Refactor AWS CDK L3 Components (#52)

* refactor cdk components previous interface of CDK components was tuned for the simplicity on creating standalone apps. The interface was not optimal for integrating event handlers into large cdk app.
fogfish · Mar 23, 2024 · 3990593 · 3990593
1 parent 0efe5b8
commit 3990593
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Showing 20 changed files with 501 additions and 586 deletions.
diff --git a/README.md b/README.md
@@ -375,16 +375,24 @@ package main
 
 import (
   "github.com/fogfish/scud"
-  "github.com/fogfish/swarm/queue/eventbridge"
+  "github.com/fogfish/swarm/broker/eventbridge"
 )
 
 func main() {
-  app := eventbridge.NewServerlessApp()
+  app := awscdk.NewApp(nil)
+  stack := awscdk.NewStack(app, jsii.String("swarm-example-eventbridge"),
+    &awscdk.StackProps{
+      Env: &awscdk.Environment{
+        Account: jsii.String(os.Getenv("CDK_DEFAULT_ACCOUNT")),
+        Region:  jsii.String(os.Getenv("CDK_DEFAULT_REGION")),
+      },
+    },
+ )
 
-  stack := app.NewStack("swarm-example-eventbridge")
-  stack.NewEventBus()
+  broker := eventbridge.NewBroker(stack, jsii.String("Broker"), nil)
+  broker.NewEventBus(nil)
 
-  stack.NewSink(
+  broker.NewSink(
     &eventbridge.SinkProps{
       Source: []string{"swarm-example-eventbridge"},
       Lambda: &scud.FunctionGoProps{

diff --git a/broker/eventbridge/awscdk.go b/broker/eventbridge/awscdk.go
@@ -9,7 +9,6 @@
 package eventbridge
 
 import (
-	"os"
 	"strconv"
 
 	"github.com/aws/aws-cdk-go/awscdk/v2"
@@ -94,117 +93,56 @@ func NewSink(scope constructs.Construct, id *string, props *SinkProps) *Sink {
 
 //------------------------------------------------------------------------------
 //
-// AWS CDK Stack Construct
+// AWS CDK Broker Construct
 //
 //------------------------------------------------------------------------------
 
-type ServerlessStackProps struct {
-	*awscdk.StackProps
-	Version string
-	System  string
+type BrokerProps struct {
+	System string
 }
 
-type ServerlessStack struct {
-	awscdk.Stack
-	acc int
+type Broker struct {
+	constructs.Construct
 	Bus awsevents.IEventBus
+	acc int
 }
 
-func NewServerlessStack(app awscdk.App, id *string, props *ServerlessStackProps) *ServerlessStack {
-	sid := *id
-	if props.Version != "" {
-		sid = sid + "-" + props.Version
-	}
-
-	stack := &ServerlessStack{
-		Stack: awscdk.NewStack(app, jsii.String(sid), props.StackProps),
-	}
+func NewBroker(scope constructs.Construct, id *string, props *BrokerProps) *Broker {
+	broker := &Broker{Construct: constructs.NewConstruct(scope, id)}
 
-	return stack
+	return broker
 }
 
-func (stack *ServerlessStack) NewEventBus(eventBusName ...string) awsevents.IEventBus {
-	name := awscdk.Aws_STACK_NAME()
-	if len(eventBusName) > 0 {
-		name = &eventBusName[0]
+func (broker *Broker) NewEventBus(props *awsevents.EventBusProps) awsevents.IEventBus {
+	if props == nil {
+		props = &awsevents.EventBusProps{}
 	}
 
-	stack.Bus = awsevents.NewEventBus(stack.Stack, jsii.String("Bus"),
-		&awsevents.EventBusProps{EventBusName: name},
-	)
-
-	return stack.Bus
-}
-
-func (stack *ServerlessStack) AddEventBus(eventBusName string) awsevents.IEventBus {
-	stack.Bus = awsevents.EventBus_FromEventBusName(stack.Stack, jsii.String("Bus"), jsii.String(eventBusName))
-
-	return stack.Bus
-}
-
-func (stack *ServerlessStack) NewSink(props *SinkProps) *Sink {
-	if stack.Bus == nil {
-		panic("EventBus is not defined.")
+	if props.EventBusName == nil {
+		props.EventBusName = awscdk.Aws_STACK_NAME()
 	}
 
-	props.System = stack.Bus
+	broker.Bus = awsevents.NewEventBus(broker.Construct, jsii.String("Bus"), props)
 
-	stack.acc++
-	name := "Sink" + strconv.Itoa(stack.acc)
-	sink := NewSink(stack.Stack, jsii.String(name), props)
-
-	return sink
+	return broker.Bus
 }
 
-//------------------------------------------------------------------------------
-//
-// AWS CDK App Construct
-//
-//------------------------------------------------------------------------------
+func (broker *Broker) AddEventBus(eventBusName string) awsevents.IEventBus {
+	broker.Bus = awsevents.EventBus_FromEventBusName(broker.Construct, jsii.String("Bus"), jsii.String(eventBusName))
 
-type ServerlessApp struct {
-	awscdk.App
+	return broker.Bus
 }
 
-func NewServerlessApp() *ServerlessApp {
-	app := awscdk.NewApp(nil)
-	return &ServerlessApp{App: app}
-}
-
-func (app *ServerlessApp) NewStack(name string, props ...*awscdk.StackProps) *ServerlessStack {
-	config := &awscdk.StackProps{
-		Env: &awscdk.Environment{
-			Account: jsii.String(os.Getenv("CDK_DEFAULT_ACCOUNT")),
-			Region:  jsii.String(os.Getenv("CDK_DEFAULT_REGION")),
-		},
-	}
-
-	if len(props) == 1 {
-		config = props[0]
+func (broker *Broker) NewSink(props *SinkProps) *Sink {
+	if broker.Bus == nil {
+		panic("EventBus is not defined.")
 	}
 
-	return NewServerlessStack(app.App, jsii.String(name), &ServerlessStackProps{
-		StackProps: config,
-		Version:    FromContextVsn(app),
-		System:     name,
-	})
-}
-
-func FromContext(app awscdk.App, key string) string {
-	val := app.Node().TryGetContext(jsii.String(key))
-	switch v := val.(type) {
-	case string:
-		return v
-	default:
-		return ""
-	}
-}
+	props.System = broker.Bus
 
-func FromContextVsn(app awscdk.App) string {
-	vsn := FromContext(app, "vsn")
-	if vsn == "" {
-		return "latest"
-	}
+	broker.acc++
+	name := "Sink" + strconv.Itoa(broker.acc)
+	sink := NewSink(broker.Construct, jsii.String(name), props)
 
-	return vsn
+	return sink
 }
diff --git a/broker/eventbridge/awscdk_test.go b/broker/eventbridge/awscdk_test.go
@@ -11,18 +11,21 @@ package eventbridge_test
 import (
 	"testing"
 
+	"github.com/aws/aws-cdk-go/awscdk/v2"
 	"github.com/aws/aws-cdk-go/awscdk/v2/assertions"
 	"github.com/aws/jsii-runtime-go"
 	"github.com/fogfish/scud"
 	"github.com/fogfish/swarm/broker/eventbridge"
 )
 
 func TestEventBridgeCDK(t *testing.T) {
-	app := eventbridge.NewServerlessApp()
-	stack := app.NewStack("swarm-example-eventbridge", nil)
-	stack.NewEventBus()
+	app := awscdk.NewApp(nil)
+	stack := awscdk.NewStack(app, jsii.String("text"), &awscdk.StackProps{})
 
-	stack.NewSink(
+	broker := eventbridge.NewBroker(stack, jsii.String("Test"), nil)
+	broker.NewEventBus(nil)
+
+	broker.NewSink(
 		&eventbridge.SinkProps{
 			Source: []string{"swarm-example-eventbridge"},
 			Lambda: &scud.FunctionGoProps{
@@ -40,7 +43,7 @@ func TestEventBridgeCDK(t *testing.T) {
 		jsii.String("Custom::LogRetention"):  jsii.Number(1),
 	}
 
-	template := assertions.Template_FromStack(stack.Stack, nil)
+	template := assertions.Template_FromStack(stack, nil)
 	for key, val := range require {
 		template.ResourceCountIs(key, val)
 	}