fix(manager) lock client creation

Add a mutex and lock it when creating Kong admin clients. Attempting to
create multiple workspaced clients simultaneously can result in a race
condition where both clients check for the workspace before either
creates it, both clients will attempt to create the workspace, and the
second client to attempt creation will hit a unique violation.

internal/manager/setup.go

@@ -5,6 +5,7 @@ import (
  "fmt"
  "os"
  "strings"
+ "sync"
  "time"
 
  "github.com/bombsimon/logrusr"
@@ -24,6 +25,8 @@ import (
  "github.com/kong/kubernetes-ingress-controller/v2/internal/util"
 )
 
+var clientSetup sync.Mutex
+
 // -----------------------------------------------------------------------------
 // Controller Manager - Setup Utility Functions
 // -----------------------------------------------------------------------------
@@ -92,7 +95,9 @@ func setupControllerOptions(logger logr.Logger, c *Config, scheme *runtime.Schem
 }
 
 func setupKongConfig(ctx context.Context, logger logr.Logger, c *Config) (sendconfig.Kong, error) {
+ clientSetup.Lock()
  kongClient, err := c.GetKongClient(ctx)
+ clientSetup.Unlock()
  if err != nil {
  return sendconfig.Kong{}, fmt.Errorf("unable to build kong api client: %w", err)
  }
@@ -166,7 +171,9 @@ func setupAdmissionServer(ctx context.Context, managerConfig *Config, managerCli
 
  logger := log.WithField("component", "admission-server")
 
+ clientSetup.Lock()
  kongclient, err := managerConfig.GetKongClient(ctx)
+ clientSetup.Unlock()
  if err != nil {
  return err
  }