From 6ea7f3e4c0eddeb6c76f01146892009e674c6257 Mon Sep 17 00:00:00 2001
From: Harry Bagdi <harrybagdi@gmail.com>
Date: Tue, 11 Sep 2018 15:56:11 -0700
Subject: [PATCH] feat: allow configuring KongPlugins using
 `plugins.konghq.com`

This change allows an end-user to configure a plugin on a route or a
service in Kong using a new annotaion: `plugins.konghq.com`.
This annotations should contain a CSV list of KongPlugin CR names which
should be applied.

This should make it easier for the end user to configure plugins on
Ingress resources and k8s Services.

The old way of configuration plugins:
`<plugin-name>.plugin.konghq.com: <KongPlugin CR name>`
is deprecated but still supported, giving users time to migrate to new
annotations. There will be a documentation commit made in future to
reflect the same.
---
 internal/ingress/controller/kong.go | 59 +++++++++++++++++------------
 1 file changed, 35 insertions(+), 24 deletions(-)

diff --git a/internal/ingress/controller/kong.go b/internal/ingress/controller/kong.go
index 4a5d255cb9..be1abbc577 100644
--- a/internal/ingress/controller/kong.go
+++ b/internal/ingress/controller/kong.go
@@ -273,6 +273,37 @@ func syncTargets(upstream string, ingressEndpopint *ingress.Backend, client *kon
 	return nil
 }
 
+// getPluginsFromAnnotations extracts plugins to be applied on an ingress/service from annotations
+func (n *NGINXController) getPluginsFromAnnotations(namespace string, anns map[string]string) (map[string]*pluginv1.KongPlugin, error) {
+	pluginAnnotations := annotations.ExtractKongPluginAnnotations(anns)
+	pluginsInk8s := make(map[string]*pluginv1.KongPlugin)
+	for plugin, crdNames := range pluginAnnotations {
+		for _, crdName := range crdNames {
+			// search configured plugin CRD in k8s
+			k8sPlugin, err := n.store.GetKongPlugin(namespace, crdName)
+			if err != nil {
+				return nil, errors.Wrap(err, fmt.Sprintf("searching plugin KongPlugin %v", crdName))
+			}
+			pluginsInk8s[plugin] = k8sPlugin
+		}
+	}
+	pluginList := annotations.ExtractKongPluginsFromAnnotations(anns)
+	// override plugins configured by new annotation
+	for _, plugin := range pluginList {
+		k8sPlugin, err := n.store.GetKongPlugin(namespace, plugin)
+		if err != nil {
+			return nil, errors.Wrap(err, fmt.Sprintf("searching plugin KongPlugin %v", plugin))
+		}
+		// ignore plugins with no name
+		if k8sPlugin.PluginName == "" {
+			glog.Errorf("KongPlugin Custom resource '%v' has no `plugin` property, the plugin will not be configured", k8sPlugin.Name)
+			continue
+		}
+		pluginsInk8s[k8sPlugin.PluginName] = k8sPlugin
+	}
+	return pluginsInk8s, nil
+}
+
 // syncServices reconciles the state between the ingress controller and
 // kong services. After the synchronization of services we also check
 // if there was any changes to the kong plugins applied to the service
@@ -409,18 +440,8 @@ func (n *NGINXController) syncServices(ingressCfg *ingress.Configuration) (bool,
 			}
 
 			// Get plugin annotations from k8s, these plugins should be configured for this service
-			pluginAnnotations := annotations.ExtractKongPluginAnnotations(location.Service.GetAnnotations())
-			pluginsInk8s := make(map[string]*pluginv1.KongPlugin)
-			for plugin, crdNames := range pluginAnnotations {
-				for _, crdName := range crdNames {
-					// search configured plugin CRD in k8s
-					k8sPlugin, err := n.store.GetKongPlugin(location.Ingress.Namespace, crdName)
-					if err != nil {
-						return false, errors.Wrap(err, fmt.Sprintf("searching plugin KongPlugin %v", crdName))
-					}
-					pluginsInk8s[plugin] = k8sPlugin
-				}
-			}
+			anns := location.Service.GetAnnotations()
+			pluginsInk8s, err := n.getPluginsFromAnnotations(location.Ingress.Namespace, anns)
 
 			// Get plugins configured in Kong currently
 			plugins, err := client.Plugins().GetAllByService(svc.ID)
@@ -830,18 +851,8 @@ func (n *NGINXController) syncRoutes(ingressCfg *ingress.Configuration) (bool, e
 				continue
 			}
 
-			pluginAnnotations := annotations.ExtractKongPluginAnnotations(location.Ingress.GetAnnotations())
-			pluginsInk8s := make(map[string]*pluginv1.KongPlugin)
-			for plugin, crdNames := range pluginAnnotations {
-				for _, crdName := range crdNames {
-					// search configured plugin CRD in k8s
-					k8sPlugin, err := n.store.GetKongPlugin(location.Ingress.Namespace, crdName)
-					if err != nil {
-						return false, errors.Wrap(err, fmt.Sprintf("searching plugin KongPlugin %v", crdName))
-					}
-					pluginsInk8s[plugin] = k8sPlugin
-				}
-			}
+			anns := location.Ingress.GetAnnotations()
+			pluginsInk8s, err := n.getPluginsFromAnnotations(location.Ingress.Namespace, anns)
 
 			// Get plugins configured in Kong currently
 			plugins, err := client.Plugins().GetAllByRoute(route.ID)