Registration#

During registration, Flyte validates the workflow structure and saves the workflow. The registration process also updates the workflow graph.

https://raw.githubusercontent.com/flyteorg/static-resources/main/flyte/concepts/executions/flyte_wf_registration_overview.svg?sanitize=true

Typical Flow#

The following steps elaborate on the specifics of the registration process:

  • Define the tasks using the Flytekit Task Definition language.

  • Define a workflow using the Flytekit Workflow definition language.

  • Use flytectl register CLI to compile the tasks into their serialized representation as described in Flyte Specification language. During this, the task representation is bound to a container that constitutes the code for the task. This associated entity is registered with FlyteAdmin using the registerTask API.

  • Use flytectl register CLI to compile the workflow into their serialized representation as described in Flyte Specification language. The referenced tasks are replaced by their FlyteAdmin registered Identifiers, obtained in the previous step. The associated entity is registered with FlyteAdmin using the registerWorkflow API.

  • Launch an execution using the FlyteAdmin launch execution API, which requires the necessary inputs provided. This is automatically done if the user uses flytectl to launch the execution.

  • Use the FlyteAdmin read APIs to get details of the execution, monitor it to completion, or retrieve a historical execution.

  • OR use the FlyteConsole to visualize the execution in real time as it progresses or visualize any historical execution. The console makes it easy to view debugging information for the execution.

  • Set specific rules such as notification on failure or success or publish all events in the execution to a pub-sub system.

  • Query the datastore to get a summary of all the executions and the compute resources consumed.

Note

Workflows and tasks are purely specifications and can be provided using tools like YAML, JSON, protobuf binary or any other programming language, and hence registration is possible using other tools. Contributions welcome!

Registration in the Backend#

When FlyteAdmin receives a workflow registration request, it uses the workflow compiler to compile and validate the workflow. It also fetches all the referenced tasks and creates a complete workflow closure, which is stored in the metastore. If the workflow compilation fails, the compiler returns an error to the client.