Echo v4 integration

_integrations/nrecho/v4/example/main.go

@@ -0,0 +1,58 @@
+package main
+
+import (
+	"fmt"
+	"net/http"
+	"os"
+
+	"github.com/labstack/echo/v4"
+	"github.com/labstack/echo/v4/middleware"
+	"github.com/newrelic/go-agent"
+	"github.com/newrelic/go-agent/_integrations/nrecho/v4"
+)
+
+func mustGetEnv(key string) string {
+	if val := os.Getenv(key); "" != val {
+		return val
+	}
+	panic(fmt.Sprintf("environment variable %s unset", key))
+}
+
+func getUser(c echo.Context) error {
+	id := c.Param("id")
+
+	if txn := nrecho.FromContext(c); nil != txn {
+		txn.AddAttribute("userId", id)
+	}
+
+	return c.String(http.StatusOK, id)
+}
+
+func main() {
+	cfg := newrelic.NewConfig("Echo App", mustGetEnv("NEW_RELIC_LICENSE_KEY"))
+	cfg.Logger = newrelic.NewDebugLogger(os.Stdout)
+	app, err := newrelic.NewApplication(cfg)
+	if nil != err {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+
+	// Echo instance
+	e := echo.New()
+
+	// The New Relic Middleware should be the first middleware registered
+	e.Use(nrecho.Middleware(app))
+
+	// Routes
+	e.GET("/home", func(c echo.Context) error {
+		return c.String(http.StatusOK, "Hello, World!")
+	})
+
+	// Groups
+	g := e.Group("/user")
+	g.Use(middleware.Gzip())
+	g.GET("/:id", getUser)
+
+	// Start server
+	e.Start(":8000")
+}

_integrations/nrecho/v4/nrecho.go

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+// Package nrecho introduces to support for the echo framework.
+//
+// Example: https://github.com/newrelic/go-agent/tree/master/_integrations/nrecho/v4/example/main.go
+package nrecho
+
+import (
+	"net/http"
+	"reflect"
+
+	"github.com/labstack/echo/v4"
+	newrelic "github.com/newrelic/go-agent"
+	"github.com/newrelic/go-agent/internal"
+)
+
+func init() { internal.TrackUsage("integration", "framework", "echo", "v4") }
+
+// FromContext returns the Transaction from the context if present, and nil
+// otherwise.
+func FromContext(c echo.Context) newrelic.Transaction {
+	return newrelic.FromContext(c.Request().Context())
+}
+
+func handlerPointer(handler echo.HandlerFunc) uintptr {
+	return reflect.ValueOf(handler).Pointer()
+}
+
+func transactionName(c echo.Context) string {
+	ptr := handlerPointer(c.Handler())
+	if ptr == handlerPointer(echo.NotFoundHandler) {
+		return "NotFoundHandler"
+	}
+	if ptr == handlerPointer(echo.MethodNotAllowedHandler) {
+		return "MethodNotAllowedHandler"
+	}
+	return c.Path()
+}
+
+// Middleware creates Echo middleware that instruments requests.
+//
+//  e := echo.New()
+//  e.Use(nrecho.Middleware(app))
+//
+func Middleware(app newrelic.Application) func(echo.HandlerFunc) echo.HandlerFunc {
+
+	if nil == app {
+		return func(next echo.HandlerFunc) echo.HandlerFunc {
+			return next
+		}
+	}
+
+	return func(next echo.HandlerFunc) echo.HandlerFunc {
+		return func(c echo.Context) (err error) {
+			rw := c.Response().Writer
+			txn := app.StartTransaction(transactionName(c), rw, c.Request())
+			defer txn.End()
+
+			c.Response().Writer = txn
+
+			// Add txn to c.Request().Context()
+			c.SetRequest(c.Request().WithContext(newrelic.NewContext(c.Request().Context(), txn)))
+
+			err = next(c)
+
+			// Record the response code. The response headers are not captured
+			// in this case because they are set after this middleware returns.
+			// Designed to mimic the logic in echo.DefaultHTTPErrorHandler.
+			if nil != err && !c.Response().Committed {
+
+				txn.SetWebResponse(nil)
+				c.Response().Writer = rw
+
+				if httperr, ok := err.(*echo.HTTPError); ok {
+					txn.WriteHeader(httperr.Code)
+				} else {
+					txn.WriteHeader(http.StatusInternalServerError)
+				}
+			}
+
+			return
+		}
+	}
+}