istio.io/istio@v0.0.0-20240520182934-d79c90f27776/pilot/pkg/autoregistration/connections.go (about)

     1  // Copyright Istio Authors
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package autoregistration
    16  
    17  import (
    18  	"sync"
    19  	"time"
    20  
    21  	"k8s.io/apimachinery/pkg/types"
    22  
    23  	"istio.io/istio/pilot/pkg/model"
    24  	"istio.io/istio/pkg/maps"
    25  )
    26  
    27  // connection from a proxy to a control plane.
    28  // This interface exists to avoid circular reference to xds.Connection as well
    29  // as keeps the API surface scoped to what we need for auto-registration logic.
    30  type connection interface {
    31  	ID() string
    32  	Proxy() *model.Proxy
    33  	ConnectedAt() time.Time
    34  	Stop()
    35  }
    36  
    37  // a single proxy may have multiple connections, so we track them here
    38  // when a WorkloadGroup is deleted, we can force disconnects
    39  // when OnDisconnect occurs, we only trigger cleanup when there are no more connections for that proxy
    40  type adsConnections struct {
    41  	sync.Mutex
    42  
    43  	// keyed by proxy id, then connection id
    44  	byProxy map[proxyKey]map[string]connection
    45  }
    46  
    47  func newAdsConnections() *adsConnections {
    48  	return &adsConnections{byProxy: map[proxyKey]map[string]connection{}}
    49  }
    50  
    51  func (m *adsConnections) ConnectionsForGroup(wg types.NamespacedName) []connection {
    52  	// collect the proxies that should be disconnected (don't remove them, OnDisconnect will)
    53  	m.Lock()
    54  	defer m.Unlock()
    55  	var conns []connection
    56  	for key, connections := range m.byProxy {
    57  		if key.GroupName == wg.Name && key.Namespace == wg.Namespace {
    58  			conns = append(conns, maps.Values(connections)...)
    59  		}
    60  	}
    61  	return conns
    62  }
    63  
    64  func (m *adsConnections) Connect(conn connection) {
    65  	m.Lock()
    66  	defer m.Unlock()
    67  	k := makeProxyKey(conn.Proxy())
    68  
    69  	connections := m.byProxy[k]
    70  	if connections == nil {
    71  		connections = make(map[string]connection)
    72  		m.byProxy[k] = connections
    73  	}
    74  	connections[conn.ID()] = conn
    75  }
    76  
    77  // Disconnect tracks disconnect events of ads clients.
    78  // Returns false once there are no more connections for the given proxy.
    79  func (m *adsConnections) Disconnect(conn connection) bool {
    80  	m.Lock()
    81  	defer m.Unlock()
    82  
    83  	k := makeProxyKey(conn.Proxy())
    84  	connections := m.byProxy[k]
    85  	if connections == nil {
    86  		return false
    87  	}
    88  
    89  	id := conn.ID()
    90  	delete(connections, id)
    91  	if len(connections) == 0 {
    92  		delete(m.byProxy, k)
    93  		return false
    94  	}
    95  
    96  	return true
    97  }
    98  
    99  // keys required to uniquely ID a single proxy
   100  type proxyKey struct {
   101  	Network   string
   102  	IP        string
   103  	GroupName string
   104  	Namespace string
   105  }
   106  
   107  func makeProxyKey(proxy *model.Proxy) proxyKey {
   108  	return proxyKey{
   109  		Network:   string(proxy.Metadata.Network),
   110  		IP:        proxy.IPAddresses[0],
   111  		GroupName: proxy.Metadata.AutoRegisterGroup,
   112  		Namespace: proxy.Metadata.Namespace,
   113  	}
   114  }