open-consul/agent/xds/endpoints.go
Chris S. Kim c752c5bff2
Update envoy metrics label extraction for peered clusters and listeners (#13818)
Now that peered upstreams can generate envoy resources (#13758), we need a way to disambiguate local from peered resources in our metrics. The key difference is that datacenter and partition will be replaced with peer, since in the context of peered resources partition is ambiguous (could refer to the partition in a remote cluster or one that exists locally). The partition and datacenter of the proxy will always be that of the source service.

Regexes were updated to make emitting datacenter and partition labels mutually exclusive with peer labels.

Listener filter names were updated to better match the existing regex.

Cluster names assigned to peered upstreams were updated to be synthesized from local peer name (it previously used the externally provided primary SNI, which contained the peer name from the other side of the peering). Integration tests were updated to assert for the new peer labels.
2022-07-25 13:49:00 -04:00

757 lines
23 KiB
Go

package xds
import (
"errors"
"fmt"
envoy_cluster_v3 "github.com/envoyproxy/go-control-plane/envoy/config/cluster/v3"
envoy_core_v3 "github.com/envoyproxy/go-control-plane/envoy/config/core/v3"
envoy_endpoint_v3 "github.com/envoyproxy/go-control-plane/envoy/config/endpoint/v3"
"github.com/golang/protobuf/proto"
bexpr "github.com/hashicorp/go-bexpr"
"github.com/hashicorp/consul/agent/connect"
"github.com/hashicorp/consul/agent/proxycfg"
"github.com/hashicorp/consul/agent/structs"
"github.com/hashicorp/consul/api"
)
const (
UnnamedSubset = ""
)
// endpointsFromSnapshot returns the xDS API representation of the "endpoints"
func (s *ResourceGenerator) endpointsFromSnapshot(cfgSnap *proxycfg.ConfigSnapshot) ([]proto.Message, error) {
if cfgSnap == nil {
return nil, errors.New("nil config given")
}
switch cfgSnap.Kind {
case structs.ServiceKindConnectProxy:
return s.endpointsFromSnapshotConnectProxy(cfgSnap)
case structs.ServiceKindTerminatingGateway:
return s.endpointsFromSnapshotTerminatingGateway(cfgSnap)
case structs.ServiceKindMeshGateway:
return s.endpointsFromSnapshotMeshGateway(cfgSnap)
case structs.ServiceKindIngressGateway:
return s.endpointsFromSnapshotIngressGateway(cfgSnap)
default:
return nil, fmt.Errorf("Invalid service kind: %v", cfgSnap.Kind)
}
}
// endpointsFromSnapshotConnectProxy returns the xDS API representation of the "endpoints"
// (upstream instances) in the snapshot.
func (s *ResourceGenerator) endpointsFromSnapshotConnectProxy(cfgSnap *proxycfg.ConfigSnapshot) ([]proto.Message, error) {
// TODO: this estimate is wrong
resources := make([]proto.Message, 0,
len(cfgSnap.ConnectProxy.PreparedQueryEndpoints)+
cfgSnap.ConnectProxy.PeerUpstreamEndpoints.Len()+
len(cfgSnap.ConnectProxy.WatchedUpstreamEndpoints))
// NOTE: Any time we skip a chain below we MUST also skip that discovery chain in clusters.go
// so that the sets of endpoints generated matches the sets of clusters.
for uid, chain := range cfgSnap.ConnectProxy.DiscoveryChain {
upstream := cfgSnap.ConnectProxy.UpstreamConfig[uid]
explicit := upstream.HasLocalPortOrSocket()
implicit := cfgSnap.ConnectProxy.IsImplicitUpstream(uid)
if !implicit && !explicit {
// Discovery chain is not associated with a known explicit or implicit upstream so it is skipped.
continue
}
var upstreamConfigMap map[string]interface{}
if upstream != nil {
upstreamConfigMap = upstream.Config
}
es, err := s.endpointsFromDiscoveryChain(
uid,
chain,
cfgSnap.Locality,
upstreamConfigMap,
cfgSnap.ConnectProxy.WatchedUpstreamEndpoints[uid],
cfgSnap.ConnectProxy.WatchedGatewayEndpoints[uid],
false,
)
if err != nil {
return nil, err
}
resources = append(resources, es...)
}
// NOTE: Any time we skip an upstream below we MUST also skip that same
// upstream in clusters.go so that the sets of endpoints generated matches
// the sets of clusters.
for _, uid := range cfgSnap.ConnectProxy.PeeredUpstreamIDs() {
upstreamCfg := cfgSnap.ConnectProxy.UpstreamConfig[uid]
explicit := upstreamCfg.HasLocalPortOrSocket()
implicit := cfgSnap.ConnectProxy.IsImplicitUpstream(uid)
if !implicit && !explicit {
// Not associated with a known explicit or implicit upstream so it is skipped.
continue
}
tbs, ok := cfgSnap.ConnectProxy.UpstreamPeerTrustBundles.Get(uid.Peer)
if !ok {
// this should never happen since we loop through upstreams with
// set trust bundles
return nil, fmt.Errorf("trust bundle not ready for peer %s", uid.Peer)
}
clusterName := generatePeeredClusterName(uid, tbs)
// Also skip peer instances with a hostname as their address. EDS
// cannot resolve hostnames, so we provide them through CDS instead.
if _, ok := cfgSnap.ConnectProxy.PeerUpstreamEndpointsUseHostnames[uid]; ok {
continue
}
endpoints, ok := cfgSnap.ConnectProxy.PeerUpstreamEndpoints.Get(uid)
if ok {
la := makeLoadAssignment(
clusterName,
[]loadAssignmentEndpointGroup{
{Endpoints: endpoints},
},
proxycfg.GatewayKey{ /*empty so it never matches*/ },
)
resources = append(resources, la)
}
}
// Looping over explicit upstreams is only needed for prepared queries because they do not have discovery chains
for _, u := range cfgSnap.Proxy.Upstreams {
if u.DestinationType != structs.UpstreamDestTypePreparedQuery {
continue
}
uid := proxycfg.NewUpstreamID(&u)
dc := u.Datacenter
if dc == "" {
dc = cfgSnap.Datacenter
}
clusterName := connect.UpstreamSNI(&u, "", dc, cfgSnap.Roots.TrustDomain)
endpoints, ok := cfgSnap.ConnectProxy.PreparedQueryEndpoints[uid]
if ok {
la := makeLoadAssignment(
clusterName,
[]loadAssignmentEndpointGroup{
{Endpoints: endpoints},
},
cfgSnap.Locality,
)
resources = append(resources, la)
}
}
// Loop over potential destinations in the mesh, then grab the gateway nodes associated with each
cfgSnap.ConnectProxy.DestinationsUpstream.ForEachKey(func(uid proxycfg.UpstreamID) bool {
svcConfig, ok := cfgSnap.ConnectProxy.DestinationsUpstream.Get(uid)
if !ok || svcConfig.Destination == nil {
return true
}
for _, address := range svcConfig.Destination.Addresses {
name := clusterNameForDestination(cfgSnap, uid.Name, address, uid.NamespaceOrDefault(), uid.PartitionOrDefault())
endpoints, ok := cfgSnap.ConnectProxy.DestinationGateways.Get(uid)
if ok {
la := makeLoadAssignment(
name,
[]loadAssignmentEndpointGroup{
{Endpoints: endpoints},
},
proxycfg.GatewayKey{ /*empty so it never matches*/ },
)
resources = append(resources, la)
}
}
return true
})
return resources, nil
}
func (s *ResourceGenerator) filterSubsetEndpoints(subset *structs.ServiceResolverSubset, endpoints structs.CheckServiceNodes) (structs.CheckServiceNodes, error) {
// locally execute the subsets filter
if subset.Filter != "" {
filter, err := bexpr.CreateFilter(subset.Filter, nil, endpoints)
if err != nil {
return nil, err
}
raw, err := filter.Execute(endpoints)
if err != nil {
return nil, err
}
return raw.(structs.CheckServiceNodes), nil
}
return endpoints, nil
}
func (s *ResourceGenerator) endpointsFromSnapshotTerminatingGateway(cfgSnap *proxycfg.ConfigSnapshot) ([]proto.Message, error) {
return s.endpointsFromServicesAndResolvers(cfgSnap, cfgSnap.TerminatingGateway.ServiceGroups, cfgSnap.TerminatingGateway.ServiceResolvers)
}
func (s *ResourceGenerator) endpointsFromSnapshotMeshGateway(cfgSnap *proxycfg.ConfigSnapshot) ([]proto.Message, error) {
keys := cfgSnap.MeshGateway.GatewayKeys()
resources := make([]proto.Message, 0, len(keys)+len(cfgSnap.MeshGateway.ServiceGroups))
for _, key := range keys {
if key.Matches(cfgSnap.Datacenter, cfgSnap.ProxyID.PartitionOrDefault()) {
continue // skip local
}
// Also skip gateways with a hostname as their address. EDS cannot resolve hostnames,
// so we provide them through CDS instead.
if len(cfgSnap.MeshGateway.HostnameDatacenters[key.String()]) > 0 {
continue
}
endpoints := cfgSnap.GetMeshGatewayEndpoints(key)
if len(endpoints) == 0 {
s.Logger.Error("skipping mesh gateway endpoints because no definition found", "datacenter", key)
continue
}
{ // standard connect
clusterName := connect.GatewaySNI(key.Datacenter, key.Partition, cfgSnap.Roots.TrustDomain)
la := makeLoadAssignment(
clusterName,
[]loadAssignmentEndpointGroup{
{Endpoints: endpoints},
},
cfgSnap.Locality,
)
resources = append(resources, la)
}
if cfgSnap.ProxyID.InDefaultPartition() &&
cfgSnap.ServiceMeta[structs.MetaWANFederationKey] == "1" &&
cfgSnap.ServerSNIFn != nil {
clusterName := cfgSnap.ServerSNIFn(key.Datacenter, "")
la := makeLoadAssignment(
clusterName,
[]loadAssignmentEndpointGroup{
{Endpoints: endpoints},
},
cfgSnap.Locality,
)
resources = append(resources, la)
}
}
// generate endpoints for our servers if WAN federation is enabled
if cfgSnap.ProxyID.InDefaultPartition() &&
cfgSnap.ServiceMeta[structs.MetaWANFederationKey] == "1" &&
cfgSnap.ServerSNIFn != nil {
var allServersLbEndpoints []*envoy_endpoint_v3.LbEndpoint
for _, srv := range cfgSnap.MeshGateway.ConsulServers {
clusterName := cfgSnap.ServerSNIFn(cfgSnap.Datacenter, srv.Node.Node)
_, addr, port := srv.BestAddress(false /*wan*/)
lbEndpoint := &envoy_endpoint_v3.LbEndpoint{
HostIdentifier: &envoy_endpoint_v3.LbEndpoint_Endpoint{
Endpoint: &envoy_endpoint_v3.Endpoint{
Address: makeAddress(addr, port),
},
},
HealthStatus: envoy_core_v3.HealthStatus_UNKNOWN,
}
cla := &envoy_endpoint_v3.ClusterLoadAssignment{
ClusterName: clusterName,
Endpoints: []*envoy_endpoint_v3.LocalityLbEndpoints{{
LbEndpoints: []*envoy_endpoint_v3.LbEndpoint{lbEndpoint},
}},
}
allServersLbEndpoints = append(allServersLbEndpoints, lbEndpoint)
resources = append(resources, cla)
}
// And add one catch all so that remote datacenters can dial ANY server
// in this datacenter without knowing its name.
resources = append(resources, &envoy_endpoint_v3.ClusterLoadAssignment{
ClusterName: cfgSnap.ServerSNIFn(cfgSnap.Datacenter, ""),
Endpoints: []*envoy_endpoint_v3.LocalityLbEndpoints{{
LbEndpoints: allServersLbEndpoints,
}},
})
}
// Generate the endpoints for each service and its subsets
e, err := s.endpointsFromServicesAndResolvers(cfgSnap, cfgSnap.MeshGateway.ServiceGroups, cfgSnap.MeshGateway.ServiceResolvers)
if err != nil {
return nil, err
}
resources = append(resources, e...)
// Generate the endpoints for exported discovery chain targets.
e, err = s.makeExportedUpstreamEndpointsForMeshGateway(cfgSnap)
if err != nil {
return nil, err
}
resources = append(resources, e...)
return resources, nil
}
func (s *ResourceGenerator) endpointsFromServicesAndResolvers(
cfgSnap *proxycfg.ConfigSnapshot,
services map[structs.ServiceName]structs.CheckServiceNodes,
resolvers map[structs.ServiceName]*structs.ServiceResolverConfigEntry,
) ([]proto.Message, error) {
resources := make([]proto.Message, 0, len(services))
// generate the endpoints for the linked service groups
for svc, endpoints := range services {
// Skip creating endpoints for services that have hostnames as addresses
// EDS cannot resolve hostnames so we provide them through CDS instead
if cfgSnap.Kind == structs.ServiceKindTerminatingGateway && len(cfgSnap.TerminatingGateway.HostnameServices[svc]) > 0 {
continue
}
clusterEndpoints := make(map[string][]loadAssignmentEndpointGroup)
clusterEndpoints[UnnamedSubset] = []loadAssignmentEndpointGroup{{Endpoints: endpoints, OnlyPassing: false}}
// Collect all of the loadAssignmentEndpointGroups for the various subsets. We do this before generating
// the endpoints for the default/unnamed subset so that we can take into account the DefaultSubset on the
// service-resolver which may prevent the default/unnamed cluster from creating endpoints for all service
// instances.
if resolver, hasResolver := resolvers[svc]; hasResolver {
for subsetName, subset := range resolver.Subsets {
subsetEndpoints, err := s.filterSubsetEndpoints(&subset, endpoints)
if err != nil {
return nil, err
}
groups := []loadAssignmentEndpointGroup{{Endpoints: subsetEndpoints, OnlyPassing: subset.OnlyPassing}}
clusterEndpoints[subsetName] = groups
// if this subset is the default then override the unnamed subset with this configuration
if subsetName == resolver.DefaultSubset {
clusterEndpoints[UnnamedSubset] = groups
}
}
}
// now generate the load assignment for all subsets
for subsetName, groups := range clusterEndpoints {
clusterName := connect.ServiceSNI(svc.Name, subsetName, svc.NamespaceOrDefault(), svc.PartitionOrDefault(), cfgSnap.Datacenter, cfgSnap.Roots.TrustDomain)
la := makeLoadAssignment(
clusterName,
groups,
cfgSnap.Locality,
)
resources = append(resources, la)
}
}
return resources, nil
}
func (s *ResourceGenerator) endpointsFromSnapshotIngressGateway(cfgSnap *proxycfg.ConfigSnapshot) ([]proto.Message, error) {
var resources []proto.Message
createdClusters := make(map[proxycfg.UpstreamID]bool)
for _, upstreams := range cfgSnap.IngressGateway.Upstreams {
for _, u := range upstreams {
uid := proxycfg.NewUpstreamID(&u)
// If we've already created endpoints for this upstream, skip it. Multiple listeners may
// reference the same upstream, so we don't need to create duplicate endpoints in that case.
if createdClusters[uid] {
continue
}
es, err := s.endpointsFromDiscoveryChain(
uid,
cfgSnap.IngressGateway.DiscoveryChain[uid],
proxycfg.GatewayKey{Datacenter: cfgSnap.Datacenter, Partition: u.DestinationPartition},
u.Config,
cfgSnap.IngressGateway.WatchedUpstreamEndpoints[uid],
cfgSnap.IngressGateway.WatchedGatewayEndpoints[uid],
false,
)
if err != nil {
return nil, err
}
resources = append(resources, es...)
createdClusters[uid] = true
}
}
return resources, nil
}
// used in clusters.go
func makeEndpoint(host string, port int) *envoy_endpoint_v3.LbEndpoint {
return &envoy_endpoint_v3.LbEndpoint{
HostIdentifier: &envoy_endpoint_v3.LbEndpoint_Endpoint{
Endpoint: &envoy_endpoint_v3.Endpoint{
Address: makeAddress(host, port),
},
},
}
}
func makePipeEndpoint(path string) *envoy_endpoint_v3.LbEndpoint {
return &envoy_endpoint_v3.LbEndpoint{
HostIdentifier: &envoy_endpoint_v3.LbEndpoint_Endpoint{
Endpoint: &envoy_endpoint_v3.Endpoint{
Address: makePipeAddress(path, 0),
},
},
}
}
func (s *ResourceGenerator) endpointsFromDiscoveryChain(
uid proxycfg.UpstreamID,
chain *structs.CompiledDiscoveryChain,
gatewayKey proxycfg.GatewayKey,
upstreamConfigMap map[string]interface{},
upstreamEndpoints map[string]structs.CheckServiceNodes,
gatewayEndpoints map[string]structs.CheckServiceNodes,
forMeshGateway bool,
) ([]proto.Message, error) {
if chain == nil {
if forMeshGateway {
return nil, fmt.Errorf("missing discovery chain for %s", uid)
}
return nil, nil
}
if upstreamConfigMap == nil {
upstreamConfigMap = make(map[string]interface{}) // TODO:needed?
}
var resources []proto.Message
var escapeHatchCluster *envoy_cluster_v3.Cluster
if !forMeshGateway {
cfg, err := structs.ParseUpstreamConfigNoDefaults(upstreamConfigMap)
if err != nil {
// Don't hard fail on a config typo, just warn. The parse func returns
// default config if there is an error so it's safe to continue.
s.Logger.Warn("failed to parse", "upstream", uid,
"error", err)
}
if cfg.EnvoyClusterJSON != "" {
if chain.Default {
// If you haven't done anything to setup the discovery chain, then
// you can use the envoy_cluster_json escape hatch.
escapeHatchCluster, err = makeClusterFromUserConfig(cfg.EnvoyClusterJSON)
if err != nil {
return resources, nil
}
} else {
s.Logger.Warn("ignoring escape hatch setting, because a discovery chain is configued for",
"discovery chain", chain.ServiceName, "upstream", uid,
"envoy_cluster_json", chain.ServiceName)
}
}
}
// Find all resolver nodes.
for _, node := range chain.Nodes {
if node.Type != structs.DiscoveryGraphNodeTypeResolver {
continue
}
failover := node.Resolver.Failover
targetID := node.Resolver.Target
target := chain.Targets[targetID]
clusterName := CustomizeClusterName(target.Name, chain)
if escapeHatchCluster != nil {
clusterName = escapeHatchCluster.Name
}
if forMeshGateway {
clusterName = meshGatewayExportedClusterNamePrefix + clusterName
}
s.Logger.Debug("generating endpoints for", "cluster", clusterName)
// Determine if we have to generate the entire cluster differently.
failoverThroughMeshGateway := chain.WillFailoverThroughMeshGateway(node) && !forMeshGateway
if failoverThroughMeshGateway {
actualTargetID := firstHealthyTarget(
chain.Targets,
upstreamEndpoints,
targetID,
failover.Targets,
)
if actualTargetID != targetID {
targetID = actualTargetID
}
failover = nil
}
primaryGroup, valid := makeLoadAssignmentEndpointGroup(
chain.Targets,
upstreamEndpoints,
gatewayEndpoints,
targetID,
gatewayKey,
forMeshGateway,
)
if !valid {
continue // skip the cluster if we're still populating the snapshot
}
var numFailoverTargets int
if failover != nil {
numFailoverTargets = len(failover.Targets)
}
endpointGroups := make([]loadAssignmentEndpointGroup, 0, numFailoverTargets+1)
endpointGroups = append(endpointGroups, primaryGroup)
if failover != nil && len(failover.Targets) > 0 {
for _, failTargetID := range failover.Targets {
failoverGroup, valid := makeLoadAssignmentEndpointGroup(
chain.Targets,
upstreamEndpoints,
gatewayEndpoints,
failTargetID,
gatewayKey,
forMeshGateway,
)
if !valid {
continue // skip the failover target if we're still populating the snapshot
}
endpointGroups = append(endpointGroups, failoverGroup)
}
}
la := makeLoadAssignment(
clusterName,
endpointGroups,
gatewayKey,
)
resources = append(resources, la)
}
return resources, nil
}
func (s *ResourceGenerator) makeExportedUpstreamEndpointsForMeshGateway(cfgSnap *proxycfg.ConfigSnapshot) ([]proto.Message, error) {
var resources []proto.Message
populatedExportedClusters := make(map[string]struct{}) // key=clusterName
for _, svc := range cfgSnap.MeshGatewayValidExportedServices() {
chain := cfgSnap.MeshGateway.DiscoveryChain[svc]
chainEndpoints := make(map[string]structs.CheckServiceNodes)
for _, target := range chain.Targets {
if !cfgSnap.Locality.Matches(target.Datacenter, target.Partition) {
s.Logger.Warn("ignoring discovery chain target that crosses a datacenter or partition boundary in a mesh gateway",
"target", target,
"gatewayLocality", cfgSnap.Locality,
)
continue
}
targetSvc := target.ServiceName()
endpoints, ok := cfgSnap.MeshGateway.ServiceGroups[targetSvc]
if !ok {
continue // ignore; not ready
}
if target.ServiceSubset == "" {
chainEndpoints[target.ID] = endpoints
} else {
resolver, ok := cfgSnap.MeshGateway.ServiceResolvers[targetSvc]
if !ok {
continue // ignore; not ready
}
subset, ok := resolver.Subsets[target.ServiceSubset]
if !ok {
continue // ignore; not ready
}
subsetEndpoints, err := s.filterSubsetEndpoints(&subset, endpoints)
if err != nil {
return nil, err
}
chainEndpoints[target.ID] = subsetEndpoints
}
}
clusterEndpoints, err := s.endpointsFromDiscoveryChain(
proxycfg.NewUpstreamIDFromServiceName(svc),
chain,
cfgSnap.Locality,
nil,
chainEndpoints,
nil,
true,
)
if err != nil {
return nil, err
}
for _, endpoints := range clusterEndpoints {
clusterName := getResourceName(endpoints)
if _, ok := populatedExportedClusters[clusterName]; ok {
continue
}
populatedExportedClusters[clusterName] = struct{}{}
resources = append(resources, endpoints)
}
}
return resources, nil
}
type loadAssignmentEndpointGroup struct {
Endpoints structs.CheckServiceNodes
OnlyPassing bool
OverrideHealth envoy_core_v3.HealthStatus
}
func makeLoadAssignment(clusterName string, endpointGroups []loadAssignmentEndpointGroup, localKey proxycfg.GatewayKey) *envoy_endpoint_v3.ClusterLoadAssignment {
cla := &envoy_endpoint_v3.ClusterLoadAssignment{
ClusterName: clusterName,
Endpoints: make([]*envoy_endpoint_v3.LocalityLbEndpoints, 0, len(endpointGroups)),
}
if len(endpointGroups) > 1 {
cla.Policy = &envoy_endpoint_v3.ClusterLoadAssignment_Policy{
// We choose such a large value here that the failover math should
// in effect not happen until zero instances are healthy.
OverprovisioningFactor: makeUint32Value(100000),
}
}
for priority, endpointGroup := range endpointGroups {
endpoints := endpointGroup.Endpoints
es := make([]*envoy_endpoint_v3.LbEndpoint, 0, len(endpoints))
for _, ep := range endpoints {
// TODO (mesh-gateway) - should we respect the translate_wan_addrs configuration here or just always use the wan for cross-dc?
_, addr, port := ep.BestAddress(!localKey.Matches(ep.Node.Datacenter, ep.Node.PartitionOrDefault()))
healthStatus, weight := calculateEndpointHealthAndWeight(ep, endpointGroup.OnlyPassing)
if endpointGroup.OverrideHealth != envoy_core_v3.HealthStatus_UNKNOWN {
healthStatus = endpointGroup.OverrideHealth
}
es = append(es, &envoy_endpoint_v3.LbEndpoint{
HostIdentifier: &envoy_endpoint_v3.LbEndpoint_Endpoint{
Endpoint: &envoy_endpoint_v3.Endpoint{
Address: makeAddress(addr, port),
},
},
HealthStatus: healthStatus,
LoadBalancingWeight: makeUint32Value(weight),
})
}
cla.Endpoints = append(cla.Endpoints, &envoy_endpoint_v3.LocalityLbEndpoints{
Priority: uint32(priority),
LbEndpoints: es,
})
}
return cla
}
func makeLoadAssignmentEndpointGroup(
targets map[string]*structs.DiscoveryTarget,
targetHealth map[string]structs.CheckServiceNodes,
gatewayHealth map[string]structs.CheckServiceNodes,
targetID string,
localKey proxycfg.GatewayKey,
forMeshGateway bool,
) (loadAssignmentEndpointGroup, bool) {
realEndpoints, ok := targetHealth[targetID]
if !ok {
// skip the cluster if we're still populating the snapshot
return loadAssignmentEndpointGroup{}, false
}
target := targets[targetID]
var gatewayKey proxycfg.GatewayKey
switch target.MeshGateway.Mode {
case structs.MeshGatewayModeRemote:
gatewayKey.Datacenter = target.Datacenter
gatewayKey.Partition = target.Partition
case structs.MeshGatewayModeLocal:
gatewayKey = localKey
}
if forMeshGateway || gatewayKey.IsEmpty() || localKey.Matches(target.Datacenter, target.Partition) {
// Gateways are not needed if the request isn't for a remote DC or partition.
return loadAssignmentEndpointGroup{
Endpoints: realEndpoints,
OnlyPassing: target.Subset.OnlyPassing,
}, true
}
// If using a mesh gateway we need to pull those endpoints instead.
gatewayEndpoints, ok := gatewayHealth[gatewayKey.String()]
if !ok {
// skip the cluster if we're still populating the snapshot
return loadAssignmentEndpointGroup{}, false
}
// But we will use the health from the actual backend service.
overallHealth := envoy_core_v3.HealthStatus_UNHEALTHY
for _, ep := range realEndpoints {
health, _ := calculateEndpointHealthAndWeight(ep, target.Subset.OnlyPassing)
if health == envoy_core_v3.HealthStatus_HEALTHY {
overallHealth = envoy_core_v3.HealthStatus_HEALTHY
break
}
}
return loadAssignmentEndpointGroup{
Endpoints: gatewayEndpoints,
OverrideHealth: overallHealth,
}, true
}
func calculateEndpointHealthAndWeight(
ep structs.CheckServiceNode,
onlyPassing bool,
) (envoy_core_v3.HealthStatus, int) {
healthStatus := envoy_core_v3.HealthStatus_HEALTHY
weight := 1
if ep.Service.Weights != nil {
weight = ep.Service.Weights.Passing
}
for _, chk := range ep.Checks {
if chk.Status == api.HealthCritical {
healthStatus = envoy_core_v3.HealthStatus_UNHEALTHY
}
if onlyPassing && chk.Status != api.HealthPassing {
healthStatus = envoy_core_v3.HealthStatus_UNHEALTHY
}
if chk.Status == api.HealthWarning && ep.Service.Weights != nil {
weight = ep.Service.Weights.Warning
}
}
// Make weights fit Envoy's limits. A zero weight means that either Warning
// (likely) or Passing (weirdly) weight has been set to 0 effectively making
// this instance unhealthy and should not be sent traffic.
if weight < 1 {
healthStatus = envoy_core_v3.HealthStatus_UNHEALTHY
weight = 1
}
if weight > 128 {
weight = 128
}
return healthStatus, weight
}