From dde69a5e4aef7862ba35d7ae03302aad81815f5c Mon Sep 17 00:00:00 2001
From: Evgeniy Scherbina <evgeniy.shcherbina.es@gmail.com>
Date: Mon, 6 Nov 2023 11:18:12 -0500
Subject: [PATCH] Improve logging (#58)

---
 service/cachemdw/caching_middleware.go   | 29 ++++++++++++++++++++----
 service/cachemdw/is_cached_middleware.go |  6 +----
 service/middleware.go                    | 18 +--------------
 3 files changed, 26 insertions(+), 27 deletions(-)

diff --git a/service/cachemdw/caching_middleware.go b/service/cachemdw/caching_middleware.go
index 177bb6b..087daf3 100644
--- a/service/cachemdw/caching_middleware.go
+++ b/service/cachemdw/caching_middleware.go
@@ -1,9 +1,12 @@
 package cachemdw
 
 import (
+	"bytes"
+	"io"
 	"net/http"
 
 	"github.com/kava-labs/kava-proxy-service/decode"
+	"github.com/kava-labs/kava-proxy-service/logging"
 )
 
 // CachingMiddleware returns kava-proxy-service compatible middleware which works in the following way:
@@ -35,11 +38,7 @@ func (c *ServiceCache) CachingMiddleware(
 		req := r.Context().Value(c.decodedRequestContextKey)
 		decodedReq, ok := (req).(*decode.EVMRPCRequestEnvelope)
 		if !ok {
-			c.Logger.Error().
-				Str("method", r.Method).
-				Str("url", r.URL.String()).
-				Str("host", r.Host).
-				Msg("can't cast request to *EVMRPCRequestEnvelope type")
+			LogCannotCastRequestError(c.ServiceLogger, r)
 
 			next.ServeHTTP(w, r)
 			return
@@ -67,6 +66,26 @@ func (c *ServiceCache) CachingMiddleware(
 	}
 }
 
+func LogCannotCastRequestError(logger *logging.ServiceLogger, r *http.Request) {
+	var bodyCopy bytes.Buffer
+	tee := io.TeeReader(r.Body, &bodyCopy)
+	// read all body from reader into bodyBytes, and copy into bodyCopy
+	bodyBytes, err := io.ReadAll(tee)
+	if err != nil {
+		logger.Error().Err(err).Msg("can't read lrw.body")
+	}
+
+	// replace empty body reader with fresh copy
+	r.Body = io.NopCloser(&bodyCopy)
+
+	logger.Error().
+		Str("method", r.Method).
+		Str("url", r.URL.String()).
+		Str("host", r.Host).
+		Str("body", string(bodyBytes)).
+		Msg("can't cast request to *EVMRPCRequestEnvelope type")
+}
+
 // getHeadersToCache gets header map which has to be cached along with EVM JSON-RPC response
 func getHeadersToCache(w http.ResponseWriter, whitelistedHeaders []string) map[string]string {
 	headersToCache := make(map[string]string, 0)
diff --git a/service/cachemdw/is_cached_middleware.go b/service/cachemdw/is_cached_middleware.go
index 483aa11..e41b4c9 100644
--- a/service/cachemdw/is_cached_middleware.go
+++ b/service/cachemdw/is_cached_middleware.go
@@ -47,11 +47,7 @@ func (c *ServiceCache) IsCachedMiddleware(
 		req := r.Context().Value(c.decodedRequestContextKey)
 		decodedReq, ok := (req).(*decode.EVMRPCRequestEnvelope)
 		if !ok {
-			c.Logger.Error().
-				Str("method", r.Method).
-				Str("url", r.URL.String()).
-				Str("host", r.Host).
-				Msg("can't cast request to *EVMRPCRequestEnvelope type")
+			LogCannotCastRequestError(c.ServiceLogger, r)
 
 			next.ServeHTTP(w, r.WithContext(uncachedContext))
 			return
diff --git a/service/middleware.go b/service/middleware.go
index 28da241..4251074 100644
--- a/service/middleware.go
+++ b/service/middleware.go
@@ -157,23 +157,7 @@ func createProxyRequestMiddleware(next http.Handler, config config.Config, servi
 			req := r.Context().Value(DecodedRequestContextKey)
 			decodedReq, ok := (req).(*decode.EVMRPCRequestEnvelope)
 			if !ok {
-				var bodyCopy bytes.Buffer
-				tee := io.TeeReader(r.Body, &bodyCopy)
-				// read all body from reader into bodyBytes, and copy into bodyCopy
-				bodyBytes, err := io.ReadAll(tee)
-				if err != nil {
-					serviceLogger.Error().Err(err).Msg("can't read lrw.body")
-				}
-
-				// replace empty body reader with fresh copy
-				r.Body = io.NopCloser(&bodyCopy)
-
-				serviceLogger.Logger.Error().
-					Str("method", r.Method).
-					Str("url", r.URL.String()).
-					Str("host", r.Host).
-					Str("body", string(bodyBytes)).
-					Msg("can't cast request to *EVMRPCRequestEnvelope type")
+				cachemdw.LogCannotCastRequestError(serviceLogger, r)
 
 				// if we can't get decoded request then assign it empty structure to avoid panics
 				decodedReq = new(decode.EVMRPCRequestEnvelope)