minio/cmd/http-tracer.go
Harshavardhana ff6aabd9c0 Honor standard HTTP headers for sourceIP (#8233)
Behind load balancers we should be tracing sourceIP
preserved by load balancers.
2019-09-13 03:59:59 +05:30

234 lines
6.3 KiB
Go

/*
* MinIO Cloud Storage, (C) 2017 MinIO, Inc.
*
* 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 cmd
import (
"bytes"
"fmt"
"io"
"io/ioutil"
"net"
"net/http"
"reflect"
"runtime"
"strconv"
"strings"
"time"
"github.com/minio/minio/cmd/logger"
"github.com/minio/minio/pkg/handlers"
trace "github.com/minio/minio/pkg/trace"
)
var traceBodyPlaceHolder = []byte("<BODY>")
// recordRequest - records the first recLen bytes
// of a given io.Reader
type recordRequest struct {
// Data source to record
io.Reader
// Response body should be logged
logBody bool
// Internal recording buffer
buf bytes.Buffer
// request headers
headers http.Header
// total bytes read including header size
bytesRead int
}
func (r *recordRequest) Read(p []byte) (n int, err error) {
n, err = r.Reader.Read(p)
r.bytesRead += n
if r.logBody {
r.buf.Write(p[:n])
}
if err != nil {
return n, err
}
return n, err
}
func (r *recordRequest) Size() int {
sz := r.bytesRead
for k, v := range r.headers {
sz += len(k) + len(v)
}
return sz
}
// Return the bytes that were recorded.
func (r *recordRequest) Data() []byte {
// If body logging is enabled then we return the actual body
if r.logBody {
return r.buf.Bytes()
}
// ... otherwise we return <BODY> placeholder
return traceBodyPlaceHolder
}
// recordResponseWriter - records the first recLen bytes
// of a given http.ResponseWriter
type recordResponseWriter struct {
// Data source to record
http.ResponseWriter
// Response body should be logged
logBody bool
// Internal recording buffer
headers bytes.Buffer
body bytes.Buffer
// The status code of the current HTTP request
statusCode int
// Indicate if headers are written in the log
headersLogged bool
// number of bytes written
bytesWritten int
}
// Write the headers into the given buffer
func (r *recordResponseWriter) writeHeaders(w io.Writer, statusCode int, headers http.Header) {
n, _ := fmt.Fprintf(w, "%d %s\n", statusCode, http.StatusText(statusCode))
r.bytesWritten += n
for k, v := range headers {
n, _ := fmt.Fprintf(w, "%s: %s\n", k, v[0])
r.bytesWritten += n
}
}
// Record the headers.
func (r *recordResponseWriter) WriteHeader(i int) {
r.statusCode = i
if !r.headersLogged {
r.writeHeaders(&r.headers, i, r.ResponseWriter.Header())
r.headersLogged = true
}
r.ResponseWriter.WriteHeader(i)
}
func (r *recordResponseWriter) Write(p []byte) (n int, err error) {
n, err = r.ResponseWriter.Write(p)
r.bytesWritten += n
if !r.headersLogged {
// We assume the response code to be '200 OK' when WriteHeader() is not called,
// that way following Golang HTTP response behavior.
r.writeHeaders(&r.headers, http.StatusOK, r.ResponseWriter.Header())
r.headersLogged = true
}
if r.statusCode >= http.StatusBadRequest || r.logBody {
// Always logging error responses.
r.body.Write(p)
}
return n, err
}
func (r *recordResponseWriter) Size() int {
return r.bytesWritten
}
// Calls the underlying Flush.
func (r *recordResponseWriter) Flush() {
r.ResponseWriter.(http.Flusher).Flush()
}
// Return response body.
func (r *recordResponseWriter) Body() []byte {
// If there was an error response or body logging is enabled
// then we return the body contents
if r.statusCode >= http.StatusBadRequest || r.logBody {
return r.body.Bytes()
}
// ... otherwise we return the <BODY> place holder
return traceBodyPlaceHolder
}
// getOpName sanitizes the operation name for mc
func getOpName(name string) (op string) {
op = strings.TrimPrefix(name, "github.com/minio/minio/cmd.")
op = strings.TrimSuffix(op, "Handler-fm")
op = strings.Replace(op, "objectAPIHandlers", "s3", 1)
op = strings.Replace(op, "webAPIHandlers", "s3", 1)
op = strings.Replace(op, "adminAPIHandlers", "admin", 1)
op = strings.Replace(op, "(*storageRESTServer)", "internal", 1)
op = strings.Replace(op, "(*peerRESTServer)", "internal", 1)
op = strings.Replace(op, "(*lockRESTServer)", "internal", 1)
op = strings.Replace(op, "stsAPIHandlers", "sts", 1)
op = strings.Replace(op, "LivenessCheckHandler", "healthcheck", 1)
op = strings.Replace(op, "ReadinessCheckHandler", "healthcheck", 1)
return op
}
// Trace gets trace of http request
func Trace(f http.HandlerFunc, logBody bool, w http.ResponseWriter, r *http.Request) trace.Info {
name := getOpName(runtime.FuncForPC(reflect.ValueOf(f).Pointer()).Name())
// Setup a http request body recorder
reqHeaders := r.Header.Clone()
reqHeaders.Set("Content-Length", strconv.Itoa(int(r.ContentLength)))
reqHeaders.Set("Host", r.Host)
for _, enc := range r.TransferEncoding {
reqHeaders.Add("Transfer-Encoding", enc)
}
var reqBodyRecorder *recordRequest
t := trace.Info{FuncName: name}
reqBodyRecorder = &recordRequest{Reader: r.Body, logBody: logBody, headers: reqHeaders}
r.Body = ioutil.NopCloser(reqBodyRecorder)
t.NodeName = r.Host
if globalIsDistXL {
t.NodeName = GetLocalPeer(globalEndpoints)
}
// strip port from the host address
if host, _, err := net.SplitHostPort(t.NodeName); err == nil {
t.NodeName = host
}
rq := trace.RequestInfo{
Time: time.Now().UTC(),
Method: r.Method,
Path: r.URL.Path,
RawQuery: r.URL.RawQuery,
Client: handlers.GetSourceIP(r),
Headers: reqHeaders,
Body: reqBodyRecorder.Data(),
}
// Setup a http response body recorder
respBodyRecorder := &recordResponseWriter{ResponseWriter: w, logBody: logBody}
f(logger.NewResponseWriter(respBodyRecorder), r)
rs := trace.ResponseInfo{
Time: time.Now().UTC(),
Headers: respBodyRecorder.Header().Clone(),
StatusCode: respBodyRecorder.statusCode,
Body: respBodyRecorder.Body(),
}
if rs.StatusCode == 0 {
rs.StatusCode = http.StatusOK
}
t.ReqInfo = rq
t.RespInfo = rs
t.CallStats = trace.CallStats{
Latency: rs.Time.Sub(rq.Time),
InputBytes: reqBodyRecorder.Size(),
OutputBytes: respBodyRecorder.Size(),
}
return t
}