Write Workflows Using Code

You can write workflows in code to create dynamic workflows that can't be predefined. Support for defining workflows in code is part of all the supported SDKs.

Create workflows in code

The workflow in the following examples performs these steps:

1. Get user details: Retrieves the user information based on the userId provided as the workflow input.
2. Determine notification type: Uses a Switch task to check the preferred notification method from the input and determine how to notify the user.
3. Send email: If the notification preference is email, send a message to the user’s email address.
4. Send SMS: If the preference is SMS, send a text message to the phone number.

Select your preferred language and use the code example to define and register the workflow in your Conductor environment.

Java

        ConductorWorkflow<WorkflowInput> workflow = new ConductorWorkflow<>(executor);
        workflow.setName("user_notification");
        workflow.setVersion(1);

        SimpleTask getUserDetails = new SimpleTask("get_user_info", "get_user_info");
        getUserDetails.input("userId", "${workflow.input.userId}");

        SimpleTask sendEmail = new SimpleTask("send_email", "send_email");
        // get user details user info, which contains the email field
        sendEmail.input("email", "${get_user_info.output.email}");

        SimpleTask sendSMS = new SimpleTask("send_sms", "send_sms");
        // get user details user info, which contains the phone Number field
        sendSMS.input("phoneNumber", "${get_user_info.output.phoneNumber}");

        Switch emailOrSMS = new Switch("emailorsms", "${workflow.input.notificationPref}")
                .switchCase(WorkflowInput.NotificationPreference.EMAIL.name(), sendEmail)
                .switchCase(WorkflowInput.NotificationPreference.SMS.name(), sendSMS);

        workflow.add(getUserDetails);
        workflow.add(emailOrSMS);

        //Execute the workflow and get the output
        WorkflowInput input = new WorkflowInput("userA");
        input.setNotificationPref(WorkflowInput.NotificationPreference.EMAIL);
        CompletableFuture<Workflow> workflowExecution = simpleWorkflow.executeDynamic(input);
        Workflow workflowRun = workflowExecution.get(10, TimeUnit.SECONDS);

Python

    workflow = ConductorWorkflow(
        executor=workflow_executor,
        name='user_notification',
        version=1,
    )
    workflow.input_parameters = ['userId', 'notificationPref']
    get_user_info = SimpleTask('get_user_info', 'get_user_info').input('userId', '${workflow.input.userId}')

    decision_task = SwitchTask('emailorsms', '${workflow.input.notificationPref}')
    send_email = SimpleTask('send_email', 'send_email').input('email', '${get_user_info.output.email}')
    send_sms = SimpleTask('send_sms', 'send_sms').input('phoneNumber', '${get_user_info.output.phoneNumber}')

    decision_task.switch_case(NotificationPreference.EMAIL,send_email)
    decision_task.switch_case(NotificationPreference.SMS, send_sms)

    workflow >> get_user_info >> decision_task

    workflow.register(overwrite=True)  # register the workflow with the server

    workflow_run = workflow_executor.workflow_client.execute_workflow(
        body=StartWorkflowRequest(name=workflow.name,version=workflow.version),
        request_id=str(uuid.uuid4()),
        version=workflow.version,
        name=workflow.name,
        wait_until_task_ref='',
        _request_timeout= 60
    )

Go

    getUserInfo := workflow.NewSimpleTask("get_user_info", "get_user_info").
		Input("userId", "${workflow.input.userId}")
	sendEmail := workflow.NewSimpleTask("send_email", "send_email").
		Input("email", "${get_user_info.output.email}")
	sendSMS := workflow.NewSimpleTask("send_sms", "send_sms").
		Input("phoneNumber", "${get_user_info.output.phoneNumber}")

	decision := workflow.NewSwitchTask("email_or_sms", "${workflow.input.notificationPref}").
		SwitchCase(Email, sendEmail).
		SwitchCase(Sms, sendSMS)

	executor.NewWorkflowExecutor(
		api.GetApiClientWithAuthentication(),
	)
	userNotificationWorkflow := workflow.NewConductorWorkflow(workflowExecutor).
		Name("user_notification").
		Version(1).
		InputParameters("userId", "notificationPref").
		Add(getUserInfo).
		Add(decision)

	userNotificationWorkflow.Register(true)

	//Execute workflow synchronously -- and wait for it to complete
	output, err := userNotificationWorkflow.ExecuteWorkflowWithInput(input, "")
	if err != nil {
		fmt.Errorf("error executing workflow %s", err.Error())
		return
	}
	fmt.Printf("Completed executing workflow with id %s and output %s\n", output.WorkflowId, output.Output)

	//Start workflow asynchronously, do not wait for it to complete
	//Get the execution id back which can be used to monitor the workflow execution state
	workflowId, err := userNotificationWorkflow.StartWorkflowWithInput(input)
	if err != nil {
		fmt.Errorf("error executing workflow %s", err.Error())
		return
	}
	fmt.Printf("Started workflow with id %s\n", workflowId)

C#

    @WorkerTask("fraud-check")
    public String checkForFraud(@InputParam("amount") BigDecimal amount, @InputParam("accountId") String accountId) {
        boolean isFraud = fraudService.isFraudulentTxn(accountId, amount);
        if(isFraud) {
            return "This transaction cannot be processed as its flagged for review.";
        }
        return "Deposit of " + amount + " has processed successfully";
    }

JavaScript

const getUserDetailsTask = simpleTask(GET_USER_INFO, GET_USER_INFO, {
    userId: "${workflow.input.userId}",
  });
  const emailOrSmsTask = switchTask("emailorsms", "${workflow.input.notificationPref}", {
    emai: [
      simpleTask(SEND_EMAIL, SEND_EMAIL, {
        email: "${get_user_info.output.email}",
      }),
    ],
    sms:[
      simpleTask(SEND_SMS, SEND_SMS, {
        phoneNumber: "${get_user_info.output.phoneNumber}",
      }),
    ],
  });
  
  const wf = workflow(COMPLEX_WORKFLOW_NAME, [
    getUserDetailsTask,
    emailOrSmsTask,
  ]);
  wf.inputParameters = ['userId', 'notificationPref']
  
  const client = await clientPromise;
  client.metadataResource.create(wf, true);

return wf;

Typescript

const getUserDetailsTask = simpleTask(GET_USER_INFO, GET_USER_INFO, {
    userId: "${workflow.input.userId}",
  });
  const emailOrSmsTask = switchTask(
    "emailorsms",
    "${workflow.input.notificationPref}",
    {
      email: [
        simpleTask(SEND_EMAIL, SEND_EMAIL, {
          email: "${get_user_info.output.email}",
        }),
      ],
      sms: [
        simpleTask(SEND_SMS, SEND_SMS, {
          phoneNumber: "${get_user_info.output.phoneNumber}",
        }),
      ],
    }
  );

  const wf = workflow(COMPLEX_WORKFLOW_NAME, [
    getUserDetailsTask,
    emailOrSmsTask,
  ]);
  wf.inputParameters = ["userId", "notificationPref"];
  
  const client = await clientPromise;
  client.metadataResource.create(wf, true);

return wf;

Clojure

(defn create-tasks
  "Returns workflow tasks"
  []
  (vector (sdk/simple-task (:get-user-info constants) (:get-user-info constants) {:userId "${workflow.input.userId}"})
          (sdk/switch-task "emailorsms" "${workflow.input.notificationPref}" {"email" [(sdk/simple-task (:send-email constants) (:send-email constants) {"email" "${get_user_info.output.email}"})]
                                                                              "sms" [(sdk/simple-task (:send-sms constants) (:send-sms constants) {"phoneNumber" "${get_user_info.output.phoneNumber}"})]} [])))

(defn create-workflow
  "Returns a workflow with tasks"
  [tasks]
  (merge (sdk/workflow (:workflow-name constants) tasks) {:inputParameters ["userId" "notificationPref"]}))