github.com/sberex/go-sberex@v1.8.2-0.20181113200658-ed96ac38f7d7/p2p/discv5/topic_test.go (about)

     1  // This file is part of the go-sberex library. The go-sberex library is 
     2  // free software: you can redistribute it and/or modify it under the terms 
     3  // of the GNU Lesser General Public License as published by the Free 
     4  // Software Foundation, either version 3 of the License, or (at your option)
     5  // any later version.
     6  //
     7  // The go-sberex library is distributed in the hope that it will be useful, 
     8  // but WITHOUT ANY WARRANTY; without even the implied warranty of
     9  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser 
    10  // General Public License <http://www.gnu.org/licenses/> for more details.
    11  
    12  package discv5
    13  
    14  import (
    15  	"encoding/binary"
    16  	"testing"
    17  	"time"
    18  
    19  	"github.com/Sberex/go-sberex/common"
    20  	"github.com/Sberex/go-sberex/common/mclock"
    21  )
    22  
    23  func TestTopicRadius(t *testing.T) {
    24  	now := mclock.Now()
    25  	topic := Topic("qwerty")
    26  	rad := newTopicRadius(topic)
    27  	targetRad := (^uint64(0)) / 100
    28  
    29  	waitFn := func(addr common.Hash) time.Duration {
    30  		prefix := binary.BigEndian.Uint64(addr[0:8])
    31  		dist := prefix ^ rad.topicHashPrefix
    32  		relDist := float64(dist) / float64(targetRad)
    33  		relTime := (1 - relDist/2) * 2
    34  		if relTime < 0 {
    35  			relTime = 0
    36  		}
    37  		return time.Duration(float64(targetWaitTime) * relTime)
    38  	}
    39  
    40  	bcnt := 0
    41  	cnt := 0
    42  	var sum float64
    43  	for cnt < 100 {
    44  		addr := rad.nextTarget(false).target
    45  		wait := waitFn(addr)
    46  		ticket := &ticket{
    47  			topics:  []Topic{topic},
    48  			regTime: []mclock.AbsTime{mclock.AbsTime(wait)},
    49  			node:    &Node{nodeNetGuts: nodeNetGuts{sha: addr}},
    50  		}
    51  		rad.adjustWithTicket(now, addr, ticketRef{ticket, 0})
    52  		if rad.radius != maxRadius {
    53  			cnt++
    54  			sum += float64(rad.radius)
    55  		} else {
    56  			bcnt++
    57  			if bcnt > 500 {
    58  				t.Errorf("Radius did not converge in 500 iterations")
    59  			}
    60  		}
    61  	}
    62  	avgRel := sum / float64(cnt) / float64(targetRad)
    63  	if avgRel > 1.05 || avgRel < 0.95 {
    64  		t.Errorf("Average/target ratio is too far from 1 (%v)", avgRel)
    65  	}
    66  }