github.com/aigarnetwork/aigar@v0.0.0-20191115204914-d59a6eb70f8e/cmd/devp2p/nodeset.go (about)

     1  //  Copyright 2018 The go-ethereum Authors
     2  //  Copyright 2019 The go-aigar Authors
     3  //  This file is part of the go-aigar library.
     4  //
     5  //  The go-aigar library is free software: you can redistribute it and/or modify
     6  //  it under the terms of the GNU Lesser 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  //  The go-aigar library 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 Lesser General Public License for more details.
    14  //
    15  //  You should have received a copy of the GNU Lesser General Public License
    16  //  along with the go-aigar library. If not, see <http://www.gnu.org/licenses/>.
    17  
    18  package main
    19  
    20  import (
    21  	"bytes"
    22  	"encoding/json"
    23  	"fmt"
    24  	"io/ioutil"
    25  	"os"
    26  	"sort"
    27  	"time"
    28  
    29  	"github.com/AigarNetwork/aigar/common"
    30  	"github.com/AigarNetwork/aigar/p2p/enode"
    31  )
    32  
    33  const jsonIndent = "    "
    34  
    35  // nodeSet is the nodes.json file format. It holds a set of node records
    36  // as a JSON object.
    37  type nodeSet map[enode.ID]nodeJSON
    38  
    39  type nodeJSON struct {
    40  	Seq uint64      `json:"seq"`
    41  	N   *enode.Node `json:"record"`
    42  
    43  	// The score tracks how many liveness checks were performed. It is incremented by one
    44  	// every time the node passes a check, and halved every time it doesn't.
    45  	Score int `json:"score,omitempty"`
    46  	// These two track the time of last successful contact.
    47  	FirstResponse time.Time `json:"firstResponse,omitempty"`
    48  	LastResponse  time.Time `json:"lastResponse,omitempty"`
    49  	// This one tracks the time of our last attempt to contact the node.
    50  	LastCheck time.Time `json:"lastCheck,omitempty"`
    51  }
    52  
    53  func loadNodesJSON(file string) nodeSet {
    54  	var nodes nodeSet
    55  	if err := common.LoadJSON(file, &nodes); err != nil {
    56  		exit(err)
    57  	}
    58  	return nodes
    59  }
    60  
    61  func writeNodesJSON(file string, nodes nodeSet) {
    62  	nodesJSON, err := json.MarshalIndent(nodes, "", jsonIndent)
    63  	if err != nil {
    64  		exit(err)
    65  	}
    66  	if file == "-" {
    67  		os.Stdout.Write(nodesJSON)
    68  		return
    69  	}
    70  	if err := ioutil.WriteFile(file, nodesJSON, 0644); err != nil {
    71  		exit(err)
    72  	}
    73  }
    74  
    75  func (ns nodeSet) nodes() []*enode.Node {
    76  	result := make([]*enode.Node, 0, len(ns))
    77  	for _, n := range ns {
    78  		result = append(result, n.N)
    79  	}
    80  	// Sort by ID.
    81  	sort.Slice(result, func(i, j int) bool {
    82  		return bytes.Compare(result[i].ID().Bytes(), result[j].ID().Bytes()) < 0
    83  	})
    84  	return result
    85  }
    86  
    87  func (ns nodeSet) add(nodes ...*enode.Node) {
    88  	for _, n := range nodes {
    89  		ns[n.ID()] = nodeJSON{Seq: n.Seq(), N: n}
    90  	}
    91  }
    92  
    93  func (ns nodeSet) verify() error {
    94  	for id, n := range ns {
    95  		if n.N.ID() != id {
    96  			return fmt.Errorf("invalid node %v: ID does not match ID %v in record", id, n.N.ID())
    97  		}
    98  		if n.N.Seq() != n.Seq {
    99  			return fmt.Errorf("invalid node %v: 'seq' does not match seq %d from record", id, n.N.Seq())
   100  		}
   101  	}
   102  	return nil
   103  }