add option status code log from origin (#4)

* add status-code log

Signed-off-by: taniwa <taniwa@yahoo-corp.jp>

* update

Signed-off-by: taniwa <taniwa@yahoo-corp.jp>

* add option for origin log

Signed-off-by: taniwa <taniwa@yahoo-corp.jp>

* update

Signed-off-by: taniwa <taniwa@yahoo-corp.jp>

* fix

Signed-off-by: taniwa <taniwa@yahoo-corp.jp>

* add handler_test

Signed-off-by: taniwa <taniwa@yahoo-corp.jp>

Signed-off-by: taniwa <taniwa@yahoo-corp.jp>

Author: t4niwa

config/config.go

@@ -154,6 +154,9 @@ type Proxy struct {
 
 	// Transport exposes http.Transport parameters
 	Transport Transport `yaml:"transport,omitempty"`
+
+	// OriginLog represents log configuration from origin
+	OriginLog OriginLog `yaml:"originLog"`
 }
 
 // Authorization represents the detail authorization configuration.
@@ -287,6 +290,17 @@ type Transport struct {
 	ForceAttemptHTTP2      bool          `yaml:"forceAttemptHTTP2,omitempty"`
 }
 
+// OriginLog represents log configuration from origin
+type OriginLog struct {
+	StatusCode StatusCode `yaml:"statusCode"`
+}
+
+// StatusCode represents statuscode log configuration
+type StatusCode struct {
+	Enable  bool  `yaml:"enable"`
+	Exclude []int `yaml:"exclude"`
+}
+
 // New returns the decoded configuration YAML file as *Config struct. Returns non-nil error if any.
 func New(path string) (*Config, error) {
 	f, err := os.OpenFile(path, os.O_RDONLY, 0o600)

config/config_test.go

@@ -127,6 +127,12 @@ func TestNew(t *testing.T) {
 						ReadBufferSize:         0,
 						ForceAttemptHTTP2:      true,
 					},
+					OriginLog: OriginLog{
+						StatusCode: StatusCode{
+							Enable:  true,
+							Exclude: []int{200},
+						},
+					},
 				},
 				Authorization: Authorization{
 					PublicKey: PublicKey{

handler/handler.go

@@ -45,6 +45,19 @@ func New(cfg config.Proxy, bp httputil.BufferPool, prov service.Authorizationd)
 
 	host := fmt.Sprintf("%s:%d", cfg.Host, cfg.Port)
 
+	var modifyResponse func(res *http.Response) error = nil
+	if cfg.OriginLog.StatusCode.Enable {
+		modifyResponse = func(res *http.Response) error {
+			for _, statusCode := range cfg.OriginLog.StatusCode.Exclude {
+				if statusCode == res.StatusCode {
+					return nil
+				}
+			}
+			glg.Infof("Origin request: %s %s, Response: status code: %d", res.Request.Method, res.Request.URL, res.StatusCode)
+			return nil
+		}
+	}
+
 	return &httputil.ReverseProxy{
 		BufferPool: bp,
 		Director: func(r *http.Request) {
@@ -71,6 +84,7 @@ func New(cfg config.Proxy, bp httputil.BufferPool, prov service.Authorizationd)
 
 			*r = *req
 		},
+		ModifyResponse: modifyResponse,
 		Transport: &transport{
 			prov:         prov,
 			RoundTripper: transportFromCfg(cfg.Transport),

handler/handler_test.go

@@ -534,6 +534,25 @@ func TestNew(t *testing.T) {
 				return nil
 			},
 		},
+		{
+			name: "check originlog is used",
+			args: args{
+				cfg: config.Proxy{
+					OriginLog: config.OriginLog{
+						StatusCode: config.StatusCode{
+							Enable:  true,
+							Exclude: []int{},
+						},
+					},
+				},
+			},
+			checkFunc: func(h http.Handler) error {
+				if h.(*httputil.ReverseProxy).ModifyResponse == nil {
+					return errors.Errorf("unexpected ModifyResponse")
+				}
+				return nil
+			},
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {

test/data/example_config.yaml

@@ -44,6 +44,11 @@ proxy:
     writeBufferSize: 0
     readBufferSize: 0
     forceAttemptHTTP2: true
+  originLog:
+    statusCode:
+      enable: true
+      exclude:
+        - 200
 authorization:
   athenzDomains:
   - provider-domain1