[v9.5.x] Licensing: Pass func to update env variables when starting plugin (#74681)

* Licensing: Pass func to update env variables when starting plugin (#74620)

(cherry picked from commit 5e0b20266e)

pkg/plugins/backendplugin/backendplugin.go

@@ -6,4 +6,4 @@ import (
 )
 
 // PluginFactoryFunc is a function type for creating a Plugin.
-type PluginFactoryFunc func(pluginID string, logger log.Logger, env []string) (Plugin, error)
+type PluginFactoryFunc func(pluginID string, logger log.Logger, env func() []string) (Plugin, error)

pkg/plugins/backendplugin/coreplugin/core_plugin.go

@@ -21,7 +21,7 @@ type corePlugin struct {
 
 // New returns a new backendplugin.PluginFactoryFunc for creating a core (built-in) backendplugin.Plugin.
 func New(opts backend.ServeOpts) backendplugin.PluginFactoryFunc {
-	return func(pluginID string, logger log.Logger, env []string) (backendplugin.Plugin, error) {
+	return func(pluginID string, logger log.Logger, _ func() []string) (backendplugin.Plugin, error) {
 		return &corePlugin{
 			pluginID:            pluginID,
 			logger:              logger,

pkg/plugins/backendplugin/grpcplugin/grpc_plugin.go

@@ -33,12 +33,12 @@ type grpcPlugin struct {
 
 // newPlugin allocates and returns a new gRPC (external) backendplugin.Plugin.
 func newPlugin(descriptor PluginDescriptor) backendplugin.PluginFactoryFunc {
-	return func(pluginID string, logger log.Logger, env []string) (backendplugin.Plugin, error) {
+	return func(pluginID string, logger log.Logger, env func() []string) (backendplugin.Plugin, error) {
 		return &grpcPlugin{
 			descriptor: descriptor,
 			logger:     logger,
 			clientFactory: func() *plugin.Client {
-				return plugin.NewClient(newClientConfig(descriptor.executablePath, env, logger, descriptor.versionedPlugins))
+				return plugin.NewClient(newClientConfig(descriptor.executablePath, env(), logger, descriptor.versionedPlugins))
 			},
 		}, nil
 	}

pkg/plugins/manager/fakes/fakes.go

@@ -312,7 +312,7 @@ func NewFakeBackendProcessProvider() *FakeBackendProcessProvider {
 
 func (pr *FakeBackendProcessProvider) BackendFactory(_ context.Context, p *plugins.Plugin) backendplugin.PluginFactoryFunc {
 	pr.Requested[p.ID]++
-	return func(pluginID string, _ log.Logger, _ []string) (backendplugin.Plugin, error) {
+	return func(pluginID string, _ log.Logger, _ func() []string) (backendplugin.Plugin, error) {
 		pr.Invoked[pluginID]++
 		return &FakePluginClient{}, nil
 	}

pkg/plugins/manager/loader/initializer/initializer.go

@@ -37,7 +37,10 @@ func (i *Initializer) Initialize(ctx context.Context, p *plugins.Plugin) error {
 			return fmt.Errorf("could not find backend factory for plugin")
 		}
 
-		if backendClient, err := backendFactory(p.ID, p.Logger(), i.envVars(p)); err != nil {
+		// this will ensure that the env variables are calculated every time a plugin is started
+		envFunc := func() []string { return i.envVars(p) }
+
+		if backendClient, err := backendFactory(p.ID, p.Logger(), envFunc); err != nil {
 			return err
 		} else {
 			p.RegisterClient(backendClient)

pkg/plugins/manager/loader/initializer/initializer_test.go

@@ -422,7 +422,7 @@ type fakeBackendProvider struct {
 }
 
 func (f *fakeBackendProvider) BackendFactory(_ context.Context, _ *plugins.Plugin) backendplugin.PluginFactoryFunc {
-	return func(_ string, _ log.Logger, _ []string) (backendplugin.Plugin, error) {
+	return func(_ string, _ log.Logger, _ func() []string) (backendplugin.Plugin, error) {
 		return f.plugin, nil
 	}
 }