github.com/defanghe/fabric@v2.1.1+incompatible/gossip/comm/comm.go (about)

     1  /*
     2  Copyright IBM Corp. All Rights Reserved.
     3  
     4  SPDX-License-Identifier: Apache-2.0
     5  */
     6  
     7  package comm
     8  
     9  import (
    10  	"encoding/json"
    11  	"fmt"
    12  	"time"
    13  
    14  	"github.com/hyperledger/fabric/gossip/api"
    15  	"github.com/hyperledger/fabric/gossip/common"
    16  	"github.com/hyperledger/fabric/gossip/protoext"
    17  )
    18  
    19  // Comm is an object that enables to communicate with other peers
    20  // that also embed a CommModule.
    21  type Comm interface {
    22  
    23  	// GetPKIid returns this instance's PKI id
    24  	GetPKIid() common.PKIidType
    25  
    26  	// Send sends a message to remote peers asynchronously
    27  	Send(msg *protoext.SignedGossipMessage, peers ...*RemotePeer)
    28  
    29  	// SendWithAck sends a message to remote peers, waiting for acknowledgement from minAck of them, or until a certain timeout expires
    30  	SendWithAck(msg *protoext.SignedGossipMessage, timeout time.Duration, minAck int, peers ...*RemotePeer) AggregatedSendResult
    31  
    32  	// Probe probes a remote node and returns nil if its responsive,
    33  	// and an error if it's not.
    34  	Probe(peer *RemotePeer) error
    35  
    36  	// Handshake authenticates a remote peer and returns
    37  	// (its identity, nil) on success and (nil, error)
    38  	Handshake(peer *RemotePeer) (api.PeerIdentityType, error)
    39  
    40  	// Accept returns a dedicated read-only channel for messages sent by other nodes that match a certain predicate.
    41  	// Each message from the channel can be used to send a reply back to the sender
    42  	Accept(common.MessageAcceptor) <-chan protoext.ReceivedMessage
    43  
    44  	// PresumedDead returns a read-only channel for node endpoints that are suspected to be offline
    45  	PresumedDead() <-chan common.PKIidType
    46  
    47  	// IdentitySwitch returns a read-only channel about identity change events
    48  	IdentitySwitch() <-chan common.PKIidType
    49  
    50  	// CloseConn closes a connection to a certain endpoint
    51  	CloseConn(peer *RemotePeer)
    52  
    53  	// Stop stops the module
    54  	Stop()
    55  }
    56  
    57  // RemotePeer defines a peer's endpoint and its PKIid
    58  type RemotePeer struct {
    59  	Endpoint string
    60  	PKIID    common.PKIidType
    61  }
    62  
    63  // SendResult defines a result of a send to a remote peer
    64  type SendResult struct {
    65  	error
    66  	RemotePeer
    67  }
    68  
    69  // Error returns the error of the SendResult, or an empty string
    70  // if an error hasn't occurred
    71  func (sr SendResult) Error() string {
    72  	if sr.error != nil {
    73  		return sr.error.Error()
    74  	}
    75  	return ""
    76  }
    77  
    78  // AggregatedSendResult represents a slice of SendResults
    79  type AggregatedSendResult []SendResult
    80  
    81  // AckCount returns the number of successful acknowledgements
    82  func (ar AggregatedSendResult) AckCount() int {
    83  	c := 0
    84  	for _, ack := range ar {
    85  		if ack.error == nil {
    86  			c++
    87  		}
    88  	}
    89  	return c
    90  }
    91  
    92  // NackCount returns the number of unsuccessful acknowledgements
    93  func (ar AggregatedSendResult) NackCount() int {
    94  	return len(ar) - ar.AckCount()
    95  }
    96  
    97  // String returns a JSONed string representation
    98  // of the AggregatedSendResult
    99  func (ar AggregatedSendResult) String() string {
   100  	errMap := map[string]int{}
   101  	for _, ack := range ar {
   102  		if ack.error == nil {
   103  			continue
   104  		}
   105  		errMap[ack.Error()]++
   106  	}
   107  
   108  	ackCount := ar.AckCount()
   109  	output := map[string]interface{}{}
   110  	if ackCount > 0 {
   111  		output["successes"] = ackCount
   112  	}
   113  	if ackCount < len(ar) {
   114  		output["failures"] = errMap
   115  	}
   116  	b, _ := json.Marshal(output)
   117  	return string(b)
   118  }
   119  
   120  // String converts a RemotePeer to a string
   121  func (p *RemotePeer) String() string {
   122  	return fmt.Sprintf("%s, PKIid:%v", p.Endpoint, p.PKIID)
   123  }