minio/pkg/madmin/api-trace.go

93 lines
2.4 KiB
Go

/*
* MinIO Cloud Storage, (C) 2019 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 madmin
import (
"bufio"
"encoding/json"
"io"
"net/http"
"net/url"
"strconv"
trace "github.com/minio/minio/pkg/trace"
)
// TraceInfo holds http trace
type TraceInfo struct {
Trace trace.Info
Err error `json:"-"`
}
// Trace - listen on http trace notifications.
func (adm AdminClient) Trace(allTrace bool, doneCh <-chan struct{}) <-chan TraceInfo {
traceInfoCh := make(chan TraceInfo, 1)
// Only success, start a routine to start reading line by line.
go func(traceInfoCh chan<- TraceInfo) {
defer close(traceInfoCh)
for {
urlValues := make(url.Values)
urlValues.Set("all", strconv.FormatBool(allTrace))
reqData := requestData{
relPath: "/v1/trace",
queryValues: urlValues,
}
// Execute GET to call trace handler
resp, err := adm.executeMethod("GET", reqData)
if err != nil {
closeResponse(resp)
return
}
if resp.StatusCode != http.StatusOK {
traceInfoCh <- TraceInfo{Err: httpRespToErrorResponse(resp)}
return
}
// Initialize a new bufio scanner, to read line by line.
bio := bufio.NewScanner(resp.Body)
// Close the response body.
defer resp.Body.Close()
// Unmarshal each line, returns marshaled values.
for bio.Scan() {
var traceRec trace.Info
if err = json.Unmarshal(bio.Bytes(), &traceRec); err != nil {
continue
}
select {
case <-doneCh:
return
case traceInfoCh <- TraceInfo{Trace: traceRec}:
}
}
// Look for any underlying errors.
if err = bio.Err(); err != nil {
// For an unexpected connection drop from server, we close the body
// and re-connect.
if err == io.ErrUnexpectedEOF {
resp.Body.Close()
}
}
}
}(traceInfoCh)
// Returns the trace info channel, for caller to start reading from.
return traceInfoCh
}