateActivity`
<a name="sfn_CreateActivity_kotlin_1_topic"></a>

The following code example shows how to use `CreateActivity`.

**SDK for Kotlin**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/kotlin/services/stepfunctions#code-examples). 

```
suspend fun createActivity(activityName: String): String? {
    val activityRequest =
        CreateActivityRequest {
            name = activityName
        }

    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        val response = sfnClient.createActivity(activityRequest)
        return response.activityArn
    }
}
```
+  For API details, see [CreateActivity](https://sdk.amazonaws.com/kotlin/api/latest/index.html) in *AWS SDK for Kotlin API reference*. 

### `CreateStateMachine`
<a name="sfn_CreateStateMachine_kotlin_1_topic"></a>

The following code example shows how to use `CreateStateMachine`.

**SDK for Kotlin**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/kotlin/services/stepfunctions#code-examples). 

```
suspend fun createMachine(
    roleARNVal: String?,
    stateMachineName: String?,
    jsonVal: String?,
): String? {
    val machineRequest =
        CreateStateMachineRequest {
            definition = jsonVal
            name = stateMachineName
            roleArn = roleARNVal
            type = StateMachineType.Standard
        }

    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        val response = sfnClient.createStateMachine(machineRequest)
        return response.stateMachineArn
    }
}
```
+  For API details, see [CreateStateMachine](https://sdk.amazonaws.com/kotlin/api/latest/index.html) in *AWS SDK for Kotlin API reference*. 

### `DeleteActivity`
<a name="sfn_DeleteActivity_kotlin_1_topic"></a>

The following code example shows how to use `DeleteActivity`.

**SDK for Kotlin**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/kotlin/services/stepfunctions#code-examples). 

```
suspend fun deleteActivity(actArn: String?) {
    val activityRequest =
        DeleteActivityRequest {
            activityArn = actArn
        }

    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        sfnClient.deleteActivity(activityRequest)
        println("You have deleted $actArn")
    }
}
```
+  For API details, see [DeleteActivity](https://sdk.amazonaws.com/kotlin/api/latest/index.html) in *AWS SDK for Kotlin API reference*. 

### `DeleteStateMachine`
<a name="sfn_DeleteStateMachine_kotlin_1_topic"></a>

The following code example shows how to use `DeleteStateMachine`.

**SDK for Kotlin**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/kotlin/services/stepfunctions#code-examples). 

```
suspend fun deleteMachine(stateMachineArnVal: String?) {
    val deleteStateMachineRequest =
        DeleteStateMachineRequest {
            stateMachineArn = stateMachineArnVal
        }

    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        sfnClient.deleteStateMachine(deleteStateMachineRequest)
        println("$stateMachineArnVal was successfully deleted.")
    }
}
```
+  For API details, see [DeleteStateMachine](https://sdk.amazonaws.com/kotlin/api/latest/index.html) in *AWS SDK for Kotlin API reference*. 

### `DescribeExecution`
<a name="sfn_DescribeExecution_kotlin_1_topic"></a>

The following code example shows how to use `DescribeExecution`.

**SDK for Kotlin**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/kotlin/services/stepfunctions#code-examples). 

```
suspend fun describeExe(executionArnVal: String?) {
    val executionRequest =
        DescribeExecutionRequest {
            executionArn = executionArnVal
        }

    var status = ""
    var hasSucceeded = false
    while (!hasSucceeded) {
        SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
            val response = sfnClient.describeExecution(executionRequest)
            status = response.status.toString()
            if (status.compareTo("Running") == 0) {
                println("The state machine is still running, let's wait for it to finish.")
                Thread.sleep(2000)
            } else if (status.compareTo("Succeeded") == 0) {
                println("The Step Function workflow has succeeded")
                hasSucceeded = true
            } else {
                println("The Status is $status")
            }
        }
    }
    println("The Status is $status")
}
```
+  For API details, see [DescribeExecution](https://sdk.amazonaws.com/kotlin/api/latest/index.html) in *AWS SDK for Kotlin API reference*. 

### `DescribeStateMachine`
<a name="sfn_DescribeStateMachine_kotlin_1_topic"></a>

The following code example shows how to use `DescribeStateMachine`.

**SDK for Kotlin**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/kotlin/services/stepfunctions#code-examples). 

```
suspend fun describeStateMachine(stateMachineArnVal: String?) {
    val stateMachineRequest =
        DescribeStateMachineRequest {
            stateMachineArn = stateMachineArnVal
        }
    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        val response = sfnClient.describeStateMachine(stateMachineRequest)
        println("The name of the State machine is ${response.name}")
        println("The status of the State machine is ${response.status}")
        println("The ARN value of the State machine is ${response.stateMachineArn}")
        println("The role ARN value is ${response.roleArn}")
    }
}
```
+  For API details, see [DescribeStateMachine](https://sdk.amazonaws.com/kotlin/api/latest/index.html) in *AWS SDK for Kotlin API reference*. 

### `GetActivityTask`
<a name="sfn_GetActivityTask_kotlin_1_topic"></a>

The following code example shows how to use `GetActivityTask`.

**SDK for Kotlin**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/kotlin/services/stepfunctions#code-examples). 

```
suspend fun getActivityTask(actArn: String?): List<String> {
    val myList: MutableList<String> = ArrayList()
    val getActivityTaskRequest =
        GetActivityTaskRequest {
            activityArn = actArn
        }
    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        val response = sfnClient.getActivityTask(getActivityTaskRequest)
        myList.add(response.taskToken.toString())
        myList.add(response.input.toString())
        return myList
    }
}
```
+  For API details, see [GetActivityTask](https://sdk.amazonaws.com/kotlin/api/latest/index.html) in *AWS SDK for Kotlin API reference*. 

### `ListActivities`
<a name="sfn_ListActivities_kotlin_1_topic"></a>

The following code example shows how to use `ListActivities`.

**SDK for Kotlin**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/kotlin/services/stepfunctions#code-examples). 

```
suspend fun listAllActivites() {
    val activitiesRequest =
        ListActivitiesRequest {
            maxResults = 10
        }

    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        val response = sfnClient.listActivities(activitiesRequest)
        response.activities?.forEach { item ->
            println("The activity ARN is ${item.activityArn}")
            println("The activity name is ${item.name}")
        }
    }
}
```
+  For API details, see [ListActivities](https://sdk.amazonaws.com/kotlin/api/latest/index.html) in *AWS SDK for Kotlin API reference*. 

### `ListExecutions`
<a name="sfn_ListExecutions_kotlin_1_topic"></a>

The following code example shows how to use `ListExecutions`.

**SDK for Kotlin**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/kotlin/services/stepfunctions#code-examples). 

```
suspend fun getExeHistory(exeARN: String?) {
    val historyRequest =
        GetExecutionHistoryRequest {
            executionArn = exeARN
            maxResults = 10
        }

    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        val response = sfnClient.getExecutionHistory(historyRequest)
        response.events?.forEach { event ->
            println("The event type is ${event.type}")
        }
    }
}
```
+  For API details, see [ListExecutions](https://sdk.amazonaws.com/kotlin/api/latest/index.html) in *AWS SDK for Kotlin API reference*. 

### `ListStateMachines`
<a name="sfn_ListStateMachines_kotlin_1_topic"></a>

The following code example shows how to use `ListStateMachines`.

**SDK for Kotlin**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/kotlin/services/stepfunctions#code-examples). 

```
import aws.sdk.kotlin.services.sfn.SfnClient
import aws.sdk.kotlin.services.sfn.model.ListStateMachinesRequest

/**
 Before running this Kotlin code example, set up your development environment,
 including your credentials.

 For more information, see the following documentation topic:
 https://docs.aws.amazon.com/sdk-for-kotlin/latest/developer-guide/setup.html
 */

suspend fun main() {
    println(DASHES)
    println("Welcome to the AWS Step Functions Hello example.")
    println("Lets list up to ten of your state machines:")
    println(DASHES)

    listMachines()
}

suspend fun listMachines() {
    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        val response = sfnClient.listStateMachines(ListStateMachinesRequest {})
        response.stateMachines?.forEach { machine ->
            println("The name of the state machine is ${machine.name}")
            println("The ARN value is ${machine.stateMachineArn}")
        }
    }
}
```
+  For API details, see [ListStateMachines](https://sdk.amazonaws.com/kotlin/api/latest/index.html) in *AWS SDK for Kotlin API reference*. 

### `SendTaskSuccess`
<a name="sfn_SendTaskSuccess_kotlin_1_topic"></a>

The following code example shows how to use `SendTaskSuccess`.

**SDK for Kotlin**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/kotlin/services/stepfunctions#code-examples). 

```
suspend fun sendTaskSuccess(
    token: String?,
    json: String?,
) {
    val successRequest =
        SendTaskSuccessRequest {
            taskToken = token
            output = json
        }
    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        sfnClient.sendTaskSuccess(successRequest)
    }
}
```
+  For API details, see [SendTaskSuccess](https://sdk.amazonaws.com/kotlin/api/latest/index.html) in *AWS SDK for Kotlin API reference*. 

### `StartExecution`
<a name="sfn_StartExecution_kotlin_1_topic"></a>

The following code example shows how to use `StartExecution`.

**SDK for Kotlin**  
 There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/kotlin/services/stepfunctions#code-examples). 

```
suspend fun startWorkflow(
    stateMachineArnVal: String?,
    jsonEx: String?,
): String? {
    val uuid = UUID.randomUUID()
    val uuidValue = uuid.toString()
    val executionRequest =
        StartExecutionRequest {
            input = jsonEx
            stateMachineArn = stateMachineArnVal
            name = uuidValue
        }
    SfnClient.fromEnvironment { region = "us-east-1" }.use { sfnClient ->
        val response = sfnClient.startExecution(executionRequest)
        return response.executionArn
    }
}
```
+  For API details, see [StartExecution](https://sdk.amazonaws.com/kotlin/api/latest/index.html) in *AWS SDK for Kotlin API reference*. 