From 0c30acf038d226910c2530c9640588c069ff34fe Mon Sep 17 00:00:00 2001
From: Rafael Bonin <rafabonin04@gmail.com>
Date: Thu, 25 Jul 2024 11:24:47 -0300
Subject: [PATCH] Adds v0 of namedHandelers. This can be improved in the future

---
 pkg/events/handler.go           | 12 ++++++-----
 pkg/events/namedHandler.go      | 35 ++++++++++++++++++++++++++++++++
 pkg/events/rabbitmq/consumer.go | 36 +++++++++++++++++++++++++++++++--
 3 files changed, 76 insertions(+), 7 deletions(-)
 create mode 100644 pkg/events/namedHandler.go

diff --git a/pkg/events/handler.go b/pkg/events/handler.go
index b8b697d..daf7891 100644
--- a/pkg/events/handler.go
+++ b/pkg/events/handler.go
@@ -39,12 +39,14 @@ type Handler interface {
 /*
 MatchTopicAndFormatsMessage matches the topic and formats the message.
 
+**This is deprecated and should not be used.**
+
 It takes the following parameters:
-   - ctx: the context.Context object for the function.
-   - decoder: the thunderEvents.EventDecoder object for decoding the message.
-   - referenceTopic: the reference topic string for matching.
-   - topic: the topic string to match against the reference topic.
-   - message: the message object to be formatted.
+  - ctx: the context.Context object for the function.
+  - decoder: the thunderEvents.EventDecoder object for decoding the message.
+  - referenceTopic: the reference topic string for matching.
+  - topic: the topic string to match against the reference topic.
+  - message: the message object to be formatted.
 
 It returns a pointer to the formatted message object and any error encountered.
 if the match fails, nil is returned.
diff --git a/pkg/events/namedHandler.go b/pkg/events/namedHandler.go
new file mode 100644
index 0000000..ab3719c
--- /dev/null
+++ b/pkg/events/namedHandler.go
@@ -0,0 +1,35 @@
+package events
+
+import "go.uber.org/fx"
+
+// NamedHandler is a handler that has a queue name associated with it.
+type NamedHandler interface {
+	QueuePosfix() string
+	Handler
+}
+
+type namedHandler struct {
+	Handler
+	queuePosfix string
+}
+
+func (n *namedHandler) QueuePosfix() string {
+	return n.queuePosfix
+}
+
+// NewNamedHandlerFromHandler creates a new NamedHandler from a Handler.
+func NewNamedHandlerFromHandler(handler Handler, queuePosfix string) NamedHandler {
+	return &namedHandler{
+		Handler:     handler,
+		queuePosfix: queuePosfix,
+	}
+}
+
+// FxAnnotateNamedHandler provides a named handler with group tags.
+// This is used to provide named handlers with the group tag `group:"named_handlers"`.
+// It's not a type safe function, so it's up to the caller to provide the correct type.
+func FxAnnotateNamedHandler(namedHandlerFunc interface{}) fx.Option {
+	return fx.Provide(
+		fx.Annotate(namedHandlerFunc, fx.As(new(NamedHandler)), fx.ResultTags(`group:"named_handlers"`)),
+	)
+}
diff --git a/pkg/events/rabbitmq/consumer.go b/pkg/events/rabbitmq/consumer.go
index 0b8abe6..95059ab 100644
--- a/pkg/events/rabbitmq/consumer.go
+++ b/pkg/events/rabbitmq/consumer.go
@@ -11,8 +11,28 @@ import (
 	"go.uber.org/fx"
 )
 
-func NewRabbitMQConsumer(logger *zerolog.Logger, opts ...rabbitmq.RabbitmqConfigOption) (events.EventConsumer, error) {
-	return consumer.NewConsumer(amqp091.Config{}, logger, opts...)
+type namedHandlerParams struct {
+	fx.In
+	NamedHandlers []events.NamedHandler `group:"named_handlers"`
+}
+
+func registerNamedConsumers(lc fx.Lifecycle, s fx.Shutdowner, logger *zerolog.Logger, params namedHandlerParams) {
+	for _, namedHandler := range params.NamedHandlers {
+		registerNamedConsumer(lc, s, logger, namedHandler)
+	}
+}
+
+func registerNamedConsumer(lc fx.Lifecycle, s fx.Shutdowner, logger *zerolog.Logger, namedHandler events.NamedHandler) {
+	consumer, err := NewRabbitMQConsumer(logger, WithQueueNamePosfix(namedHandler.QueuePosfix()))
+	if err != nil {
+		logger.Error().Err(err).Msg("failed to create consumer")
+		err = s.Shutdown()
+		if err != nil {
+			logger.Error().Err(err).Msg("failed to shutdown")
+		}
+	}
+
+	registerProvidedConsumer(lc, s, logger, namedHandler, consumer)
 }
 
 func registerConsumer(lc fx.Lifecycle, s fx.Shutdowner, logger *zerolog.Logger, handler events.Handler) {
@@ -90,6 +110,10 @@ func registerProvidedConsumer(lc fx.Lifecycle, s fx.Shutdowner, logger *zerolog.
 	)
 }
 
+func NewRabbitMQConsumer(logger *zerolog.Logger, opts ...rabbitmq.RabbitmqConfigOption) (events.EventConsumer, error) {
+	return consumer.NewConsumer(amqp091.Config{}, logger, opts...)
+}
+
 // A module that provides a RabbitMQ consumer.
 // The consumer will be automatically started and stopped gracefully.
 // The consumer will subscribe to the provided topics.
@@ -103,3 +127,11 @@ var InvokeConsumer = fx.Invoke(
 var InvokeProvidedConsumer = fx.Invoke(
 	registerProvidedConsumer,
 )
+
+var InvokeNamedConsumers = fx.Invoke(
+	registerNamedConsumers,
+)
+
+var InvokeNamedConsumer = fx.Invoke(
+	registerNamedConsumer,
+)