From f8a6e69ef37aabad3e4ed54e4617d1dce668f64d Mon Sep 17 00:00:00 2001
From: mr <morgane.roques@irt-saintexupery.com>
Date: Thu, 26 Mar 2026 11:15:02 +0100
Subject: [PATCH] pospt prep

---
 conf/config.go                        | 26 ++++++++++++++++++++------
 infrastructure/scheduler/scheduler.go | 14 +++++++++++---
 main.go                               |  1 +
 3 files changed, 32 insertions(+), 9 deletions(-)

diff --git a/conf/config.go b/conf/config.go
index 5462548..161abb6 100644
--- a/conf/config.go
+++ b/conf/config.go
@@ -1,13 +1,27 @@
 package conf
 
-import "sync"
+import (
+	"sync"
+	"time"
+)
 
 type Config struct {
-	KubeHost string
-	KubePort string
-	KubeCA   string
-	KubeCert string
-	KubeData string
+	KubeHost        string
+	KubePort        string
+	KubeCA          string
+	KubeCert        string
+	KubeData        string
+	// PrepLeadSeconds must match oc-schedulerd's PREP_LEAD_SECONDS.
+	// Used both as the ASAP buffer and as the minimum allowed lead time
+	// when validating explicit booking start dates.
+	PrepLeadSeconds int
+}
+
+func (c *Config) PrepLead() time.Duration {
+	if c.PrepLeadSeconds <= 0 {
+		return 2 * time.Minute
+	}
+	return time.Duration(c.PrepLeadSeconds) * time.Second
 }
 
 var instance *Config
diff --git a/infrastructure/scheduler/scheduler.go b/infrastructure/scheduler/scheduler.go
index d7ff695..cd325d2 100644
--- a/infrastructure/scheduler/scheduler.go
+++ b/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
diff --git a/main.go b/main.go
index 9642a68..2f3f620 100644
--- a/main.go
+++ b/main.go
@@ -13,6 +13,7 @@ const appname = "oc-scheduler"
 
 func main() {
 	o := oclib.GetConfLoader(appname)
+	conf.GetConfig().PrepLeadSeconds = o.GetIntDefault("PREP_LEAD_SECONDS", 120)
 	conf.GetConfig().KubeHost = o.GetStringDefault("KUBERNETES_SERVICE_HOST", "kubernetes.default.svc.cluster.local")
 	conf.GetConfig().KubePort = o.GetStringDefault("KUBERNETES_SERVICE_PORT", "6443")