From 89c64fdb9ad0166c39a77b0f9fcc6f4d5fdc10ce Mon Sep 17 00:00:00 2001
From: dougbtv <dosmith@redhat.com>
Date: Tue, 20 Feb 2024 13:58:51 -0500
Subject: [PATCH] Skips checking for readiness on CNI DEL (and instead warns)

Because deletes should favor a successful path, the readiness check should be skipped for pod removals.

This can cause an issue where there's pods pending deletes and that might impact scheduling of a pod that may be necessary in order to set the readiness indicator.

Adds a new method  to check for readiness indicator alone in order to immediately log a warning.
---
 pkg/multus/multus.go |  9 +++++++--
 pkg/types/conf.go    | 27 ++++++++++++++++++++++++---
 2 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/pkg/multus/multus.go b/pkg/multus/multus.go
index e9ecc1ed1..49d55e271 100644
--- a/pkg/multus/multus.go
+++ b/pkg/multus/multus.go
@@ -815,8 +815,13 @@ func CmdDel(args *skel.CmdArgs, exec invoke.Exec, kubeClient *k8s.ClientInfo) er
 	}
 
 	if in.ReadinessIndicatorFile != "" {
-		if err := types.GetReadinessIndicatorFile(in.ReadinessIndicatorFile); err != nil {
-			return cmdErr(k8sArgs, "PollImmediate error waiting for ReadinessIndicatorFile (on del): %v", err)
+		readinessfileexists, err := types.ReadinessIndicatorExistsNow(in.ReadinessIndicatorFile)
+		if err != nil {
+			return cmdErr(k8sArgs, "error checking readinessindicatorfile on CNI DEL @ %v: %v", in.ReadinessIndicatorFile, err)
+		} else {
+			if !readinessfileexists {
+				logging.Verbosef("warning: readinessindicatorfile @ %v does not exist on CNI DEL", in.ReadinessIndicatorFile)
+			}
 		}
 	}
 
diff --git a/pkg/types/conf.go b/pkg/types/conf.go
index 4402b4ec7..e85a4a96d 100644
--- a/pkg/types/conf.go
+++ b/pkg/types/conf.go
@@ -20,17 +20,17 @@ import (
 	"fmt"
 	"net"
 	"os"
+	"path/filepath"
 	"strings"
 	"time"
 
-	utilwait "k8s.io/apimachinery/pkg/util/wait"
-
 	"github.com/containernetworking/cni/libcni"
 	"github.com/containernetworking/cni/pkg/skel"
 	cni100 "github.com/containernetworking/cni/pkg/types/100"
 	"github.com/containernetworking/cni/pkg/version"
 	nadutils "github.com/k8snetworkplumbingwg/network-attachment-definition-client/pkg/utils"
 	"gopkg.in/k8snetworkplumbingwg/multus-cni.v4/pkg/logging"
+	utilwait "k8s.io/apimachinery/pkg/util/wait"
 )
 
 const (
@@ -610,7 +610,12 @@ func CheckSystemNamespaces(namespace string, systemNamespaces []string) bool {
 }
 
 // GetReadinessIndicatorFile waits for readinessIndicatorFile
-func GetReadinessIndicatorFile(readinessIndicatorFile string) error {
+func GetReadinessIndicatorFile(readinessIndicatorFileRaw string) error {
+	readinessIndicatorFile, err := filepath.Abs(readinessIndicatorFileRaw)
+	if err != nil {
+		return fmt.Errorf("failed to get absolute path of readinessIndicatorFile: %v", err)
+	}
+
 	pollDuration := 1000 * time.Millisecond
 	pollTimeout := 45 * time.Second
 	return utilwait.PollImmediate(pollDuration, pollTimeout, func() (bool, error) {
@@ -618,3 +623,19 @@ func GetReadinessIndicatorFile(readinessIndicatorFile string) error {
 		return err == nil, nil
 	})
 }
+
+func ReadinessIndicatorExistsNow(readinessIndicatorFileRaw string) (bool, error) {
+	readinessIndicatorFile, err := filepath.Abs(readinessIndicatorFileRaw)
+	if err != nil {
+		return false, fmt.Errorf("failed to get absolute path of readinessIndicatorFile: %v", err)
+	}
+
+	_, err = os.Stat(readinessIndicatorFile)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return false, nil
+		}
+		return false, err
+	}
+	return true, nil
+}