github.com/braveheart12/insolar-09-08-19@v0.8.7/network/transport/relay/relay.go (about)

     1  /*
     2   * The Clear BSD License
     3   *
     4   * Copyright (c) 2019 Insolar Technologies
     5   *
     6   * All rights reserved.
     7   *
     8   * Redistribution and use in source and binary forms, with or without modification, are permitted (subject to the limitations in the disclaimer below) provided that the following conditions are met:
     9   *
    10   *  Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
    11   *  Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
    12   *  Neither the name of Insolar Technologies nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
    13   *
    14   * NO EXPRESS OR IMPLIED LICENSES TO ANY PARTY'S PATENT RIGHTS ARE GRANTED BY THIS LICENSE. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    15   *
    16   */
    17  
    18  package relay
    19  
    20  import (
    21  	"github.com/insolar/insolar/core"
    22  	"github.com/insolar/insolar/network/transport/host"
    23  
    24  	"errors"
    25  )
    26  
    27  // State is alias for relaying state
    28  type State int
    29  
    30  const (
    31  	// Unknown unknown relay state.
    32  	Unknown = State(iota + 1)
    33  	// Started is relay type means relaying started.
    34  	Started
    35  	// Stopped is relay type means relaying stopped.
    36  	Stopped
    37  	// Error is relay type means error state change.
    38  	Error
    39  	// NoAuth - this error returns if host tries to send relay request but not authenticated.
    40  	NoAuth
    41  )
    42  
    43  // Relay Interface for relaying
    44  type Relay interface {
    45  	// AddClient add client to relay list.
    46  	AddClient(host *host.Host) error
    47  	// RemoveClient removes client from relay list.
    48  	RemoveClient(host *host.Host) error
    49  	// ClientsCount - clients count.
    50  	ClientsCount() int
    51  	// NeedToRelay returns true if origin host is proxy for target host.
    52  	NeedToRelay(targetAddress string) bool
    53  }
    54  
    55  type relay struct {
    56  	clients []*host.Host
    57  }
    58  
    59  // NewRelay constructs relay list.
    60  func NewRelay() Relay {
    61  	return &relay{
    62  		clients: make([]*host.Host, 0),
    63  	}
    64  }
    65  
    66  // AddClient add client to relay list.
    67  func (r *relay) AddClient(host *host.Host) error {
    68  	if _, n := r.findClient(host.NodeID); n != nil {
    69  		return errors.New("client exists already")
    70  	}
    71  	r.clients = append(r.clients, host)
    72  	return nil
    73  }
    74  
    75  // RemoveClient removes client from relay list.
    76  func (r *relay) RemoveClient(host *host.Host) error {
    77  	idx, n := r.findClient(host.NodeID)
    78  	if n == nil {
    79  		return errors.New("client not found")
    80  	}
    81  	r.clients = append(r.clients[:idx], r.clients[idx+1:]...)
    82  	return nil
    83  }
    84  
    85  // ClientsCount - returns clients count.
    86  func (r *relay) ClientsCount() int {
    87  	return len(r.clients)
    88  }
    89  
    90  // NeedToRelay returns true if origin host is proxy for target host.
    91  func (r *relay) NeedToRelay(targetAddress string) bool {
    92  	for i := 0; i < r.ClientsCount(); i++ {
    93  		if r.clients[i].Address.String() == targetAddress {
    94  			return true
    95  		}
    96  	}
    97  	return false
    98  }
    99  
   100  func (r *relay) findClient(id core.RecordRef) (int, *host.Host) {
   101  	for idx, hostIterator := range r.clients {
   102  		if hostIterator.NodeID.Equal(id) {
   103  			return idx, hostIterator
   104  		}
   105  	}
   106  	return -1, nil
   107  }