github.com/minio/mc@v0.0.0-20240503112107-b471de8d1882/pkg/httptracer/httptracer.go (about)

     1  // Copyright (c) 2015-2021 MinIO, Inc.
     2  //
     3  // This file is part of MinIO Object Storage stack
     4  //
     5  // This program is free software: you can redistribute it and/or modify
     6  // it under the terms of the GNU Affero General Public License as published by
     7  // the Free Software Foundation, either version 3 of the License, or
     8  // (at your option) any later version.
     9  //
    10  // This program is distributed in the hope that it will be useful
    11  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    12  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    13  // GNU Affero General Public License for more details.
    14  //
    15  // You should have received a copy of the GNU Affero General Public License
    16  // along with this program.  If not, see <http://www.gnu.org/licenses/>.
    17  
    18  // Package httptracer implements http tracing functionality
    19  package httptracer
    20  
    21  import (
    22  	"errors"
    23  	"net/http"
    24  	"time"
    25  
    26  	"github.com/minio/pkg/v2/console"
    27  )
    28  
    29  // HTTPTracer provides callback hook mechanism for HTTP transport.
    30  type HTTPTracer interface {
    31  	Request(req *http.Request) error
    32  	Response(res *http.Response) error
    33  }
    34  
    35  // RoundTripTrace interposes HTTP transport requests and respsonses using HTTPTracer hooks
    36  type RoundTripTrace struct {
    37  	Trace     HTTPTracer        // User provides callback methods
    38  	Transport http.RoundTripper // HTTP transport that needs to be intercepted
    39  }
    40  
    41  // RoundTrip executes user provided request and response hooks for each HTTP call.
    42  func (t RoundTripTrace) RoundTrip(req *http.Request) (res *http.Response, err error) {
    43  	timeStamp := time.Now()
    44  
    45  	if t.Transport == nil {
    46  		return nil, errors.New("Invalid Argument")
    47  	}
    48  
    49  	res, err = t.Transport.RoundTrip(req)
    50  	if err != nil {
    51  		return res, err
    52  	}
    53  
    54  	if t.Trace != nil {
    55  		err = t.Trace.Request(req)
    56  		if err != nil {
    57  			return nil, err
    58  		}
    59  
    60  		err = t.Trace.Response(res)
    61  		if err != nil {
    62  			return nil, err
    63  		}
    64  		console.Debugln("Response Time: ", time.Since(timeStamp).String()+"\n")
    65  	}
    66  	return res, err
    67  }
    68  
    69  // GetNewTraceTransport returns a traceable transport
    70  //
    71  // Takes first argument a custom tracer which implements Response, Request() conforming to HTTPTracer interface.
    72  // Another argument can be a default transport or a custom http.RoundTripper implementation
    73  func GetNewTraceTransport(trace HTTPTracer, transport http.RoundTripper) RoundTripTrace {
    74  	return RoundTripTrace{
    75  		Trace:     trace,
    76  		Transport: transport,
    77  	}
    78  }