github.com/Heebron/moby@v0.0.0-20221111184709-6eab4f55faf7/libnetwork/networkdb/nodemgmt.go (about)

     1  package networkdb
     2  
     3  import (
     4  	"fmt"
     5  
     6  	"github.com/hashicorp/memberlist"
     7  	"github.com/sirupsen/logrus"
     8  )
     9  
    10  type nodeState int
    11  
    12  const (
    13  	nodeNotFound    nodeState = -1
    14  	nodeActiveState nodeState = 0
    15  	nodeLeftState   nodeState = 1
    16  	nodeFailedState nodeState = 2
    17  )
    18  
    19  var nodeStateName = map[nodeState]string{
    20  	-1: "NodeNotFound",
    21  	0:  "NodeActive",
    22  	1:  "NodeLeft",
    23  	2:  "NodeFailed",
    24  }
    25  
    26  // findNode search the node into the 3 node lists and returns the node pointer and the list
    27  // where it got found
    28  func (nDB *NetworkDB) findNode(nodeName string) (*node, nodeState, map[string]*node) {
    29  	for i, nodes := range []map[string]*node{
    30  		nDB.nodes,
    31  		nDB.leftNodes,
    32  		nDB.failedNodes,
    33  	} {
    34  		if n, ok := nodes[nodeName]; ok {
    35  			return n, nodeState(i), nodes
    36  		}
    37  	}
    38  	return nil, nodeNotFound, nil
    39  }
    40  
    41  // changeNodeState changes the state of the node specified, returns true if the node was moved,
    42  // false if there was no need to change the node state. Error will be returned if the node does not
    43  // exists
    44  func (nDB *NetworkDB) changeNodeState(nodeName string, newState nodeState) (bool, error) {
    45  	n, currState, m := nDB.findNode(nodeName)
    46  	if n == nil {
    47  		return false, fmt.Errorf("node %s not found", nodeName)
    48  	}
    49  
    50  	switch newState {
    51  	case nodeActiveState:
    52  		if currState == nodeActiveState {
    53  			return false, nil
    54  		}
    55  
    56  		delete(m, nodeName)
    57  		// reset the node reap time
    58  		n.reapTime = 0
    59  		nDB.nodes[nodeName] = n
    60  	case nodeLeftState:
    61  		if currState == nodeLeftState {
    62  			return false, nil
    63  		}
    64  
    65  		delete(m, nodeName)
    66  		nDB.leftNodes[nodeName] = n
    67  	case nodeFailedState:
    68  		if currState == nodeFailedState {
    69  			return false, nil
    70  		}
    71  
    72  		delete(m, nodeName)
    73  		nDB.failedNodes[nodeName] = n
    74  	}
    75  
    76  	logrus.Infof("Node %s change state %s --> %s", nodeName, nodeStateName[currState], nodeStateName[newState])
    77  
    78  	if newState == nodeLeftState || newState == nodeFailedState {
    79  		// set the node reap time, if not already set
    80  		// It is possible that a node passes from failed to left and the reaptime was already set so keep that value
    81  		if n.reapTime == 0 {
    82  			n.reapTime = nodeReapInterval
    83  		}
    84  		// The node leave or fails, delete all the entries created by it.
    85  		// If the node was temporary down, deleting the entries will guarantee that the CREATE events will be accepted
    86  		// If the node instead left because was going down, then it makes sense to just delete all its state
    87  		nDB.deleteNodeFromNetworks(n.Name)
    88  		nDB.deleteNodeTableEntries(n.Name)
    89  	}
    90  
    91  	return true, nil
    92  }
    93  
    94  func (nDB *NetworkDB) purgeReincarnation(mn *memberlist.Node) bool {
    95  	for name, node := range nDB.nodes {
    96  		if node.Addr.Equal(mn.Addr) && node.Port == mn.Port && mn.Name != name {
    97  			logrus.Infof("Node %s/%s, is the new incarnation of the active node %s/%s", mn.Name, mn.Addr, name, node.Addr)
    98  			nDB.changeNodeState(name, nodeLeftState)
    99  			return true
   100  		}
   101  	}
   102  
   103  	for name, node := range nDB.failedNodes {
   104  		if node.Addr.Equal(mn.Addr) && node.Port == mn.Port && mn.Name != name {
   105  			logrus.Infof("Node %s/%s, is the new incarnation of the failed node %s/%s", mn.Name, mn.Addr, name, node.Addr)
   106  			nDB.changeNodeState(name, nodeLeftState)
   107  			return true
   108  		}
   109  	}
   110  
   111  	for name, node := range nDB.leftNodes {
   112  		if node.Addr.Equal(mn.Addr) && node.Port == mn.Port && mn.Name != name {
   113  			logrus.Infof("Node %s/%s, is the new incarnation of the shutdown node %s/%s", mn.Name, mn.Addr, name, node.Addr)
   114  			nDB.changeNodeState(name, nodeLeftState)
   115  			return true
   116  		}
   117  	}
   118  
   119  	return false
   120  }