pospt prep

infrastructure/scheduler/scheduler.go

@@ -3,6 +3,7 @@ package scheduler
 import (
 	"errors"
 	"fmt"
+	"oc-scheduler/conf"
 	"oc-scheduler/infrastructure/planner"
 	"oc-scheduler/infrastructure/scheduling_resources"
 	infUtils "oc-scheduler/infrastructure/utils"
@@ -20,8 +21,6 @@ import (
 	"github.com/robfig/cron"
 )
 
-const asapBuffer = 2 * time.Minute
-
 // Schedule holds a resolved start/end pair for a single execution slot.
 type Schedule struct {
 	Start time.Time
@@ -80,9 +79,18 @@ func (ws *WorkflowSchedule) Check(wfID string, asap bool, preemption bool, reque
 	}
 	wf := obj.(*workflow.Workflow)
 
+	prepLead := conf.GetConfig().PrepLead()
 	start := ws.Start
 	if asap || start.IsZero() {
-		start = time.Now().UTC().Add(asapBuffer)
+		start = time.Now().UTC().Add(prepLead)
+	} else if start.Before(time.Now().UTC().Add(prepLead)) {
+		// Explicit date is within the prep window — impossible to guarantee on time.
+		return nil, fmt.Errorf(
+			"start date %s is too soon: minimum lead time is %s (earliest: %s)",
+			start.Format(time.RFC3339),
+			prepLead,
+			time.Now().UTC().Add(prepLead).Format(time.RFC3339),
+		)
 	}
 
 	end := ws.End