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Diffstat (limited to 'vendor/k8s.io/apiserver/pkg/server/httplog/log.go')
-rw-r--r--vendor/k8s.io/apiserver/pkg/server/httplog/log.go225
1 files changed, 225 insertions, 0 deletions
diff --git a/vendor/k8s.io/apiserver/pkg/server/httplog/log.go b/vendor/k8s.io/apiserver/pkg/server/httplog/log.go
new file mode 100644
index 000000000..4a4894cee
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+++ b/vendor/k8s.io/apiserver/pkg/server/httplog/log.go
@@ -0,0 +1,225 @@
+/*
+Copyright 2014 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package httplog
+
+import (
+ "bufio"
+ "fmt"
+ "net"
+ "net/http"
+ "runtime"
+ "time"
+
+ "github.com/golang/glog"
+)
+
+// Handler wraps all HTTP calls to delegate with nice logging.
+// delegate may use LogOf(w).Addf(...) to write additional info to
+// the per-request log message.
+//
+// Intended to wrap calls to your ServeMux.
+func Handler(delegate http.Handler, pred StacktracePred) http.Handler {
+ return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+ defer NewLogged(req, &w).StacktraceWhen(pred).Log()
+ delegate.ServeHTTP(w, req)
+ })
+}
+
+// StacktracePred returns true if a stacktrace should be logged for this status.
+type StacktracePred func(httpStatus int) (logStacktrace bool)
+
+type logger interface {
+ Addf(format string, data ...interface{})
+}
+
+// Add a layer on top of ResponseWriter, so we can track latency and error
+// message sources.
+//
+// TODO now that we're using go-restful, we shouldn't need to be wrapping
+// the http.ResponseWriter. We can recover panics from go-restful, and
+// the logging value is questionable.
+type respLogger struct {
+ hijacked bool
+ statusRecorded bool
+ status int
+ statusStack string
+ addedInfo string
+ startTime time.Time
+
+ captureErrorOutput bool
+
+ req *http.Request
+ w http.ResponseWriter
+
+ logStacktracePred StacktracePred
+}
+
+// Simple logger that logs immediately when Addf is called
+type passthroughLogger struct{}
+
+// Addf logs info immediately.
+func (passthroughLogger) Addf(format string, data ...interface{}) {
+ glog.V(2).Info(fmt.Sprintf(format, data...))
+}
+
+// DefaultStacktracePred is the default implementation of StacktracePred.
+func DefaultStacktracePred(status int) bool {
+ return (status < http.StatusOK || status >= http.StatusInternalServerError) && status != http.StatusSwitchingProtocols
+}
+
+// NewLogged turns a normal response writer into a logged response writer.
+//
+// Usage:
+//
+// defer NewLogged(req, &w).StacktraceWhen(StatusIsNot(200, 202)).Log()
+//
+// (Only the call to Log() is deferred, so you can set everything up in one line!)
+//
+// Note that this *changes* your writer, to route response writing actions
+// through the logger.
+//
+// Use LogOf(w).Addf(...) to log something along with the response result.
+func NewLogged(req *http.Request, w *http.ResponseWriter) *respLogger {
+ if _, ok := (*w).(*respLogger); ok {
+ // Don't double-wrap!
+ panic("multiple NewLogged calls!")
+ }
+ rl := &respLogger{
+ startTime: time.Now(),
+ req: req,
+ w: *w,
+ logStacktracePred: DefaultStacktracePred,
+ }
+ *w = rl // hijack caller's writer!
+ return rl
+}
+
+// LogOf returns the logger hiding in w. If there is not an existing logger
+// then a passthroughLogger will be created which will log to stdout immediately
+// when Addf is called.
+func LogOf(req *http.Request, w http.ResponseWriter) logger {
+ if _, exists := w.(*respLogger); !exists {
+ pl := &passthroughLogger{}
+ return pl
+ }
+ if rl, ok := w.(*respLogger); ok {
+ return rl
+ }
+ panic("Unable to find or create the logger!")
+}
+
+// Unlogged returns the original ResponseWriter, or w if it is not our inserted logger.
+func Unlogged(w http.ResponseWriter) http.ResponseWriter {
+ if rl, ok := w.(*respLogger); ok {
+ return rl.w
+ }
+ return w
+}
+
+// StacktraceWhen sets the stacktrace logging predicate, which decides when to log a stacktrace.
+// There's a default, so you don't need to call this unless you don't like the default.
+func (rl *respLogger) StacktraceWhen(pred StacktracePred) *respLogger {
+ rl.logStacktracePred = pred
+ return rl
+}
+
+// StatusIsNot returns a StacktracePred which will cause stacktraces to be logged
+// for any status *not* in the given list.
+func StatusIsNot(statuses ...int) StacktracePred {
+ return func(status int) bool {
+ for _, s := range statuses {
+ if status == s {
+ return false
+ }
+ }
+ return true
+ }
+}
+
+// Addf adds additional data to be logged with this request.
+func (rl *respLogger) Addf(format string, data ...interface{}) {
+ rl.addedInfo += "\n" + fmt.Sprintf(format, data...)
+}
+
+// Log is intended to be called once at the end of your request handler, via defer
+func (rl *respLogger) Log() {
+ latency := time.Since(rl.startTime)
+ if glog.V(2) {
+ if !rl.hijacked {
+ glog.InfoDepth(1, fmt.Sprintf("%s %s: (%v) %v%v%v [%s %s]", rl.req.Method, rl.req.RequestURI, latency, rl.status, rl.statusStack, rl.addedInfo, rl.req.Header["User-Agent"], rl.req.RemoteAddr))
+ } else {
+ glog.InfoDepth(1, fmt.Sprintf("%s %s: (%v) hijacked [%s %s]", rl.req.Method, rl.req.RequestURI, latency, rl.req.Header["User-Agent"], rl.req.RemoteAddr))
+ }
+ }
+}
+
+// Header implements http.ResponseWriter.
+func (rl *respLogger) Header() http.Header {
+ return rl.w.Header()
+}
+
+// Write implements http.ResponseWriter.
+func (rl *respLogger) Write(b []byte) (int, error) {
+ if !rl.statusRecorded {
+ rl.recordStatus(http.StatusOK) // Default if WriteHeader hasn't been called
+ }
+ if rl.captureErrorOutput {
+ rl.Addf("logging error output: %q\n", string(b))
+ }
+ return rl.w.Write(b)
+}
+
+// Flush implements http.Flusher even if the underlying http.Writer doesn't implement it.
+// Flush is used for streaming purposes and allows to flush buffered data to the client.
+func (rl *respLogger) Flush() {
+ if flusher, ok := rl.w.(http.Flusher); ok {
+ flusher.Flush()
+ } else if glog.V(2) {
+ glog.InfoDepth(1, fmt.Sprintf("Unable to convert %+v into http.Flusher", rl.w))
+ }
+}
+
+// WriteHeader implements http.ResponseWriter.
+func (rl *respLogger) WriteHeader(status int) {
+ rl.recordStatus(status)
+ rl.w.WriteHeader(status)
+}
+
+// Hijack implements http.Hijacker.
+func (rl *respLogger) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+ rl.hijacked = true
+ return rl.w.(http.Hijacker).Hijack()
+}
+
+// CloseNotify implements http.CloseNotifier
+func (rl *respLogger) CloseNotify() <-chan bool {
+ return rl.w.(http.CloseNotifier).CloseNotify()
+}
+
+func (rl *respLogger) recordStatus(status int) {
+ rl.status = status
+ rl.statusRecorded = true
+ if rl.logStacktracePred(status) {
+ // Only log stacks for errors
+ stack := make([]byte, 50*1024)
+ stack = stack[:runtime.Stack(stack, false)]
+ rl.statusStack = "\n" + string(stack)
+ rl.captureErrorOutput = true
+ } else {
+ rl.statusStack = ""
+ }
+}