From 181f56f026078cb58871d7fe3002ffadde8c256c Mon Sep 17 00:00:00 2001
From: dougbtv <dosmith@redhat.com>
Date: Tue, 14 May 2024 11:14:21 -0400
Subject: [PATCH] Thick plugin should not wait for API readiness on CNI DEL

This modifies the behavior on CNI DEL for the thick plugin to just check once for API readiness, as opposed to waiting.
---
 pkg/server/api/api.go  |  9 +++++++++
 pkg/server/api/shim.go | 15 +++++++++------
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/pkg/server/api/api.go b/pkg/server/api/api.go
index b9228f0dc..995676c38 100644
--- a/pkg/server/api/api.go
+++ b/pkg/server/api/api.go
@@ -104,3 +104,12 @@ func WaitUntilAPIReady(socketPath string) error {
 		return err == nil, nil
 	})
 }
+
+// CheckAPIReadyNow checks API readiness once
+func CheckAPIReadyNow(socketPath string) error {
+	_, err := DoCNI(GetAPIEndpoint(MultusHealthAPIEndpoint), nil, SocketPath(socketPath))
+	if err != nil {
+		return fmt.Errorf("CheckAPIReadyNow: Daemon not reachable over socketfile: %v", err)
+	}
+	return nil
+}
diff --git a/pkg/server/api/shim.go b/pkg/server/api/shim.go
index 168404ea4..497a9e5ae 100644
--- a/pkg/server/api/shim.go
+++ b/pkg/server/api/shim.go
@@ -40,9 +40,12 @@ type ShimNetConf struct {
 	LogToStderr     bool   `json:"logToStderr,omitempty"`
 }
 
+// Define a type for API readiness check functions
+type APIReadyCheckFunc func(string) error
+
 // CmdAdd implements the CNI spec ADD command handler
 func CmdAdd(args *skel.CmdArgs) error {
-	response, cniVersion, err := postRequest(args)
+	response, cniVersion, err := postRequest(args, WaitUntilAPIReady)
 	if err != nil {
 		return logging.Errorf("CmdAdd (shim): %v", err)
 	}
@@ -53,7 +56,7 @@ func CmdAdd(args *skel.CmdArgs) error {
 
 // CmdCheck implements the CNI spec CHECK command handler
 func CmdCheck(args *skel.CmdArgs) error {
-	_, _, err := postRequest(args)
+	_, _, err := postRequest(args, WaitUntilAPIReady)
 	if err != nil {
 		return logging.Errorf("CmdCheck (shim): %v", err)
 	}
@@ -63,7 +66,7 @@ func CmdCheck(args *skel.CmdArgs) error {
 
 // CmdDel implements the CNI spec DEL command handler
 func CmdDel(args *skel.CmdArgs) error {
-	_, _, err := postRequest(args)
+	_, _, err := postRequest(args, CheckAPIReadyNow)
 	if err != nil {
 		// No error in DEL (as of CNI spec)
 		logging.Errorf("CmdDel (shim): %v", err)
@@ -71,14 +74,14 @@ func CmdDel(args *skel.CmdArgs) error {
 	return nil
 }
 
-func postRequest(args *skel.CmdArgs) (*Response, string, error) {
+func postRequest(args *skel.CmdArgs, readinessCheck APIReadyCheckFunc) (*Response, string, error) {
 	multusShimConfig, err := shimConfig(args.StdinData)
 	if err != nil {
 		return nil, "", fmt.Errorf("invalid CNI configuration passed to multus-shim: %w", err)
 	}
 
-	// check API readiness
-	if err := WaitUntilAPIReady(multusShimConfig.MultusSocketDir); err != nil {
+	// Execute the readiness check as necessary (e.g. don't wait on CNI DEL)
+	if err := readinessCheck(multusShimConfig.MultusSocketDir); err != nil {
 		return nil, multusShimConfig.CNIVersion, err
 	}