Merge pull request #54801 from apelisse/fix-broken-truncate

Automatic merge from submit-queue (batch tested with PRs 53190, 54790, 54445, 52607, 54801). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Update `truncateBody` to not truncate with high level

And add a unit-tests to verify that it works properly.

**What this PR does / why we need it**:
Update `truncateBody` so that one can use `V(10)` to read the entire content of a HTTP response.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

**Special notes for your reviewer**:

**Release note**:
```release-note
NONE
```

staging/src/k8s.io/client-go/rest/BUILD

@@ -19,6 +19,7 @@ go_test(
     importpath = "k8s.io/client-go/rest",
     library = ":go_default_library",
     deps = [
+        "//vendor/github.com/golang/glog:go_default_library",
         "//vendor/github.com/google/gofuzz:go_default_library",
         "//vendor/github.com/stretchr/testify/assert:go_default_library",
         "//vendor/k8s.io/api/core/v1:go_default_library",

staging/src/k8s.io/client-go/rest/request.go

@@ -827,6 +827,8 @@ func (r *Request) transformResponse(resp *http.Response, req *http.Request) Resu
 func truncateBody(body string) string {
 	max := 0
 	switch {
+	case bool(glog.V(10)):
+		return body
 	case bool(glog.V(9)):
 		max = 10240
 	case bool(glog.V(8)):

staging/src/k8s.io/client-go/rest/request_test.go

@@ -20,6 +20,7 @@ import (
 	"bytes"
 	"context"
 	"errors"
+	"flag"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -34,6 +35,8 @@ import (
 	"testing"
 	"time"
 
+	"github.com/golang/glog"
+
 	"k8s.io/api/core/v1"
 	apiequality "k8s.io/apimachinery/pkg/api/equality"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
@@ -1696,6 +1699,74 @@ func TestDoContext(t *testing.T) {
 	}
 }
 
+func buildString(length int) string {
+	s := make([]byte, length)
+	for i := range s {
+		s[i] = 'a'
+	}
+	return string(s)
+}
+
+func TestTruncateBody(t *testing.T) {
+	tests := []struct {
+		body  string
+		want  string
+		level string
+	}{
+		// Anything below 8 is completely truncated
+		{
+			body:  "Completely truncated below 8",
+			want:  " [truncated 28 chars]",
+			level: "0",
+		},
+		// Small strings are not truncated by high levels
+		{
+			body:  "Small body never gets truncated",
+			want:  "Small body never gets truncated",
+			level: "10",
+		},
+		{
+			body:  "Small body never gets truncated",
+			want:  "Small body never gets truncated",
+			level: "8",
+		},
+		// Strings are truncated to 1024 if level is less than 9.
+		{
+			body:  buildString(2000),
+			level: "8",
+			want:  fmt.Sprintf("%s [truncated 976 chars]", buildString(1024)),
+		},
+		// Strings are truncated to 10240 if level is 9.
+		{
+			body:  buildString(20000),
+			level: "9",
+			want:  fmt.Sprintf("%s [truncated 9760 chars]", buildString(10240)),
+		},
+		// Strings are not truncated if level is 10 or higher
+		{
+			body:  buildString(20000),
+			level: "10",
+			want:  buildString(20000),
+		},
+		// Strings are not truncated if level is 10 or higher
+		{
+			body:  buildString(20000),
+			level: "11",
+			want:  buildString(20000),
+		},
+	}
+
+	l := flag.Lookup("v").Value.(flag.Getter).Get().(glog.Level)
+	for _, test := range tests {
+		flag.Set("v", test.level)
+		got := truncateBody(test.body)
+		if got != test.want {
+			t.Errorf("truncateBody(%v) = %v, want %v", test.body, got, test.want)
+		}
+	}
+	flag.Set("v", l.String())
+}
+
 func defaultResourcePathWithPrefix(prefix, resource, namespace, name string) string {
 	var path string
 	path = "/api/" + v1.SchemeGroupVersion.Version