feat(operator): sleep operator

[aglinxinyuan]

Introduce a sleep operator that adds a configurable delay between tuples. This can be useful during the development or testing of the workflow to simulate long-running tasks or processing delays.

It's not visible on the operator panel and will only appear when searched for.

[Copilot]

Pull Request Overview

Introduces a new Sleep operator that pauses processing of each tuple for a configurable duration.

• Adds SleepOpDesc to describe the operator and register it in the logical plan.
• Implements SleepOpExec to apply a blocking delay on each tuple.
• Updates LogicalOp to include SleepOpDesc in the operator registry.

Reviewed Changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated 1 comment.

File	Description
core/workflow-operator/src/main/scala/edu/uci/ics/amber/operator/sleep/SleepOpExec.scala	Implements blocking delay logic in processTuple
core/workflow-operator/src/main/scala/edu/uci/ics/amber/operator/sleep/SleepOpDesc.scala	Defines operator descriptor with JSON schema and exec metadata
core/workflow-operator/src/main/scala/edu/uci/ics/amber/operator/LogicalOp.scala	Registers SleepOpDesc in the global operator registry

Comments suppressed due to low confidence (3)

core/workflow-operator/src/main/scala/edu/uci/ics/amber/operator/sleep/SleepOpDesc.scala:34

• [nitpick] The JSON schema title "n" is vague. Rename it to "time" or "seconds" so it aligns with the time field and improves generated API documentation.

  @JsonSchemaTitle("n")

core/workflow-operator/src/main/scala/edu/uci/ics/amber/operator/sleep/SleepOpDesc.scala:61

• [nitpick] The operator description refers to n seconds, but the parameter is named time. Update the description to mention time (e.g., "Sleep time seconds between each tuple") for consistency.

      "Sleep n seconds between each tuple",

core/workflow-operator/src/main/scala/edu/uci/ics/amber/operator/sleep/SleepOpDesc.scala:31

• There are no tests covering the new Sleep operator. Consider adding unit or integration tests to verify the configured delay and ensure correct operator behavior under various time values.

class SleepOpDesc extends LogicalOp {

[Yicong-Huang]

This operator can be confusing to users. I do not recommend adding it to master. If you really want it, please hide the UI so it can be only searched out, not dragged out.

[aglinxinyuan]

This operator can be confusing to users. I do not recommend adding it to master. If you really want it, please hide the UI so it can be only searched out, not dragged out.

It's now hidden in the operator menu.