Update setLogger Authorization header filtering logic

CHANGELOG.md

@@ -5,6 +5,7 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+- Update setLogger Authorization header filtering logic. [#111](https://github.com/xmidt-org/bascule/pull/111)
 
 ## [v0.10.1]
 - Added raw parsers for bearer acquirer. [#110](https://github.com/xmidt-org/bascule/pull/110)

basculehttp/log.go

@@ -51,20 +51,27 @@ func getZapLogger(f func(context.Context) *zap.Logger) func(context.Context) log
 	}
 }
 
+func sanitizeHeaders(headers http.Header) (filtered http.Header) {
+	filtered = headers.Clone()
+	if authHeader := filtered.Get("Authorization"); authHeader != "" {
+		filtered.Del("Authorization")
+		parts := strings.Split(authHeader, " ")
+		if len(parts) == 2 {
+			filtered.Set("Authorization-Type", parts[0])
+		}
+	}
+	return
+}
+
 // SetLogger creates an alice constructor that sets up a zap logger that can be
 // used for all logging related to the current request.  The logger is added to
 // the request's context.
 func SetLogger(logger *zap.Logger) alice.Constructor {
 	return func(delegate http.Handler) http.Handler {
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			logHeader := r.Header.Clone()
-			if str := logHeader.Get("Authorization"); str != "" {
-				logHeader.Del("Authorization")
-				logHeader.Set("Authorization-Type", strings.Split(str, " ")[0])
-			}
 			r = r.WithContext(sallust.With(r.Context(),
 				logger.With(
-					zap.Reflect("requestHeaders", logHeader), //lgtm [go/clear-text-logging]
+					zap.Reflect("requestHeaders", sanitizeHeaders(r.Header)), //lgtm [go/clear-text-logging]
 					zap.String("requestURL", r.URL.EscapedPath()),
 					zap.String("method", r.Method))))
 			delegate.ServeHTTP(w, r)

basculehttp/log_test.go

@@ -19,6 +19,7 @@ package basculehttp
 
 import (
 	"context"
+	"net/http"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -36,3 +37,36 @@ func TestGetZapLogger(t *testing.T) {
 		result.Log("msg", "testing", "error", "nope", "level", "debug")
 	})
 }
+
+func TestSanitizeHeaders(t *testing.T) {
+	testCases := []struct {
+		Description string
+		Input       http.Header
+		Expected    http.Header
+	}{
+		{
+			Description: "Filtered",
+			Input:       http.Header{"Authorization": []string{"Basic xyz"}, "HeaderA": []string{"x"}},
+			Expected:    http.Header{"HeaderA": []string{"x"}, "Authorization-Type": []string{"Basic"}},
+		},
+		{
+			Description: "Handled human error",
+			Input:       http.Header{"Authorization": []string{"BasicXYZ"}, "HeaderB": []string{"y"}},
+			Expected:    http.Header{"HeaderB": []string{"y"}},
+		},
+		{
+			Description: "Not a perfect system",
+			Input:       http.Header{"Authorization": []string{"MySecret IWantToLeakIt"}},
+			Expected:    http.Header{"Authorization-Type": []string{"MySecret"}},
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.Description, func(t *testing.T) {
+			assert := assert.New(t)
+			actual := sanitizeHeaders(tc.Input)
+			assert.Equal(tc.Expected, actual)
+		})
+
+	}
+}