This topic describes the FAQ of Serverless workflow.


What is Serverless Workflow?

Serverless workflow is a fully managed cloud service that coordinates distributed tasks. You can orchestrate distributed tasks by defining foreach steps, choice steps, or parallel steps in flows. Serverless workflow coordinates task executions based on the defined steps to track the status transition of each step. When necessary, it executes the user-defined retry logic to ensure the smooth completion of a flow. Serverless workflow provides the logging and auditing features to monitor flow executions, allowing you to diagnose and debug applications.

How does Serverless Workflow work?

You can use Serverless workflow to orchestrate a series of function resources, define both the input and output of each step in a flow, and use built-in control steps to orchestrate complex logic, initiate parallel executions, manage timeout settings, or terminate the flow. In addition, Serverless Workflow provides a graphical interface to visualize the status and sequence of each execution and the real-time status of each step, and provides a detailed record of each execution.

What are the advantages of Serverless Workflow?

  • Service orchestration capabilities: Serverless workflow avoids repeated orchestration, maintains step and execution status, and implements distributed task communication. It also provides visualized flow orchestration and status monitoring tools.
  • Smooth architecture evolution: Serverless workflow can coordinate applications defined in different languages on different infrastructures and networks. Serverless workflow can implement coordination during smooth migration between hybrid clouds, or from a private cloud or Apsara Stack to a hybrid cloud and then to a public cloud, or from a monolithic architecture to a microservices architecture.
  • Fully-managed O&M and pay-as-you-go: Serverless workflow frees maintenance personnel from maintaining the infrastructure and provides secure, highly available, fault-tolerant, and highly durable services. Serverless workflow allows flows at any scale to run at a high concurrency. Concurrency scaling is transparent to users. In addition, users only need to pay the step transition fees.
  • Visual display of application status: Serverless workflow provides a visual interface to display flows and view execution status. This allows business personnel, developers, and O&M personnel to obtain consistent information, reducing communication costs.

How long is the maximum execution time of a flow supported by Serverless Workflow?

Serverless workflow supports a flow execution of up to one year.

How can I execute a flow in Serverless Workflow?

You can run a defined flow in the Serverless Workflow console or run flows by calling API operations or using Serverless Workflow SDK. You can also use Function Compute to execute flows and process data from different event sources.

Which language can be used to compile a flow of Serverless Workflow?

Serverless workflow provides Flow Definition Language (FDL) to help you implement business logic as compiling program code. For more information, see Overview.

Is Serverless Workflow integrated with Cloud Monitor?

Serverless workflow sends flow execution metrics to Cloud Monitor, so you can track the metrics and set alerts by using Cloud Monitor.

Is Serverless Workflow integrated with event sources?

Serverless workflow is not integrated with event sources. The cloud services that are integrated with Serverless Workflow work as event producers. You can call the StartExecution API operation to forward the events generated by event sources to Serverless workflow by using Function Compute. For more information, see Triggers.