Issue 30 tcp http support (#31)

* BorderClient basics

* Documentation updates

* About to apply a broad rename

* Rename to support library differences

* Add HTTP Border Client

* Add TCP Border Client

* Use pointers

* Synchronizer uses BorderClient

* Translator extracts client type from Annotations, default when not found

* Copy Paste issue, TCP Border Client need to use the *Stream methods

* Fix stupid mistake in the refactor

* Put an interface between NKL and the NGINX Plus client Upstream objects

DESIGN.md

@@ -17,10 +17,11 @@ stateDiagram-v2
     Handler --> Translator
     Translator --> Handler
     Handler --> Synchronizer : "nkl-synchronizer queue"
-    Synchronizer --> NGINXPlusLB1
-    Synchronizer --> NGINXPlusLB2
-    Synchronizer --> NGINXPlusLB...
-    Synchronizer --> NGINXPlusLBn
+    Synchronizer --> BorderClient : "HttpBorderClient | TcpBorderClient"
+    BorderClient --> NGINXPlusLB1
+    BorderClient --> NGINXPlusLB2
+    BorderClient --> NGINXPlusLB...
+    BorderClient --> NGINXPlusLBn
 ```
 
 ### Settings

internal/application/application_common_test.go

@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2023 F5 Inc. All rights reserved.
+ * Use of this source code is governed by the Apache License that can be found in the LICENSE file.
+ */
+
+package application
+
+import (
+	"errors"
+	"github.com/nginxinc/kubernetes-nginx-ingress/internal/core"
+	"github.com/nginxinc/kubernetes-nginx-ingress/test/mocks"
+)
+
+const (
+	deletedEventType = core.Deleted
+	createEventType  = core.Created
+	upstreamName     = "upstreamName"
+	server           = "server"
+)
+
+func buildTerrorizingBorderClient(clientType string) (Interface, *mocks.MockNginxClient, error) {
+	nginxClient := mocks.NewErroringMockClient(errors.New(`something went horribly horribly wrong`))
+	bc, err := NewBorderClient(clientType, nginxClient)
+
+	return bc, nginxClient, err
+}
+
+func buildBorderClient(clientType string) (Interface, *mocks.MockNginxClient, error) {
+	nginxClient := mocks.NewMockNginxClient()
+	bc, err := NewBorderClient(clientType, nginxClient)
+
+	return bc, nginxClient, err
+}
+
+func buildServerUpdateEvent(eventType core.EventType, clientType string) *core.ServerUpdateEvent {
+	upstreamServers := core.UpstreamServers{
+		{
+			Host: server,
+		},
+	}
+
+	return core.NewServerUpdateEvent(eventType, upstreamName, clientType, upstreamServers)
+}

internal/application/application_constants.go

@@ -0,0 +1,11 @@
+/*
+ * Copyright (c) 2023 F5 Inc. All rights reserved.
+ * Use of this source code is governed by the Apache License that can be found in the LICENSE file.
+ */
+
+package application
+
+const (
+	ClientTypeTcp  = "tcp"
+	ClientTypeHttp = "http"
+)

internal/application/border_client.go

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2023 F5 Inc. All rights reserved.
+ * Use of this source code is governed by the Apache License that can be found in the LICENSE file.
+ */
+
+package application
+
+import (
+	"fmt"
+	"github.com/nginxinc/kubernetes-nginx-ingress/internal/core"
+	"github.com/sirupsen/logrus"
+)
+
+type Interface interface {
+	Update(*core.ServerUpdateEvent) error
+	Delete(*core.ServerUpdateEvent) error
+}
+
+type BorderClient struct {
+}
+
+// NewBorderClient Returns a NullBorderClient if the type is unknown, this avoids panics due to nil pointer dereferences.
+func NewBorderClient(clientType string, borderClient interface{}) (Interface, error) {
+	logrus.Debugf(`NewBorderClient for type: %s`, clientType)
+
+	switch clientType {
+	case "tcp":
+		return NewTcpBorderClient(borderClient)
+
+	case "http":
+		return NewHttpBorderClient(borderClient)
+
+	default:
+		borderClient, _ := NewNullBorderClient()
+		return borderClient, fmt.Errorf(`unknown border client type: %s`, clientType)
+	}
+}

internal/application/border_client_test.go

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2023 F5 Inc. All rights reserved.
+ * Use of this source code is governed by the Apache License that can be found in the LICENSE file.
+ */
+
+package application
+
+import (
+	"github.com/nginxinc/kubernetes-nginx-ingress/test/mocks"
+	"testing"
+)
+
+func TestBorderClient_CreatesHttpBorderClient(t *testing.T) {
+	borderClient := mocks.MockNginxClient{}
+	client, err := NewBorderClient("http", borderClient)
+	if err != nil {
+		t.Errorf(`error creating border client: %v`, err)
+	}
+
+	if _, ok := client.(*HttpBorderClient); !ok {
+		t.Errorf(`expected client to be of type HttpBorderClient`)
+	}
+}
+
+func TestBorderClient_CreatesTcpBorderClient(t *testing.T) {
+	borderClient := mocks.MockNginxClient{}
+	client, err := NewBorderClient("tcp", borderClient)
+	if err != nil {
+		t.Errorf(`error creating border client: %v`, err)
+	}
+
+	if _, ok := client.(*TcpBorderClient); !ok {
+		t.Errorf(`expected client to be of type TcpBorderClient`)
+	}
+}
+
+func TestBorderClient_UnknownClientType(t *testing.T) {
+	unknownClientType := "unknown"
+	borderClient := mocks.MockNginxClient{}
+	client, err := NewBorderClient(unknownClientType, borderClient)
+	if err == nil {
+		t.Errorf(`expected error creating border client`)
+	}
+
+	if err.Error() != `unknown border client type: unknown` {
+		t.Errorf(`expected error to be 'unknown border client type: unknown', got: %v`, err)
+	}
+
+	if _, ok := client.(*NullBorderClient); !ok {
+		t.Errorf(`expected client to be of type NullBorderClient`)
+	}
+}

internal/application/doc.go

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2023 F5 Inc. All rights reserved.
+ * Use of this source code is governed by the Apache License that can be found in the LICENSE file.
+ */
+
+/*
+Package application includes support for applying updates to the Border servers.
+
+"Border TcpServers" are the servers that are exposed to the outside world and direct traffic into the cluster.
+At this time the only supported Border TcpServers are NGINX Plus servers. The BorderClient module defines
+an interface that can be implemented to support other Border Server types.
+
+- HttpBorderClient: updates NGINX Plus servers using HTTP Upstream methods on the NGINX Plus API.
+- TcpBorderClient: updates NGINX Plus servers using Stream Upstream methods on the NGINX Plus API.
+
+Selection of the appropriate client is based on the Annotations present on the NodePort Service definition.
+*/
+
+package application

internal/application/http_border_client.go

@@ -0,0 +1,63 @@
+/*
+ * Copyright 2023 F5 Inc. All rights reserved.
+ * Use of this source code is governed by the Apache License that can be found in the LICENSE file.
+ */
+
+package application
+
+import (
+	"fmt"
+	"github.com/nginxinc/kubernetes-nginx-ingress/internal/core"
+	nginxClient "github.com/nginxinc/nginx-plus-go-client/client"
+)
+
+type HttpBorderClient struct {
+	BorderClient
+	nginxClient NginxClientInterface
+}
+
+func NewHttpBorderClient(client interface{}) (Interface, error) {
+	ngxClient, ok := client.(NginxClientInterface)
+	if !ok {
+		return nil, fmt.Errorf(`expected a NginxClientInterface, got a %v`, client)
+	}
+
+	return &HttpBorderClient{
+		nginxClient: ngxClient,
+	}, nil
+}
+
+func (hbc *HttpBorderClient) Update(event *core.ServerUpdateEvent) error {
+	httpUpstreamServers := asNginxHttpUpstreamServers(event.UpstreamServers)
+	_, _, _, err := hbc.nginxClient.UpdateHTTPServers(event.UpstreamName, httpUpstreamServers)
+	if err != nil {
+		return fmt.Errorf(`error occurred updating the nginx+ upstream server: %w`, err)
+	}
+
+	return nil
+}
+
+func (hbc *HttpBorderClient) Delete(event *core.ServerUpdateEvent) error {
+	err := hbc.nginxClient.DeleteHTTPServer(event.UpstreamName, event.UpstreamServers[0].Host)
+	if err != nil {
+		return fmt.Errorf(`error occurred deleting the nginx+ upstream server: %w`, err)
+	}
+
+	return nil
+}
+
+func asNginxHttpUpstreamServer(server *core.UpstreamServer) nginxClient.UpstreamServer {
+	return nginxClient.UpstreamServer{
+		Server: server.Host,
+	}
+}
+
+func asNginxHttpUpstreamServers(servers core.UpstreamServers) []nginxClient.UpstreamServer {
+	var upstreamServers []nginxClient.UpstreamServer
+
+	for _, server := range servers {
+		upstreamServers = append(upstreamServers, asNginxHttpUpstreamServer(server))
+	}
+
+	return upstreamServers
+}

internal/application/http_border_client_test.go

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2023 F5 Inc. All rights reserved.
+ * Use of this source code is governed by the Apache License that can be found in the LICENSE file.
+ */
+
+package application
+
+import (
+	"testing"
+)
+
+func TestHttpBorderClient_Delete(t *testing.T) {
+	event := buildServerUpdateEvent(deletedEventType, ClientTypeHttp)
+	borderClient, nginxClient, err := buildBorderClient(ClientTypeHttp)
+	if err != nil {
+		t.Fatalf(`error occurred creating a new border client: %v`, err)
+	}
+
+	err = borderClient.Delete(event)
+	if err != nil {
+		t.Fatalf(`error occurred deleting the nginx+ upstream server: %v`, err)
+	}
+
+	if !nginxClient.CalledFunctions["DeleteHTTPServer"] {
+		t.Fatalf(`expected DeleteHTTPServer to be called`)
+	}
+}
+
+func TestHttpBorderClient_Update(t *testing.T) {
+	event := buildServerUpdateEvent(createEventType, ClientTypeHttp)
+	borderClient, nginxClient, err := buildBorderClient(ClientTypeHttp)
+	if err != nil {
+		t.Fatalf(`error occurred creating a new border client: %v`, err)
+	}
+
+	err = borderClient.Update(event)
+	if err != nil {
+		t.Fatalf(`error occurred deleting the nginx+ upstream server: %v`, err)
+	}
+
+	if !nginxClient.CalledFunctions["UpdateHTTPServers"] {
+		t.Fatalf(`expected UpdateHTTPServers to be called`)
+	}
+}
+
+func TestHttpBorderClient_BadNginxClient(t *testing.T) {
+	var emptyInterface interface{}
+	_, err := NewBorderClient(ClientTypeHttp, emptyInterface)
+	if err == nil {
+		t.Fatalf(`expected an error to occur when creating a new border client`)
+	}
+}
+
+func TestHttpBorderClient_DeleteReturnsError(t *testing.T) {
+	event := buildServerUpdateEvent(deletedEventType, ClientTypeHttp)
+	borderClient, _, err := buildTerrorizingBorderClient(ClientTypeHttp)
+	if err != nil {
+		t.Fatalf(`error occurred creating a new border client: %v`, err)
+	}
+
+	err = borderClient.Delete(event)
+
+	if err == nil {
+		t.Fatalf(`expected an error to occur when deleting the nginx+ upstream server`)
+	}
+}
+
+func TestHttpBorderClient_UpdateReturnsError(t *testing.T) {
+	event := buildServerUpdateEvent(createEventType, ClientTypeHttp)
+	borderClient, _, err := buildTerrorizingBorderClient(ClientTypeHttp)
+	if err != nil {
+		t.Fatalf(`error occurred creating a new border client: %v`, err)
+	}
+
+	err = borderClient.Update(event)
+
+	if err == nil {
+		t.Fatalf(`expected an error to occur when deleting the nginx+ upstream server`)
+	}
+}

internal/application/nginx_client_interface.go

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2023 F5 Inc. All rights reserved.
+ * Use of this source code is governed by the Apache License that can be found in the LICENSE file.
+ */
+
+package application
+
+import nginxClient "github.com/nginxinc/nginx-plus-go-client/client"
+
+type NginxClientInterface interface {
+	DeleteStreamServer(upstream string, server string) error
+	UpdateStreamServers(upstream string, servers []nginxClient.StreamUpstreamServer) ([]nginxClient.StreamUpstreamServer, []nginxClient.StreamUpstreamServer, []nginxClient.StreamUpstreamServer, error)
+
+	DeleteHTTPServer(upstream string, server string) error
+	UpdateHTTPServers(upstream string, servers []nginxClient.UpstreamServer) ([]nginxClient.UpstreamServer, []nginxClient.UpstreamServer, []nginxClient.UpstreamServer, error)
+}

internal/application/null_border_client.go

@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2023 F5 Inc. All rights reserved.
+ * Use of this source code is governed by the Apache License that can be found in the LICENSE file.
+ */
+
+package application
+
+import (
+	"github.com/nginxinc/kubernetes-nginx-ingress/internal/core"
+	"github.com/sirupsen/logrus"
+)
+
+type NullBorderClient struct {
+}
+
+func NewNullBorderClient() (Interface, error) {
+	return &NullBorderClient{}, nil
+}
+
+func (nbc *NullBorderClient) Update(_ *core.ServerUpdateEvent) error {
+	logrus.Warn("NullBorderClient.Update called")
+	return nil
+}
+
+func (nbc *NullBorderClient) Delete(_ *core.ServerUpdateEvent) error {
+	logrus.Warn("NullBorderClient.Delete called")
+	return nil
+}

internal/application/null_border_client_test.go

@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2023 F5 Inc. All rights reserved.
+ * Use of this source code is governed by the Apache License that can be found in the LICENSE file.
+ */
+
+package application
+
+import "testing"
+
+func TestNullBorderClient_Delete(t *testing.T) {
+	client := NullBorderClient{}
+	err := client.Delete(nil)
+	if err != nil {
+		t.Errorf(`expected no error deleting border client, got: %v`, err)
+	}
+}
+
+func TestNullBorderClient_Update(t *testing.T) {
+	client := NullBorderClient{}
+	err := client.Update(nil)
+	if err != nil {
+		t.Errorf(`expected no error updating border client, got: %v`, err)
+	}
+}