replace "dep" with "go mod"

A simple "go mod init && go mod tidy && go mod vendor" was enough and
mostly seems to have picked the same revisions of the dependencies as
before. Notable exceptions are klog and gogo/protobuf.

vendor/k8s.io/klog/.travis.yml

@@ -0,0 +1,15 @@
+language: go
+go_import_path: k8s.io/klog
+dist: xenial
+go:
+  - 1.9.x
+  - 1.10.x
+  - 1.11.x
+script:
+  - go get -t -v ./...
+  - diff -u <(echo -n) <(gofmt -d .)
+  - diff -u <(echo -n) <(golint $(go list -e ./...))
+  - go tool vet .
+  - go test -v -race ./...
+install:
+  - go get golang.org/x/lint/golint

vendor/k8s.io/klog/CONTRIBUTING.md

@@ -0,0 +1,22 @@
+# Contributing Guidelines
+
+Welcome to Kubernetes. We are excited about the prospect of you joining our [community](https://github.com/kubernetes/community)! The Kubernetes community abides by the CNCF [code of conduct](code-of-conduct.md). Here is an excerpt:
+
+_As contributors and maintainers of this project, and in the interest of fostering an open and welcoming community, we pledge to respect all people who contribute through reporting issues, posting feature requests, updating documentation, submitting pull requests or patches, and other activities._
+
+## Getting Started
+
+We have full documentation on how to get started contributing here:
+
+- [Contributor License Agreement](https://git.k8s.io/community/CLA.md) Kubernetes projects require that you sign a Contributor License Agreement (CLA) before we can accept your pull requests
+- [Kubernetes Contributor Guide](http://git.k8s.io/community/contributors/guide) - Main contributor documentation, or you can just jump directly to the [contributing section](http://git.k8s.io/community/contributors/guide#contributing)
+- [Contributor Cheat Sheet](https://git.k8s.io/community/contributors/guide/contributor-cheatsheet.md) - Common resources for existing developers
+
+## Mentorship
+
+- [Mentoring Initiatives](https://git.k8s.io/community/mentoring) - We have a diverse set of mentorship programs available that are always looking for volunteers!
+
+## Contact Information
+
+- [Slack](https://kubernetes.slack.com/messages/sig-architecture)
+- [Mailing List](https://groups.google.com/forum/#!forum/kubernetes-sig-architecture)

vendor/k8s.io/klog/OWNERS

@@ -0,0 +1,19 @@
+# See the OWNERS docs at https://go.k8s.io/owners
+reviewers:
+  - jayunit100
+  - hoegaarden
+  - andyxning
+  - neolit123
+  - pohly
+  - yagonobre
+  - vincepri
+  - detiber
+approvers:
+  - dims
+  - thockin
+  - justinsb
+  - tallclair
+  - piosz
+  - brancz
+  - DirectXMan12
+  - lavalamp

vendor/k8s.io/klog/README.md

@@ -0,0 +1,97 @@
+klog
+====
+
+klog is a permanent fork of https://github.com/golang/glog.
+
+## Why was klog created?
+
+The decision to create klog was one that wasn't made lightly, but it was necessary due to some
+drawbacks that are present in [glog](https://github.com/golang/glog). Ultimately, the fork was created due to glog not being under active development; this can be seen in the glog README:
+
+> The code in this repo [...] is not itself under development
+
+This makes us unable to solve many use cases without a fork. The factors that contributed to needing feature development are listed below:
+
+ * `glog` [presents a lot "gotchas"](https://github.com/kubernetes/kubernetes/issues/61006) and introduces challenges in containerized environments, all of which aren't well documented.
+ * `glog` doesn't provide an easy way to test logs, which detracts from the stability of software using it
+ * A long term goal is to implement a logging interface that allows us to add context, change output format, etc.
+ 
+Historical context is available here:
+
+ * https://github.com/kubernetes/kubernetes/issues/61006
+ * https://github.com/kubernetes/kubernetes/issues/70264
+ * https://groups.google.com/forum/#!msg/kubernetes-sig-architecture/wCWiWf3Juzs/hXRVBH90CgAJ
+ * https://groups.google.com/forum/#!msg/kubernetes-dev/7vnijOMhLS0/1oRiNtigBgAJ
+
+----
+
+How to use klog
+===============
+- Replace imports for `github.com/golang/glog` with `k8s.io/klog`
+- Use `klog.InitFlags(nil)` explicitly for initializing global flags as we no longer use `init()` method to register the flags
+- You can now use `log-file` instead of `log-dir` for logging to a single file (See `examples/log_file/usage_log_file.go`)
+- If you want to redirect everything logged using klog somewhere else (say syslog!), you can use `klog.SetOutput()` method and supply a `io.Writer`. (See `examples/set_output/usage_set_output.go`)
+- For more logging conventions (See [Logging Conventions](https://github.com/kubernetes/community/blob/master/contributors/devel/logging.md))
+
+### Coexisting with glog
+This package can be used side by side with glog. [This example](examples/coexist_glog/coexist_glog.go) shows how to initialize and syncronize flags from the global `flag.CommandLine` FlagSet. In addition, the example makes use of stderr as combined output by setting `alsologtostderr` (or `logtostderr`) to `true`.
+
+## Community, discussion, contribution, and support
+
+Learn how to engage with the Kubernetes community on the [community page](http://kubernetes.io/community/).
+
+You can reach the maintainers of this project at:
+
+- [Slack](https://kubernetes.slack.com/messages/sig-architecture)
+- [Mailing List](https://groups.google.com/forum/#!forum/kubernetes-sig-architecture)
+
+### Code of conduct
+
+Participation in the Kubernetes community is governed by the [Kubernetes Code of Conduct](code-of-conduct.md).
+
+----
+
+glog
+====
+
+Leveled execution logs for Go.
+
+This is an efficient pure Go implementation of leveled logs in the
+manner of the open source C++ package
+	https://github.com/google/glog
+
+By binding methods to booleans it is possible to use the log package
+without paying the expense of evaluating the arguments to the log.
+Through the -vmodule flag, the package also provides fine-grained
+control over logging at the file level.
+
+The comment from glog.go introduces the ideas:
+
+	Package glog implements logging analogous to the Google-internal
+	C++ INFO/ERROR/V setup.  It provides functions Info, Warning,
+	Error, Fatal, plus formatting variants such as Infof. It
+	also provides V-style logging controlled by the -v and
+	-vmodule=file=2 flags.
+
+	Basic examples:
+
+		glog.Info("Prepare to repel boarders")
+
+		glog.Fatalf("Initialization failed: %s", err)
+
+	See the documentation for the V function for an explanation
+	of these examples:
+
+		if glog.V(2) {
+			glog.Info("Starting transaction...")
+		}
+
+		glog.V(2).Infoln("Processed", nItems, "elements")
+
+
+The repository contains an open source version of the log package
+used inside Google. The master copy of the source lives inside
+Google, not here. The code in this repo is for export only and is not itself
+under development. Feature requests will be ignored.
+
+Send bug reports to golang-nuts@googlegroups.com.

vendor/k8s.io/klog/RELEASE.md

@@ -0,0 +1,9 @@
+# Release Process
+
+The `klog` is released on an as-needed basis. The process is as follows:
+
+1. An issue is proposing a new release with a changelog since the last release
+1. All [OWNERS](OWNERS) must LGTM this release
+1. An OWNER runs `git tag -s $VERSION` and inserts the changelog and pushes the tag with `git push $VERSION`
+1. The release issue is closed
+1. An announcement email is sent to `kubernetes-dev@googlegroups.com` with the subject `[ANNOUNCE] kubernetes-template-project $VERSION is released`

vendor/k8s.io/klog/SECURITY_CONTACTS

@@ -0,0 +1,20 @@
+# Defined below are the security contacts for this repo.
+#
+# They are the contact point for the Product Security Committee to reach out
+# to for triaging and handling of incoming issues.
+#
+# The below names agree to abide by the
+# [Embargo Policy](https://git.k8s.io/security/private-distributors-list.md#embargo-policy)
+# and will be removed and replaced if they violate that agreement.
+#
+# DO NOT REPORT SECURITY VULNERABILITIES DIRECTLY TO THESE NAMES, FOLLOW THE
+# INSTRUCTIONS AT https://kubernetes.io/security/
+
+dims
+thockin
+justinsb
+tallclair
+piosz
+brancz
+DirectXMan12
+lavalamp

vendor/k8s.io/klog/code-of-conduct.md

@@ -0,0 +1,3 @@
+# Kubernetes Community Code of Conduct
+
+Please refer to our [Kubernetes Community Code of Conduct](https://git.k8s.io/community/code-of-conduct.md)

vendor/k8s.io/klog/klog.go

@@ -43,7 +43,7 @@
 //		Logs are written to standard error instead of to files.
 //	-alsologtostderr=false
 //		Logs are written to standard error as well as to files.
-//	-stderrthreshold=INFO
+//	-stderrthreshold=ERROR
 //		Log events at or above this severity are logged to standard
 //		error as well as to files.
 //	-log_dir=""
@@ -78,6 +78,7 @@ import (
 	"fmt"
 	"io"
 	stdLog "log"
+	"math"
 	"os"
 	"path/filepath"
 	"runtime"
@@ -396,24 +397,43 @@ type flushSyncWriter interface {
 }
 
 func init() {
-	// Default stderrThreshold is INFO.
-	logging.stderrThreshold = infoLog
+	// Default stderrThreshold is ERROR.
+	logging.stderrThreshold = errorLog
 
 	logging.setVState(0, nil, false)
 	go logging.flushDaemon()
 }
 
-// InitFlags is for explicitly initializing the flags
+var initDefaultsOnce sync.Once
+
+// InitFlags is for explicitly initializing the flags.
 func InitFlags(flagset *flag.FlagSet) {
+
+	// Initialize defaults.
+	initDefaultsOnce.Do(func() {
+		logging.logDir = ""
+		logging.logFile = ""
+		logging.logFileMaxSizeMB = 1800
+		logging.toStderr = true
+		logging.alsoToStderr = false
+		logging.skipHeaders = false
+		logging.skipLogHeaders = false
+	})
+
 	if flagset == nil {
 		flagset = flag.CommandLine
 	}
-	flagset.StringVar(&logging.logDir, "log_dir", "", "If non-empty, write log files in this directory")
-	flagset.StringVar(&logging.logFile, "log_file", "", "If non-empty, use this log file")
-	flagset.BoolVar(&logging.toStderr, "logtostderr", true, "log to standard error instead of files")
-	flagset.BoolVar(&logging.alsoToStderr, "alsologtostderr", false, "log to standard error as well as files")
+
+	flagset.StringVar(&logging.logDir, "log_dir", logging.logDir, "If non-empty, write log files in this directory")
+	flagset.StringVar(&logging.logFile, "log_file", logging.logFile, "If non-empty, use this log file")
+	flagset.Uint64Var(&logging.logFileMaxSizeMB, "log_file_max_size", logging.logFileMaxSizeMB,
+		"Defines the maximum size a log file can grow to. Unit is megabytes. "+
+			"If the value is 0, the maximum file size is unlimited.")
+	flagset.BoolVar(&logging.toStderr, "logtostderr", logging.toStderr, "log to standard error instead of files")
+	flagset.BoolVar(&logging.alsoToStderr, "alsologtostderr", logging.alsoToStderr, "log to standard error as well as files")
 	flagset.Var(&logging.verbosity, "v", "number for the log level verbosity")
-	flagset.BoolVar(&logging.skipHeaders, "skip_headers", false, "If true, avoid header prefixes in the log messages")
+	flagset.BoolVar(&logging.skipHeaders, "skip_headers", logging.skipHeaders, "If true, avoid header prefixes in the log messages")
+	flagset.BoolVar(&logging.skipLogHeaders, "skip_log_headers", logging.skipLogHeaders, "If true, avoid headers when opening log files")
 	flagset.Var(&logging.stderrThreshold, "stderrthreshold", "logs at or above this threshold go to stderr")
 	flagset.Var(&logging.vmodule, "vmodule", "comma-separated list of pattern=N settings for file-filtered logging")
 	flagset.Var(&logging.traceLocation, "log_backtrace_at", "when logging hits line file:N, emit a stack trace")
@@ -471,8 +491,15 @@ type loggingT struct {
 	// with the log-dir option.
 	logFile string
 
+	// When logFile is specified, this limiter makes sure the logFile won't exceeds a certain size. When exceeds, the
+	// logFile will be cleaned up. If this value is 0, no size limitation will be applied to logFile.
+	logFileMaxSizeMB uint64
+
 	// If true, do not add the prefix headers, useful when used with SetOutput
 	skipHeaders bool
+
+	// If true, do not add the headers to log files
+	skipLogHeaders bool
 }
 
 // buffer holds a byte Buffer for reuse. The zero value is ready for use.
@@ -739,9 +766,7 @@ func (l *loggingT) output(s severity, buf *buffer, file string, line int, alsoTo
 	}
 	data := buf.Bytes()
 	if l.toStderr {
-		if s >= l.stderrThreshold.get() {
-			os.Stderr.Write(data)
-		}
+		os.Stderr.Write(data)
 	} else {
 		if alsoToStderr || l.alsoToStderr || s >= l.stderrThreshold.get() {
 			os.Stderr.Write(data)
@@ -863,18 +888,33 @@ func (l *loggingT) exit(err error) {
 type syncBuffer struct {
 	logger *loggingT
 	*bufio.Writer
-	file   *os.File
-	sev    severity
-	nbytes uint64 // The number of bytes written to this file
+	file     *os.File
+	sev      severity
+	nbytes   uint64 // The number of bytes written to this file
+	maxbytes uint64 // The max number of bytes this syncBuffer.file can hold before cleaning up.
 }
 
 func (sb *syncBuffer) Sync() error {
 	return sb.file.Sync()
 }
 
+// CalculateMaxSize returns the real max size in bytes after considering the default max size and the flag options.
+func CalculateMaxSize() uint64 {
+	if logging.logFile != "" {
+		if logging.logFileMaxSizeMB == 0 {
+			// If logFileMaxSizeMB is zero, we don't have limitations on the log size.
+			return math.MaxUint64
+		}
+		// Flag logFileMaxSizeMB is in MB for user convenience.
+		return logging.logFileMaxSizeMB * 1024 * 1024
+	}
+	// If "log_file" flag is not specified, the target file (sb.file) will be cleaned up when reaches a fixed size.
+	return MaxSize
+}
+
 func (sb *syncBuffer) Write(p []byte) (n int, err error) {
-	if sb.nbytes+uint64(len(p)) >= MaxSize {
-		if err := sb.rotateFile(time.Now()); err != nil {
+	if sb.nbytes+uint64(len(p)) >= sb.maxbytes {
+		if err := sb.rotateFile(time.Now(), false); err != nil {
 			sb.logger.exit(err)
 		}
 	}
@@ -887,13 +927,15 @@ func (sb *syncBuffer) Write(p []byte) (n int, err error) {
 }
 
 // rotateFile closes the syncBuffer's file and starts a new one.
-func (sb *syncBuffer) rotateFile(now time.Time) error {
+// The startup argument indicates whether this is the initial startup of klog.
+// If startup is true, existing files are opened for appending instead of truncated.
+func (sb *syncBuffer) rotateFile(now time.Time, startup bool) error {
 	if sb.file != nil {
 		sb.Flush()
 		sb.file.Close()
 	}
 	var err error
-	sb.file, _, err = create(severityName[sb.sev], now)
+	sb.file, _, err = create(severityName[sb.sev], now, startup)
 	sb.nbytes = 0
 	if err != nil {
 		return err
@@ -901,6 +943,10 @@ func (sb *syncBuffer) rotateFile(now time.Time) error {
 
 	sb.Writer = bufio.NewWriterSize(sb.file, bufferSize)
 
+	if sb.logger.skipLogHeaders {
+		return nil
+	}
+
 	// Write header.
 	var buf bytes.Buffer
 	fmt.Fprintf(&buf, "Log file created at: %s\n", now.Format("2006/01/02 15:04:05"))
@@ -925,10 +971,11 @@ func (l *loggingT) createFiles(sev severity) error {
 	// has already been created, we can stop.
 	for s := sev; s >= infoLog && l.file[s] == nil; s-- {
 		sb := &syncBuffer{
-			logger: l,
-			sev:    s,
+			logger:   l,
+			sev:      s,
+			maxbytes: CalculateMaxSize(),
 		}
-		if err := sb.rotateFile(now); err != nil {
+		if err := sb.rotateFile(now, true); err != nil {
 			return err
 		}
 		l.file[s] = sb

vendor/k8s.io/klog/klog_file.go

@@ -97,9 +97,11 @@ var onceLogDirs sync.Once
 // contains tag ("INFO", "FATAL", etc.) and t.  If the file is created
 // successfully, create also attempts to update the symlink for that tag, ignoring
 // errors.
-func create(tag string, t time.Time) (f *os.File, filename string, err error) {
+// The startup argument indicates whether this is the initial startup of klog.
+// If startup is true, existing files are opened for appending instead of truncated.
+func create(tag string, t time.Time, startup bool) (f *os.File, filename string, err error) {
 	if logging.logFile != "" {
-		f, err := os.Create(logging.logFile)
+		f, err := openOrCreate(logging.logFile, startup)
 		if err == nil {
 			return f, logging.logFile, nil
 		}
@@ -113,7 +115,7 @@ func create(tag string, t time.Time) (f *os.File, filename string, err error) {
 	var lastErr error
 	for _, dir := range logDirs {
 		fname := filepath.Join(dir, name)
-		f, err := os.Create(fname)
+		f, err := openOrCreate(fname, startup)
 		if err == nil {
 			symlink := filepath.Join(dir, link)
 			os.Remove(symlink)        // ignore err
@@ -124,3 +126,14 @@ func create(tag string, t time.Time) (f *os.File, filename string, err error) {
 	}
 	return nil, "", fmt.Errorf("log: cannot create log: %v", lastErr)
 }
+
+// The startup argument indicates whether this is the initial startup of klog.
+// If startup is true, existing files are opened for appending instead of truncated.
+func openOrCreate(name string, startup bool) (*os.File, error) {
+	if startup {
+		f, err := os.OpenFile(name, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
+		return f, err
+	}
+	f, err := os.Create(name)
+	return f, err
+}