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Move RPC router from Client/Server and into BaseDeps (#8559) 

This will allow it to be a shared component which is needed for AutoConfig
This commit is contained in:
Matt Keeler 2020-08-27 11:23:52 -04:00 committed by GitHub
parent 5e2f0be305
commit 106e1d50bd
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
15 changed files with 240 additions and 52 deletions
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6
agent/agent.go
View File

@ -18,6 +18,7 @@ import (
"time"
"github.com/hashicorp/consul/agent/dns"
"github.com/hashicorp/consul/agent/router"
"github.com/hashicorp/go-connlimit"
"github.com/hashicorp/go-hclog"
"github.com/hashicorp/go-memdb"
@ -306,6 +307,9 @@ type Agent struct {
// Connection Pool
connPool *pool.ConnPool
// Shared RPC Router
router *router.Router
// enterpriseAgent embeds fields that we only access in consul-enterprise builds
enterpriseAgent
}
@ -351,6 +355,7 @@ func New(bd BaseDeps) (*Agent, error) {
MemSink: bd.MetricsHandler,
connPool: bd.ConnPool,
autoConf: bd.AutoConfig,
router: bd.Router,
}
a.serviceManager = NewServiceManager(&a)
@ -462,6 +467,7 @@ func (a *Agent) Start(ctx context.Context) error {
consul.WithTokenStore(a.tokens),
consul.WithTLSConfigurator(a.tlsConfigurator),
consul.WithConnectionPool(a.connPool),
consul.WithRouter(a.router),
}
// Setup either the client or the server.

30
agent/agent_test.go
View File

@ -4741,3 +4741,33 @@ func TestAgent_AutoEncrypt(t *testing.T) {
require.Len(t, x509Cert.URIs, 1)
require.Equal(t, id.URI(), x509Cert.URIs[0])
}
func TestSharedRPCRouter(t *testing.T) {
// this test runs both a server and client and ensures that the shared
// router is being used. It would be possible for the Client and Server
// types to create and use their own routers and for RPCs such as the
// ones used in WaitForTestAgent to succeed. However accessing the
// router stored on the agent ensures that Serf information from the
// Client/Server types are being set in the same shared rpc router.
srv := NewTestAgent(t, "")
defer srv.Shutdown()
testrpc.WaitForTestAgent(t, srv.RPC, "dc1")
mgr, server := srv.Agent.router.FindLANRoute()
require.NotNil(t, mgr)
require.NotNil(t, server)
client := NewTestAgent(t, `
server = false
bootstrap = false
retry_join = ["`+srv.Config.SerfBindAddrLAN.String()+`"]
`)
testrpc.WaitForTestAgent(t, client.RPC, "dc1")
mgr, server = client.Agent.router.FindLANRoute()
require.NotNil(t, mgr)
require.NotNil(t, server)
}

2
agent/consul/auto_encrypt.go
View File

@ -73,7 +73,7 @@ func (c *Client) RequestAutoEncryptCerts(ctx context.Context, servers []string,
// Check if we know about a server already through gossip. Depending on
// how the agent joined, there might already be one. Also in case this
// gets called because the cert expired.
server := c.routers.FindServer()
server := c.router.FindLANServer()
if server != nil {
servers = []string{server.Addr.String()}
}

33
agent/consul/client.go
View File

@ -15,6 +15,7 @@ import (
"github.com/hashicorp/consul/lib"
"github.com/hashicorp/consul/logging"
"github.com/hashicorp/consul/tlsutil"
"github.com/hashicorp/consul/types"
"github.com/hashicorp/go-hclog"
"github.com/hashicorp/serf/serf"
"golang.org/x/time/rate"
@ -59,9 +60,9 @@ type Client struct {
// Connection pool to consul servers
connPool *pool.ConnPool
// routers is responsible for the selection and maintenance of
// router is responsible for the selection and maintenance of
// Consul servers this agent uses for RPC requests
routers *router.Manager
router *router.Router
// rpcLimiter is used to rate limit the total number of RPCs initiated
// from an agent.
@ -120,12 +121,14 @@ func NewClient(config *Config, options ...ConsulOption) (*Client, error) {
}
}
logger := flat.logger.NamedIntercept(logging.ConsulClient)
// Create client
c := &Client{
config: config,
connPool: connPool,
eventCh: make(chan serf.Event, serfEventBacklog),
logger: flat.logger.NamedIntercept(logging.ConsulClient),
logger: logger,
shutdownCh: make(chan struct{}),
tlsConfigurator: tlsConfigurator,
}
@ -160,15 +163,22 @@ func NewClient(config *Config, options ...ConsulOption) (*Client, error) {
return nil, fmt.Errorf("Failed to start lan serf: %v", err)
}
// Start maintenance task for servers
c.routers = router.New(c.logger, c.shutdownCh, c.serf, c.connPool, "")
go c.routers.Start()
rpcRouter := flat.router
if rpcRouter == nil {
rpcRouter = router.NewRouter(logger, config.Datacenter, fmt.Sprintf("%s.%s", config.NodeName, config.Datacenter))
}
if err := rpcRouter.AddArea(types.AreaLAN, c.serf, c.connPool); err != nil {
c.Shutdown()
return nil, fmt.Errorf("Failed to add LAN area to the RPC router: %w", err)
}
c.router = rpcRouter
// Start LAN event handlers after the router is complete since the event
// handlers depend on the router and the router depends on Serf.
go c.lanEventHandler()
// This needs to happen after initializing c.routers to prevent a race
// This needs to happen after initializing c.router to prevent a race
// condition where the router manager is used when the pointer is nil
if c.acls.ACLsEnabled() {
go c.monitorACLMode()
@ -276,7 +286,7 @@ func (c *Client) RPC(method string, args interface{}, reply interface{}) error {
firstCheck := time.Now()
TRY:
server := c.routers.FindServer()
manager, server := c.router.FindLANRoute()
if server == nil {
return structs.ErrNoServers
}
@ -301,7 +311,7 @@ TRY:
"error", rpcErr,
)
metrics.IncrCounterWithLabels([]string{"client", "rpc", "failed"}, 1, []metrics.Label{{Name: "server", Value: server.Name}})
c.routers.NotifyFailedServer(server)
manager.NotifyFailedServer(server)
if retry := canRetry(args, rpcErr); !retry {
return rpcErr
}
@ -323,7 +333,7 @@ TRY:
// operation.
func (c *Client) SnapshotRPC(args *structs.SnapshotRequest, in io.Reader, out io.Writer,
replyFn structs.SnapshotReplyFn) error {
server := c.routers.FindServer()
manager, server := c.router.FindLANRoute()
if server == nil {
return structs.ErrNoServers
}
@ -339,6 +349,7 @@ func (c *Client) SnapshotRPC(args *structs.SnapshotRequest, in io.Reader, out io
var reply structs.SnapshotResponse
snap, err := SnapshotRPC(c.connPool, c.config.Datacenter, server.ShortName, server.Addr, args, in, &reply)
if err != nil {
manager.NotifyFailedServer(server)
return err
}
defer func() {
@ -367,7 +378,7 @@ func (c *Client) SnapshotRPC(args *structs.SnapshotRequest, in io.Reader, out io
// Stats is used to return statistics for debugging and insight
// for various sub-systems
func (c *Client) Stats() map[string]map[string]string {
numServers := c.routers.NumServers()
numServers := c.router.GetLANManager().NumServers()
toString := func(v uint64) string {
return strconv.FormatUint(v, 10)

7
agent/consul/client_serf.go
View File

@ -9,6 +9,7 @@ import (
"github.com/hashicorp/consul/agent/structs"
"github.com/hashicorp/consul/lib"
"github.com/hashicorp/consul/logging"
"github.com/hashicorp/consul/types"
"github.com/hashicorp/go-hclog"
"github.com/hashicorp/serf/serf"
)
@ -115,7 +116,7 @@ func (c *Client) nodeJoin(me serf.MemberEvent) {
continue
}
c.logger.Info("adding server", "server", parts)
c.routers.AddServer(parts)
c.router.AddServer(types.AreaLAN, parts)
// Trigger the callback
if c.config.ServerUp != nil {
@ -139,7 +140,7 @@ func (c *Client) nodeUpdate(me serf.MemberEvent) {
continue
}
c.logger.Info("updating server", "server", parts.String())
c.routers.AddServer(parts)
c.router.AddServer(types.AreaLAN, parts)
}
}
@ -151,7 +152,7 @@ func (c *Client) nodeFail(me serf.MemberEvent) {
continue
}
c.logger.Info("removing server", "server", parts.String())
c.routers.RemoveServer(parts)
c.router.RemoveServer(types.AreaLAN, parts)
}
}

18
agent/consul/client_test.go
View File

@ -112,7 +112,7 @@ func TestClient_JoinLAN(t *testing.T) {
joinLAN(t, c1, s1)
testrpc.WaitForTestAgent(t, c1.RPC, "dc1")
retry.Run(t, func(r *retry.R) {
if got, want := c1.routers.NumServers(), 1; got != want {
if got, want := c1.router.GetLANManager().NumServers(), 1; got != want {
r.Fatalf("got %d servers want %d", got, want)
}
if got, want := len(s1.LANMembers()), 2; got != want {
@ -150,7 +150,7 @@ func TestClient_LANReap(t *testing.T) {
// Check the router has both
retry.Run(t, func(r *retry.R) {
server := c1.routers.FindServer()
server := c1.router.FindLANServer()
require.NotNil(t, server)
require.Equal(t, s1.config.NodeName, server.Name)
})
@ -160,7 +160,7 @@ func TestClient_LANReap(t *testing.T) {
retry.Run(t, func(r *retry.R) {
require.Len(r, c1.LANMembers(), 1)
server := c1.routers.FindServer()
server := c1.router.FindLANServer()
require.Nil(t, server)
})
}
@ -390,7 +390,7 @@ func TestClient_RPC_ConsulServerPing(t *testing.T) {
}
// Sleep to allow Serf to sync, shuffle, and let the shuffle complete
c.routers.ResetRebalanceTimer()
c.router.GetLANManager().ResetRebalanceTimer()
time.Sleep(time.Second)
if len(c.LANMembers()) != numServers+numClients {
@ -406,7 +406,7 @@ func TestClient_RPC_ConsulServerPing(t *testing.T) {
var pingCount int
for range servers {
time.Sleep(200 * time.Millisecond)
s := c.routers.FindServer()
m, s := c.router.FindLANRoute()
ok, err := c.connPool.Ping(s.Datacenter, s.ShortName, s.Addr)
if !ok {
t.Errorf("Unable to ping server %v: %s", s.String(), err)
@ -415,7 +415,7 @@ func TestClient_RPC_ConsulServerPing(t *testing.T) {
// Artificially fail the server in order to rotate the server
// list
c.routers.NotifyFailedServer(s)
m.NotifyFailedServer(s)
}
if pingCount != numServers {
@ -524,7 +524,7 @@ func TestClient_SnapshotRPC(t *testing.T) {
// Wait until we've got a healthy server.
retry.Run(t, func(r *retry.R) {
if got, want := c1.routers.NumServers(), 1; got != want {
if got, want := c1.router.GetLANManager().NumServers(), 1; got != want {
r.Fatalf("got %d servers want %d", got, want)
}
})
@ -559,7 +559,7 @@ func TestClient_SnapshotRPC_RateLimit(t *testing.T) {
joinLAN(t, c1, s1)
retry.Run(t, func(r *retry.R) {
if got, want := c1.routers.NumServers(), 1; got != want {
if got, want := c1.router.GetLANManager().NumServers(), 1; got != want {
r.Fatalf("got %d servers want %d", got, want)
}
})
@ -607,7 +607,7 @@ func TestClient_SnapshotRPC_TLS(t *testing.T) {
}
// Wait until we've got a healthy server.
if got, want := c1.routers.NumServers(), 1; got != want {
if got, want := c1.router.GetLANManager().NumServers(), 1; got != want {
r.Fatalf("got %d servers want %d", got, want)
}
})

24
agent/consul/coordinate_endpoint.go
View File

@ -10,6 +10,7 @@ import (
"github.com/hashicorp/consul/agent/consul/state"
"github.com/hashicorp/consul/agent/structs"
"github.com/hashicorp/consul/logging"
"github.com/hashicorp/consul/types"
"github.com/hashicorp/go-hclog"
"github.com/hashicorp/go-memdb"
)
@ -161,23 +162,32 @@ func (c *Coordinate) Update(args *structs.CoordinateUpdateRequest, reply *struct
// ListDatacenters returns the list of datacenters and their respective nodes
// and the raw coordinates of those nodes (if no coordinates are available for
// any of the nodes, the node list may be empty).
// any of the nodes, the node list may be empty). This endpoint will not return
// information about the LAN network area.
func (c *Coordinate) ListDatacenters(args *struct{}, reply *[]structs.DatacenterMap) error {
maps, err := c.srv.router.GetDatacenterMaps()
if err != nil {
return err
}
var out []structs.DatacenterMap
// Strip the datacenter suffixes from all the node names.
for i := range maps {
suffix := fmt.Sprintf(".%s", maps[i].Datacenter)
for j := range maps[i].Coordinates {
node := maps[i].Coordinates[j].Node
maps[i].Coordinates[j].Node = strings.TrimSuffix(node, suffix)
for _, dcMap := range maps {
if dcMap.AreaID == types.AreaLAN {
continue
}
suffix := fmt.Sprintf(".%s", dcMap.Datacenter)
for j := range dcMap.Coordinates {
node := dcMap.Coordinates[j].Node
dcMap.Coordinates[j].Node = strings.TrimSuffix(node, suffix)
}
out = append(out, dcMap)
}
*reply = maps
*reply = out
return nil
}

8
agent/consul/options.go
View File

@ -2,6 +2,7 @@ package consul
import (
"github.com/hashicorp/consul/agent/pool"
"github.com/hashicorp/consul/agent/router"
"github.com/hashicorp/consul/agent/token"
"github.com/hashicorp/consul/tlsutil"
"github.com/hashicorp/go-hclog"
@ -12,6 +13,7 @@ type consulOptions struct {
tlsConfigurator *tlsutil.Configurator
connPool *pool.ConnPool
tokens *token.Store
router *router.Router
}
type ConsulOption func(*consulOptions)
@ -40,6 +42,12 @@ func WithTokenStore(tokens *token.Store) ConsulOption {
}
}
func WithRouter(router *router.Router) ConsulOption {
return func(opt *consulOptions) {
opt.router = router
}
}
func flattenConsulOptions(options []ConsulOption) consulOptions {
var flat consulOptions
for _, opt := range options {

13
agent/consul/server.go
View File

@ -322,6 +322,7 @@ func NewServer(config *Config, options ...ConsulOption) (*Server, error) {
tokens := flat.tokens
tlsConfigurator := flat.tlsConfigurator
connPool := flat.connPool
rpcRouter := flat.router
if err := config.CheckProtocolVersion(); err != nil {
return nil, err
@ -377,6 +378,11 @@ func NewServer(config *Config, options ...ConsulOption) (*Server, error) {
serverLogger := logger.NamedIntercept(logging.ConsulServer)
loggers := newLoggerStore(serverLogger)
if rpcRouter == nil {
rpcRouter = router.NewRouter(serverLogger, config.Datacenter, fmt.Sprintf("%s.%s", config.NodeName, config.Datacenter))
}
// Create server.
s := &Server{
config: config,
@ -388,7 +394,7 @@ func NewServer(config *Config, options ...ConsulOption) (*Server, error) {
loggers: loggers,
leaveCh: make(chan struct{}),
reconcileCh: make(chan serf.Member, reconcileChSize),
router: router.NewRouter(serverLogger, config.Datacenter, fmt.Sprintf("%s.%s", config.NodeName, config.Datacenter)),
router: rpcRouter,
rpcServer: rpc.NewServer(),
insecureRPCServer: rpc.NewServer(),
tlsConfigurator: tlsConfigurator,
@ -545,6 +551,11 @@ func NewServer(config *Config, options ...ConsulOption) (*Server, error) {
s.Shutdown()
return nil, fmt.Errorf("Failed to start LAN Serf: %v", err)
}
if err := s.router.AddArea(types.AreaLAN, s.serfLAN, s.connPool); err != nil {
s.Shutdown()
return nil, fmt.Errorf("Failed to add LAN serf route: %w", err)
}
go s.lanEventHandler()
// Start the flooders after the LAN event handler is wired up.

2
agent/consul/util.go
View File

@ -156,7 +156,7 @@ func (c *Client) CheckServers(datacenter string, fn func(*metadata.Server) bool)
return
}
c.routers.CheckServers(fn)
c.router.CheckServers(datacenter, fn)
}
type serversACLMode struct {

3
agent/router/manager.go
View File

@ -254,6 +254,9 @@ func (m *Manager) CheckServers(fn func(srv *metadata.Server) bool) {
// getServerList is a convenience method which hides the locking semantics
// of atomic.Value from the caller.
func (m *Manager) getServerList() serverList {
if m == nil {
return serverList{}
}
return m.listValue.Load().(serverList)
}

97
agent/router/router.go
View File

@ -144,6 +144,12 @@ func (r *Router) AddArea(areaID types.AreaID, cluster RouterSerfCluster, pinger
}
r.areas[areaID] = area
// always ensure we have a started manager for the LAN area
if areaID == types.AreaLAN {
r.logger.Info("Initializing LAN area manager")
r.maybeInitializeManager(area, r.localDatacenter)
}
// Do an initial populate of the manager so that we don't have to wait
// for events to fire. This lets us attempt to use all the known servers
// initially, and then will quickly detect that they are failed if we
@ -151,10 +157,12 @@ func (r *Router) AddArea(areaID types.AreaID, cluster RouterSerfCluster, pinger
for _, m := range cluster.Members() {
ok, parts := metadata.IsConsulServer(m)
if !ok {
r.logger.Warn("Non-server in server-only area",
"non_server", m.Name,
"area", areaID,
)
if areaID != types.AreaLAN {
r.logger.Warn("Non-server in server-only area",
"non_server", m.Name,
"area", areaID,
)
}
continue
}
@ -233,24 +241,35 @@ func (r *Router) RemoveArea(areaID types.AreaID) error {
return nil
}
// maybeInitializeManager will initialize a new manager for the given area/dc
// if its not already created. Calling this function should only be done if
// holding a write lock on the Router.
func (r *Router) maybeInitializeManager(area *areaInfo, dc string) *Manager {
info, ok := area.managers[dc]
if ok {
return info.manager
}
shutdownCh := make(chan struct{})
manager := New(r.logger, shutdownCh, area.cluster, area.pinger, r.serverName)
info = &managerInfo{
manager: manager,
shutdownCh: shutdownCh,
}
area.managers[dc] = info
managers := r.managers[dc]
r.managers[dc] = append(managers, manager)
go manager.Start()
return manager
}
// addServer does the work of AddServer once the write lock is held.
func (r *Router) addServer(area *areaInfo, s *metadata.Server) error {
// Make the manager on the fly if this is the first we've seen of it,
// and add it to the index.
info, ok := area.managers[s.Datacenter]
if !ok {
shutdownCh := make(chan struct{})
manager := New(r.logger, shutdownCh, area.cluster, area.pinger, r.serverName)
info = &managerInfo{
manager: manager,
shutdownCh: shutdownCh,
}
area.managers[s.Datacenter] = info
managers := r.managers[s.Datacenter]
r.managers[s.Datacenter] = append(managers, manager)
go manager.Start()
}
manager := r.maybeInitializeManager(area, s.Datacenter)
// If TLS is enabled for the area, set it on the server so the manager
// knows to use TLS when pinging it.
@ -258,7 +277,7 @@ func (r *Router) addServer(area *areaInfo, s *metadata.Server) error {
s.UseTLS = true
}
info.manager.AddServer(s)
manager.AddServer(s)
return nil
}
@ -341,6 +360,28 @@ func (r *Router) FindRoute(datacenter string) (*Manager, *metadata.Server, bool)
return r.routeFn(datacenter)
}
// FindLANRoute returns a healthy server within the local datacenter. In some
// cases this may return a best-effort unhealthy server that can be used for a
// connection attempt. If any problem occurs with the given server, the caller
// should feed that back to the manager associated with the server, which is
// also returned, by calling NotifyFailedServer().
func (r *Router) FindLANRoute() (*Manager, *metadata.Server) {
mgr := r.GetLANManager()
if mgr == nil {
return nil, nil
}
return mgr, mgr.FindServer()
}
// FindLANServer will look for a server in the local datacenter.
// This function may return a nil value if no server is available.
func (r *Router) FindLANServer() *metadata.Server {
_, srv := r.FindLANRoute()
return srv
}
// findDirectRoute looks for a route to the given datacenter if it's directly
// adjacent to the server.
func (r *Router) findDirectRoute(datacenter string) (*Manager, *metadata.Server, bool) {
@ -432,6 +473,24 @@ func (r *Router) HasDatacenter(dc string) bool {
return ok
}
// GetLANManager returns the Manager for the LAN area and the local datacenter
func (r *Router) GetLANManager() *Manager {
r.RLock()
defer r.RUnlock()
area, ok := r.areas[types.AreaLAN]
if !ok {
return nil
}
managerInfo, ok := area.managers[r.localDatacenter]
if !ok {
return nil
}
return managerInfo.manager
}
// datacenterSorter takes a list of DC names and a parallel vector of distances
// and implements sort.Interface, keeping both structures coherent and sorting
// by distance.

41
agent/router/router_test.go
View File

@ -15,6 +15,8 @@ import (
"github.com/hashicorp/consul/types"
"github.com/hashicorp/serf/coordinate"
"github.com/hashicorp/serf/serf"
"github.com/stretchr/testify/require"
)
type mockCluster struct {
@ -69,6 +71,26 @@ func (m *mockCluster) AddMember(dc string, name string, coord *coordinate.Coordi
m.addr++
}
func (m *mockCluster) AddLANMember(dc, name, role string, coord *coordinate.Coordinate) {
member := serf.Member{
Name: name,
Addr: net.ParseIP(fmt.Sprintf("127.0.0.%d", m.addr)),
Port: 8300,
Tags: map[string]string{
"dc": dc,
"role": role,
"port": "8300",
"build": "0.8.0",
"vsn": "3",
},
}
m.members = append(m.members, member)
if coord != nil {
m.coords[member.Name] = coord
}
m.addr++
}
// testCluster is used to generate a single WAN-like area with a known set of
// member and RTT topology.
//
@ -487,3 +509,22 @@ func TestRouter_GetDatacenterMaps(t *testing.T) {
}
}
}
func TestRouter_FindLANServer(t *testing.T) {
r := testRouter(t, "dc0")
lan := newMockCluster("node4.dc0")
lan.AddLANMember("dc0", "node0", "consul", lib.GenerateCoordinate(10*time.Millisecond))
lan.AddLANMember("dc0", "node1", "", lib.GenerateCoordinate(20*time.Millisecond))
lan.AddLANMember("dc0", "node2", "", lib.GenerateCoordinate(21*time.Millisecond))
require.NoError(t, r.AddArea(types.AreaLAN, lan, &fauxConnPool{}))
srv := r.FindLANServer()
require.NotNil(t, srv)
require.Equal(t, "127.0.0.1:8300", srv.Addr.String())
mgr, srv2 := r.FindLANRoute()
require.NotNil(t, mgr)
require.Equal(t, srv, srv2)
}

4
agent/setup.go
View File

@ -13,6 +13,7 @@ import (
certmon "github.com/hashicorp/consul/agent/cert-monitor"
"github.com/hashicorp/consul/agent/config"
"github.com/hashicorp/consul/agent/pool"
"github.com/hashicorp/consul/agent/router"
"github.com/hashicorp/consul/agent/structs"
"github.com/hashicorp/consul/agent/token"
"github.com/hashicorp/consul/ipaddr"
@ -35,6 +36,7 @@ type BaseDeps struct {
Cache *cache.Cache
AutoConfig *autoconf.AutoConfig // TODO: use an interface
ConnPool *pool.ConnPool // TODO: use an interface
Router *router.Router
}
// MetricsHandler provides an http.Handler for displaying metrics.
@ -86,6 +88,8 @@ func NewBaseDeps(configLoader ConfigLoader, logOut io.Writer) (BaseDeps, error)
deferredAC := &deferredAutoConfig{}
d.Router = router.NewRouter(d.Logger, cfg.Datacenter, fmt.Sprintf("%s.%s", cfg.NodeName, cfg.Datacenter))
cmConf := new(certmon.Config).
WithCache(d.Cache).
WithTLSConfigurator(d.TLSConfigurator).

4
types/area.go
View File

@ -7,3 +7,7 @@ type AreaID string
// This represents the existing WAN area that's built in to Consul. Consul
// Enterprise generalizes areas, which are represented with UUIDs.
const AreaWAN AreaID = "wan"
// This represents the existing LAN area that's built in to Consul. Consul
// Enterprise generalizes areas, which are represented with UUIDs.
const AreaLAN AreaID = "lan"