golang微服务框架插件库patron的使用

Patron是一个用于创建微服务的框架，最初由Sotiris Mantzaris创建，现在由Beat Engineering维护。Patron在法语中意为"模板"或"模式"，也有"老板"的意思。

Patron框架概述

Patron框架的入口点是Service。Service使用Components来处理同步和异步请求。框架默认会启动一个HTTP Component，它托管了/debug、/alive、/ready和/metrics端点。其他端点可以作为Routes添加到默认的HTTP Component中。

Patron提供了以下功能的抽象：

• 服务(Service)：协调一切
• 组件(Components)和处理器(Processors)：为服务添加处理功能
  • 异步消息处理(RabbitMQ, Kafka, AWS SQS)
  • 同步处理(HTTP)
  • gRPC支持
• 指标和追踪
• 日志记录

Patron提供了合理的默认值，使使用尽可能简单，最低需要Go 1.24版本。

基础使用示例

下面是一个使用Patron创建简单HTTP服务的基本示例：

package main

import (
	"context"
	"net/http"

	"github.com/beatlabs/patron"
	"github.com/beatlabs/patron/component/http/v2"
	"github.com/beatlabs/patron/log"
)

func main() {
	// 初始化服务
	service, err := patron.New("my-service", "1.0.0")
	if err != nil {
		log.Fatalf("failed to create service: %v", err)
	}

	// 创建HTTP路由
	routes := []http.Route{
		http.NewRoute("/", "GET", handleRoot, true),
		http.NewRoute("/hello", "GET", handleHello, true),
	}

	// 创建HTTP组件
	httpComp, err := http.New(http.DefaultPort()).WithRoutes(routes...).Create()
	if err != nil {
		log.Fatalf("failed to create http component: %v", err)
	}

	// 运行服务
	err = service.WithComponents(httpComp).Run(context.Background())
	if err != nil {
		log.Fatalf("failed to run service: %v", err)
	}
}

// 处理根路径请求
func handleRoot(w http.ResponseWriter, r *http.Request) {
	w.WriteHeader(http.StatusOK)
	_, _ = w.Write([]byte("Welcome to my service!"))
}

// 处理/hello路径请求
func handleHello(w http.ResponseWriter, r *http.Request) {
	w.WriteHeader(http.StatusOK)
	_, _ = w.Write([]byte("Hello, World!"))
}

异步处理示例

Patron也支持异步消息处理，下面是一个使用Kafka的示例：

package main

import (
	"context"
	"fmt"

	"github.com/beatlabs/patron"
	"github.com/beatlabs/patron/component/async"
	"github.com/beatlabs/patron/component/async/kafka"
	"github.com/beatlabs/patron/log"
)

func main() {
	// 初始化服务
	service, err := patron.New("kafka-consumer", "1.0.0")
	if err != nil {
		log.Fatalf("failed to create service: %v", err)
	}

	// 创建Kafka消费者
	kafkaCmp, err := kafka.New("my-group", "my-topic").
		WithBrokers("localhost:9092").
		WithVersion("2.1.0").
		WithProcessor(processMessage).
		Create()
	if err != nil {
		log.Fatalf("failed to create kafka component: %v", err)
	}

	// 运行服务
	err = service.WithComponents(kafkaCmp).Run(context.Background())
	if err != nil {
		log.Fatalf("failed to run service: %v", err)
	}
}

// 处理Kafka消息
func processMessage(msg async.Message) error {
	fmt.Printf("Processing message: %s\n", string(msg.Payload()))
	return nil
}

中间件使用示例

Patron支持为HTTP路由添加中间件：

package main

import (
	"context"
	"net/http"

	"github.com/beatlabs/patron"
	"github.com/beatlabs/patron/component/http/v2"
	"github.com/beatlabs/patron/log"
	"github.com/beatlabs/patron/trace"
	"github.com/opentracing/opentracing-go"
)

func main() {
	// 初始化服务
	service, err := patron.New("middleware-service", "1.0.0")
	if err != nil {
		log.Fatalf("failed to create service: %v", err)
	}

	// 定义中间件
	middleware := []http.MiddlewareFunc{
		traceMiddleware,
		loggingMiddleware,
	}

	// 创建HTTP路由
	routes := []http.Route{
		http.NewRoute("/", "GET", handleRoot, true).WithMiddlewares(middleware...),
	}

	// 创建HTTP组件
	httpComp, err := http.New(http.DefaultPort()).WithRoutes(routes...).Create()
	if err != nil {
		log.Fatalf("failed to create http component: %v", err)
	}

	// 运行服务
	err = service.WithComponents(httpComp).Run(context.Background())
	if err != nil {
		log.Fatalf("failed to run service: %v", err)
	}
}

// 追踪中间件
func traceMiddleware(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		span, _ := trace.ChildSpan(r.Context(), "traceMiddleware", opentracing.StartTime)
		defer span.Finish()
		next.ServeHTTP(w, r)
	})
}

// 日志中间件
func loggingMiddleware(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		log.Infof("Request received: %s %s", r.Method, r.URL.Path)
		next.ServeHTTP(w, r)
	})
}

func handleRoot(w http.ResponseWriter, r *http.Request) {
	w.WriteHeader(http.StatusOK)
	_, _ = w.Write([]byte("Hello with middleware!"))
}

Patron框架为构建微服务提供了全面的支持，包括HTTP服务、异步消息处理、指标收集、追踪和日志记录等功能。通过合理使用这些组件，可以快速构建出稳定可靠的微服务系统。