Add durable-timer sleep step to DSL workflow

README.md

@@ -168,6 +168,7 @@ Each step can have the following fields:
 - `c`: (array of steps, optional) Child steps to execute as a child workflow
 - `r`: (int, optional) Number of times to repeat this step (default 1)
 - `p`: (int, optional) Size in bytes of padding data to add to activity inputs for increasing history size
+- `t`: (int, optional) Seconds to sleep via a durable timer (`workflow.Sleep`) instead of the `Sleep` activity. A value of 0 (the default) is a no-op.
 
 #### Examples
 
@@ -194,6 +195,16 @@ This example demonstrates using padding to increase history size by adding paddi
 ]
 ```
 
+This example sleeps for 1 second using a durable timer (`workflow.Sleep`, no activity), runs `Echo`, then sleeps 5 seconds:
+
+```
+[
+  {"t": 1},
+  {"a": "Echo", "i": {"Message": "test"}},
+  {"t": 5}
+]
+```
+
 You can start this workflow using `tctl` or any Temporal client, for example:
 
 ```

workflows/workflow.go

@@ -17,13 +17,15 @@ type ReceiveSignalWorkflowInput struct {
 	Name  string
 }
 
-// DSL step: either an activity or a child workflow (which is always this workflow)
+// DSL step: an activity, a child workflow (which is always this workflow),
+// and/or a user timer.
 type DSLStep struct {
-	Activity    string      `json:"a,omitempty"`
-	Input       interface{} `json:"i,omitempty"`
-	Child       []DSLStep   `json:"c,omitempty"`
-	Repeat      int         `json:"r,omitempty"`
-	PaddingSize int         `json:"p,omitempty"` // Size in bytes of padding to add to activity inputs
+	Activity     string      `json:"a,omitempty"`
+	Input        interface{} `json:"i,omitempty"`
+	Child        []DSLStep   `json:"c,omitempty"`
+	Repeat       int         `json:"r,omitempty"`
+	PaddingSize  int         `json:"p,omitempty"` // Size in bytes of padding to add to activity inputs
+	SleepSeconds int         `json:"t,omitempty"` // Seconds to sleep using workflow.Sleep
 }
 
 // injectPadding adds padding data to an activity input by adding a Padding field
@@ -85,6 +87,11 @@ func DSLWorkflow(ctx workflow.Context, steps []DSLStep) error {
 			repeat = 1
 		}
 		for i := 0; i < repeat; i++ {
+			if step.SleepSeconds > 0 {
+				if err := workflow.Sleep(ctx, time.Duration(step.SleepSeconds)*time.Second); err != nil {
+					return err
+				}
+			}
 			if step.Activity != "" {
 				// Inject padding into the activity input if specified
 				injectPadding(step.Input, step.PaddingSize)

workflows/workflow_test.go

@@ -3,6 +3,7 @@ package workflows
 import (
 	"context"
 	"testing"
+	"time"
 
 	"github.com/temporalio/benchmark-workers/activities"
 
@@ -37,6 +38,33 @@ func TestDSLWorkflow(t *testing.T) {
 	require.Equal(t, 6, echoCount, "Echo activity should be called 6 times")
 }
 
+func TestDSLWorkflowWithTimerSleep(t *testing.T) {
+	ts := &testsuite.WorkflowTestSuite{}
+	env := ts.NewTestWorkflowEnvironment()
+
+	env.RegisterActivityWithOptions(activities.EchoActivity, activity.RegisterOptions{Name: "Echo"})
+	var echoCount int
+	env.OnActivity("Echo", mock.Anything, mock.Anything).Return(func(ctx context.Context, input activities.EchoActivityInput) (string, error) {
+		echoCount++
+		return input.Message, nil
+	})
+
+	steps := []DSLStep{
+		{SleepSeconds: 2, Repeat: 3},
+		{Activity: "Echo", Input: map[string]interface{}{"Message": "test"}},
+	}
+
+	startTime := env.Now()
+	env.ExecuteWorkflow(DSLWorkflow, steps)
+
+	require.True(t, env.IsWorkflowCompleted())
+	require.NoError(t, env.GetWorkflowError())
+	require.Equal(t, 1, echoCount, "Echo activity should be called once")
+	// The timer sleeps run via workflow.Sleep (durable timers) and are
+	// fast-forwarded by the test env's time skipping: 3 repeats * 2s.
+	require.Equal(t, 6*time.Second, env.Now().Sub(startTime))
+}
+
 func TestDSLWorkflowWithPadding(t *testing.T) {
 	ts := &testsuite.WorkflowTestSuite{}
 	env := ts.NewTestWorkflowEnvironment()