nsq*: log HTTP requests

internal/http_api/api_response.go

@@ -3,12 +3,17 @@ package http_api
 import (
 	"encoding/json"
 	"fmt"
+	"io"
 	"net/http"
 	"strconv"
+	"time"
 
+	"github.com/bitly/nsq/internal/app"
 	"github.com/julienschmidt/httprouter"
 )
 
+type Decorator func(APIHandler) APIHandler
+
 type APIHandler func(http.ResponseWriter, *http.Request, httprouter.Params) (interface{}, error)
 
 type Err struct {
@@ -28,8 +33,24 @@ func acceptVersion(req *http.Request) int {
 	return 0
 }
 
-func NegotiateVersion(f APIHandler) httprouter.Handle {
-	return func(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
+func PlainText(f APIHandler) APIHandler {
+	return func(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {
+		code := 200
+		data, err := f(w, req, ps)
+		if err != nil {
+			code = err.(Err).Code
+			data = err.Error()
+		}
+		response := data.(string)
+		w.Header().Set("Content-Length", strconv.Itoa(len(response)))
+		w.WriteHeader(code)
+		io.WriteString(w, response)
+		return nil, nil
+	}
+}
+
+func NegotiateVersion(f APIHandler) APIHandler {
+	return func(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {
 		data, err := f(w, req, ps)
 		if err != nil {
 			if acceptVersion(req) == 1 {
@@ -38,24 +59,26 @@ func NegotiateVersion(f APIHandler) httprouter.Handle {
 				// this handler always returns 500 for backwards compatibility
 				Respond(w, 500, err.Error(), nil)
 			}
-			return
+			return nil, nil
 		}
 		if acceptVersion(req) == 1 {
 			RespondV1(w, 200, data)
 		} else {
 			Respond(w, 200, "OK", data)
 		}
+		return nil, nil
 	}
 }
 
-func V1(f APIHandler) httprouter.Handle {
-	return func(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
+func V1(f APIHandler) APIHandler {
+	return func(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {
 		data, err := f(w, req, ps)
 		if err != nil {
 			RespondV1(w, err.(Err).Code, err)
-			return
+			return nil, nil
 		}
 		RespondV1(w, 200, data)
+		return nil, nil
 	}
 }
 
@@ -125,3 +148,55 @@ func RespondV1(w http.ResponseWriter, code int, data interface{}) {
 	w.WriteHeader(code)
 	w.Write(response)
 }
+
+func Decorate(f APIHandler, ds ...Decorator) httprouter.Handle {
+	decorated := f
+	for _, decorate := range ds {
+		decorated = decorate(decorated)
+	}
+	return func(w http.ResponseWriter, req *http.Request, ps httprouter.Params) {
+		decorated(w, req, ps)
+	}
+}
+
+func Log(l app.Logger) Decorator {
+	return func(f APIHandler) APIHandler {
+		return func(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {
+			start := time.Now()
+			response, err := f(w, req, ps)
+			elapsed := time.Since(start)
+			status := 200
+			if e, ok := err.(Err); ok {
+				status = e.Code
+			}
+			l.Output(2, fmt.Sprintf("%d %s %s (%s) %s",
+				status, req.Method, req.URL.RequestURI(), req.RemoteAddr, elapsed))
+			return response, err
+		}
+	}
+}
+
+func LogPanicHandler(l app.Logger) func(w http.ResponseWriter, req *http.Request, p interface{}) {
+	return func(w http.ResponseWriter, req *http.Request, p interface{}) {
+		l.Output(2, fmt.Sprintf("ERROR: panic in HTTP handler - %s", p))
+		Decorate(func(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {
+			return nil, Err{500, "INTERNAL_ERROR"}
+		}, Log(l), V1)(w, req, nil)
+	}
+}
+
+func LogNotFoundHandler(l app.Logger) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+		Decorate(func(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {
+			return nil, Err{404, "NOT_FOUND"}
+		}, Log(l), V1)(w, req, nil)
+	})
+}
+
+func LogMethodNotAllowedHandler(l app.Logger) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+		Decorate(func(w http.ResponseWriter, req *http.Request, ps httprouter.Params) (interface{}, error) {
+			return nil, Err{405, "METHOD_NOT_ALLOWED"}
+		}, Log(l), V1)(w, req, nil)
+	})
+}