Added option to limit response body size on debug log (#99)

And improvements:
  - Refactor `if-else-if-else` chain to use switch(recommended by Effective Go).
  - Add cases `/json`, `/json-invalid`, `/long-text`, `/long-json`

client.go

@@ -85,18 +85,19 @@ type Client struct {
 	JSONMarshal           func(v interface{}) ([]byte, error)
 	JSONUnmarshal         func(data []byte, v interface{}) error
 
-	httpClient       *http.Client
-	setContentLength bool
-	isHTTPMode       bool
-	outputDirectory  string
-	scheme           string
-	proxyURL         *url.URL
-	closeConnection  bool
-	notParseResponse bool
-	beforeRequest    []func(*Client, *Request) error
-	udBeforeRequest  []func(*Client, *Request) error
-	preReqHook       func(*Client, *Request) error
-	afterResponse    []func(*Client, *Response) error
+	httpClient         *http.Client
+	setContentLength   bool
+	isHTTPMode         bool
+	outputDirectory    string
+	scheme             string
+	proxyURL           *url.URL
+	closeConnection    bool
+	notParseResponse   bool
+	debugBodySizeLimit int64
+	beforeRequest      []func(*Client, *Request) error
+	udBeforeRequest    []func(*Client, *Request) error
+	preReqHook         func(*Client, *Request) error
+	afterResponse      []func(*Client, *Response) error
 }
 
 // User type is to hold an username and password information
@@ -372,6 +373,14 @@ func (c *Client) SetDebug(d bool) *Client {
 	return c
 }
 
+// SetDebugBodyLimit sets the maximum size for which the response body will be logged in debug mode.
+//		resty.SetDebugBodyLimit(1000000)
+//
+func (c *Client) SetDebugBodyLimit(sl int64) *Client {
+	c.debugBodySizeLimit = sl
+	return c
+}
+
 // SetDisableWarn method disables the warning message on `go-resty` client.
 // For example: go-resty warns the user when BasicAuth used on HTTP mode.
 //		resty.SetDisableWarn(true)

client_test.go

@@ -5,6 +5,7 @@
 package resty
 
 import (
+	"bytes"
 	"crypto/tls"
 	"errors"
 	"io/ioutil"
@@ -340,6 +341,10 @@ func TestClientOptions(t *testing.T) {
 	SetDebug(true)
 	assertEqual(t, DefaultClient.Debug, true)
 
+	var sl int64 = 1000000
+	SetDebugBodyLimit(sl)
+	assertEqual(t, DefaultClient.debugBodySizeLimit, sl)
+
 	SetAllowGetMethodPayload(true)
 	assertEqual(t, DefaultClient.AllowGetMethodPayload, true)
 
@@ -411,6 +416,42 @@ func TestNewRequest(t *testing.T) {
 	assertNotNil(t, request)
 }
 
+func TestDebugBodySizeLimit(t *testing.T) {
+	ts := createGetServer(t)
+	defer ts.Close()
+
+	var lgr bytes.Buffer
+	c := dc()
+	c.SetDebug(true)
+	c.SetLogger(&lgr)
+	c.SetDebugBodyLimit(30)
+
+	testcases := []struct{ url, want string }{
+		// Text, does not exceed limit.
+		{ts.URL, "TestGet: text response"},
+		// Empty response.
+		{ts.URL + "/no-content", "***** NO CONTENT *****"},
+		// JSON, does not exceed limit.
+		{ts.URL + "/json", "{\n   \"TestGet\": \"JSON response\"\n}"},
+		// Invalid JSON, does not exceed limit.
+		{ts.URL + "/json-invalid", "TestGet: Invalid JSON"},
+		// Text, exceeds limit.
+		{ts.URL + "/long-text", "RESPONSE TOO LARGE"},
+		// JSON, exceeds limit.
+		{ts.URL + "/long-json", "RESPONSE TOO LARGE"},
+	}
+
+	for _, tc := range testcases {
+		_, err := c.R().Get(tc.url)
+		assertError(t, err)
+		debugLog := lgr.String()
+		if !strings.Contains(debugLog, tc.want) {
+			t.Errorf("Expected logs to contain [%v], got [\n%v]", tc.want, debugLog)
+		}
+		lgr.Reset()
+	}
+}
+
 // CustomRoundTripper just for test
 type CustomRoundTripper struct {
 }

default.go

@@ -8,6 +8,7 @@ import (
 	"crypto/tls"
 	"encoding/json"
 	"io"
+	"math"
 	"net/http"
 	"net/http/cookiejar"
 	"net/url"
@@ -25,21 +26,22 @@ func New() *Client {
 	cookieJar, _ := cookiejar.New(&cookiejar.Options{PublicSuffixList: publicsuffix.List})
 
 	c := &Client{
-		HostURL:          "",
-		QueryParam:       url.Values{},
-		FormData:         url.Values{},
-		Header:           http.Header{},
-		UserInfo:         nil,
-		Token:            "",
-		Cookies:          make([]*http.Cookie, 0),
-		Debug:            false,
-		Log:              getLogger(os.Stderr),
-		RetryCount:       0,
-		RetryWaitTime:    defaultWaitTime,
-		RetryMaxWaitTime: defaultMaxWaitTime,
-		JSONMarshal:      json.Marshal,
-		JSONUnmarshal:    json.Unmarshal,
-		httpClient:       &http.Client{Jar: cookieJar},
+		HostURL:            "",
+		QueryParam:         url.Values{},
+		FormData:           url.Values{},
+		Header:             http.Header{},
+		UserInfo:           nil,
+		Token:              "",
+		Cookies:            make([]*http.Cookie, 0),
+		Debug:              false,
+		Log:                getLogger(os.Stderr),
+		RetryCount:         0,
+		RetryWaitTime:      defaultWaitTime,
+		RetryMaxWaitTime:   defaultMaxWaitTime,
+		JSONMarshal:        json.Marshal,
+		JSONUnmarshal:      json.Unmarshal,
+		httpClient:         &http.Client{Jar: cookieJar},
+		debugBodySizeLimit: math.MaxInt32,
 	}
 
 	// Default transport
@@ -158,6 +160,11 @@ func SetDebug(d bool) *Client {
 	return DefaultClient.SetDebug(d)
 }
 
+// SetDebugBodyLimit method sets the response body limit for debug mode. See `Client.SetDebugBodyLimit` for more information.
+func SetDebugBodyLimit(sl int64) *Client {
+	return DefaultClient.SetDebugBodyLimit(sl)
+}
+
 // SetAllowGetMethodPayload method allows the GET method with payload. See `Client.SetAllowGetMethodPayload` for more information.
 func SetAllowGetMethodPayload(a bool) *Client {
 	return DefaultClient.SetAllowGetMethodPayload(a)

middleware.go

@@ -227,7 +227,7 @@ func responseLogger(c *Client, res *Response) error {
 		if res.Request.isSaveResponse {
 			c.Log.Printf("BODY   :\n***** RESPONSE WRITTEN INTO FILE *****")
 		} else {
-			c.Log.Printf("BODY   :\n%v", res.fmtBodyString())
+			c.Log.Printf("BODY   :\n%v", res.fmtBodyString(c.debugBodySizeLimit))
 		}
 		c.Log.Println("----------------------------------------------------------")
 		c.enableLogPrefix()

response.go

@@ -6,6 +6,7 @@ package resty
 
 import (
 	"encoding/json"
+	"fmt"
 	"io"
 	"net/http"
 	"strings"
@@ -119,20 +120,21 @@ func (r *Response) RawBody() io.ReadCloser {
 	return r.RawResponse.Body
 }
 
-func (r *Response) fmtBodyString() string {
-	bodyStr := "***** NO CONTENT *****"
+func (r *Response) fmtBodyString(sl int64) string {
 	if r.body != nil {
+		if int64(len(r.body)) > sl {
+			return fmt.Sprintf("***** RESPONSE TOO LARGE (size - %d) *****", len(r.body))
+		}
 		ct := r.Header().Get(hdrContentTypeKey)
 		if IsJSONType(ct) {
 			out := acquireBuffer()
 			defer releaseBuffer(out)
 			if err := json.Indent(out, r.body, "", "   "); err == nil {
-				bodyStr = string(out.Bytes())
+				return out.String()
 			}
-		} else {
-			bodyStr = r.String()
 		}
+		return r.String()
 	}
 
-	return bodyStr
+	return "***** NO CONTENT *****"
 }

resty_test.go

@@ -1232,19 +1232,33 @@ func createGetServer(t *testing.T) *httptest.Server {
 		t.Logf("Path: %v", r.URL.Path)
 
 		if r.Method == MethodGet {
-			if r.URL.Path == "/" {
+			switch r.URL.Path {
+			case "/":
 				_, _ = w.Write([]byte("TestGet: text response"))
-			} else if r.URL.Path == "/mypage" {
+			case "/no-content":
+				_, _ = w.Write([]byte(""))
+			case "/json":
+				w.Header().Set("Content-Type", "application/json")
+				_, _ = w.Write([]byte(`{"TestGet": "JSON response"}`))
+			case "/json-invalid":
+				w.Header().Set("Content-Type", "application/json")
+				_, _ = w.Write([]byte("TestGet: Invalid JSON"))
+			case "/long-text":
+				_, _ = w.Write([]byte("TestGet: text response with size > 30"))
+			case "/long-json":
+				w.Header().Set("Content-Type", "application/json")
+				_, _ = w.Write([]byte(`{"TestGet": "JSON response with size > 30"}`))
+			case "/mypage":
 				w.WriteHeader(http.StatusBadRequest)
-			} else if r.URL.Path == "/mypage2" {
+			case "/mypage2":
 				_, _ = w.Write([]byte("TestGet: text response from mypage2"))
-			} else if r.URL.Path == "/set-retrycount-test" {
+			case "/set-retrycount-test":
 				attp := atomic.AddInt32(&attempt, 1)
 				if attp <= 3 {
 					time.Sleep(time.Second * 6)
 				}
 				_, _ = w.Write([]byte("TestClientRetry page"))
-			} else if r.URL.Path == "/set-retrywaittime-test" {
+			case "/set-retrywaittime-test":
 				// Returns time.Duration since last request here
 				// or 0 for the very first request
 				if atomic.LoadInt32(&attempt) == 0 {
@@ -1257,20 +1271,19 @@ func createGetServer(t *testing.T) *httptest.Server {
 					_, _ = fmt.Fprintf(w, "%d", uint64(sinceLastRequest))
 				}
 				atomic.AddInt32(&attempt, 1)
-			} else if r.URL.Path == "/set-timeout-test-with-sequence" {
+			case "/set-timeout-test-with-sequence":
 				seq := atomic.AddInt32(&sequence, 1)
 				time.Sleep(time.Second * 2)
 				_, _ = fmt.Fprintf(w, "%d", seq)
-			} else if r.URL.Path == "/set-timeout-test" {
+			case "/set-timeout-test":
 				time.Sleep(time.Second * 6)
 				_, _ = w.Write([]byte("TestClientTimeout page"))
-
-			} else if r.URL.Path == "/my-image.png" {
+			case "/my-image.png":
 				fileBytes, _ := ioutil.ReadFile(getTestDataPath() + "/test-img.png")
 				w.Header().Set("Content-Type", "image/png")
 				w.Header().Set("Content-Length", strconv.Itoa(len(fileBytes)))
 				_, _ = w.Write(fileBytes)
-			} else if r.URL.Path == "/get-method-payload-test" {
+			case "/get-method-payload-test":
 				body, err := ioutil.ReadAll(r.Body)
 				if err != nil {
 					t.Errorf("Error: could not read get body: %s", err.Error())