consul/agent/xds/clusters.go

380 lines
12 KiB
Go

package xds
import (
"encoding/json"
"errors"
"fmt"
"time"
envoy "github.com/envoyproxy/go-control-plane/envoy/api/v2"
envoyauth "github.com/envoyproxy/go-control-plane/envoy/api/v2/auth"
envoycluster "github.com/envoyproxy/go-control-plane/envoy/api/v2/cluster"
envoycore "github.com/envoyproxy/go-control-plane/envoy/api/v2/core"
envoyendpoint "github.com/envoyproxy/go-control-plane/envoy/api/v2/endpoint"
envoytype "github.com/envoyproxy/go-control-plane/envoy/type"
"github.com/gogo/protobuf/jsonpb"
"github.com/gogo/protobuf/proto"
"github.com/gogo/protobuf/types"
"github.com/hashicorp/consul/agent/proxycfg"
"github.com/hashicorp/consul/agent/structs"
)
// clustersFromSnapshot returns the xDS API representation of the "clusters" in the snapshot.
func (s *Server) clustersFromSnapshot(cfgSnap *proxycfg.ConfigSnapshot, token string) ([]proto.Message, error) {
if cfgSnap == nil {
return nil, errors.New("nil config given")
}
switch cfgSnap.Kind {
case structs.ServiceKindConnectProxy:
return s.clustersFromSnapshotConnectProxy(cfgSnap, token)
case structs.ServiceKindMeshGateway:
return s.clustersFromSnapshotMeshGateway(cfgSnap, token)
default:
return nil, fmt.Errorf("Invalid service kind: %v", cfgSnap.Kind)
}
}
// clustersFromSnapshot returns the xDS API representation of the "clusters"
// (upstreams) in the snapshot.
func (s *Server) clustersFromSnapshotConnectProxy(cfgSnap *proxycfg.ConfigSnapshot, token string) ([]proto.Message, error) {
// TODO(rb): this sizing is a low bound.
clusters := make([]proto.Message, len(cfgSnap.Proxy.Upstreams)+1)
// Include the "app" cluster for the public listener
appCluster, err := s.makeAppCluster(cfgSnap)
if err != nil {
return nil, err
}
clusters = append(clusters, appCluster)
for _, u := range cfgSnap.Proxy.Upstreams {
id := u.Identifier()
var chain *structs.CompiledDiscoveryChain
if u.DestinationType != structs.UpstreamDestTypePreparedQuery {
chain = cfgSnap.ConnectProxy.DiscoveryChain[id]
}
if chain == nil || chain.IsDefault() {
// Either old-school upstream or prepared query.
upstreamCluster, err := s.makeUpstreamCluster(u, cfgSnap)
if err != nil {
return nil, err
}
clusters = append(clusters, upstreamCluster)
} else {
upstreamClusters, err := s.makeUpstreamClustersForDiscoveryChain(id, chain, cfgSnap)
if err != nil {
return nil, err
}
for _, cluster := range upstreamClusters {
clusters = append(clusters, cluster)
}
}
}
return clusters, nil
}
// clustersFromSnapshotMeshGateway returns the xDS API representation of the "clusters"
// for a mesh gateway. This will include 1 cluster per remote datacenter as well as
// 1 cluster for each service subset.
func (s *Server) clustersFromSnapshotMeshGateway(cfgSnap *proxycfg.ConfigSnapshot, token string) ([]proto.Message, error) {
// 1 cluster per remote dc + 1 cluster per local service (this is a lower bound - all subset specific clusters will be appended)
clusters := make([]proto.Message, 0, len(cfgSnap.MeshGateway.GatewayGroups)+len(cfgSnap.MeshGateway.ServiceGroups))
// generate the remote dc clusters
for dc, _ := range cfgSnap.MeshGateway.GatewayGroups {
clusterName := DatacenterSNI(dc, cfgSnap)
cluster, err := s.makeMeshGatewayCluster(clusterName, cfgSnap)
if err != nil {
return nil, err
}
clusters = append(clusters, cluster)
}
// generate the per-service clusters
for svc, _ := range cfgSnap.MeshGateway.ServiceGroups {
clusterName := ServiceSNI(svc, "", "default", cfgSnap.Datacenter, cfgSnap)
cluster, err := s.makeMeshGatewayCluster(clusterName, cfgSnap)
if err != nil {
return nil, err
}
clusters = append(clusters, cluster)
}
// generate the service subset clusters
for svc, resolver := range cfgSnap.MeshGateway.ServiceResolvers {
for subsetName, _ := range resolver.Subsets {
clusterName := ServiceSNI(svc, subsetName, "default", cfgSnap.Datacenter, cfgSnap)
cluster, err := s.makeMeshGatewayCluster(clusterName, cfgSnap)
if err != nil {
return nil, err
}
clusters = append(clusters, cluster)
}
}
return clusters, nil
}
func (s *Server) makeAppCluster(cfgSnap *proxycfg.ConfigSnapshot) (*envoy.Cluster, error) {
var c *envoy.Cluster
var err error
cfg, err := ParseProxyConfig(cfgSnap.Proxy.Config)
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.Printf("[WARN] envoy: failed to parse Connect.Proxy.Config: %s", err)
}
// If we have overridden local cluster config try to parse it into an Envoy cluster
if cfg.LocalClusterJSON != "" {
return makeClusterFromUserConfig(cfg.LocalClusterJSON)
}
if c == nil {
addr := cfgSnap.Proxy.LocalServiceAddress
if addr == "" {
addr = "127.0.0.1"
}
c = &envoy.Cluster{
Name: LocalAppClusterName,
ConnectTimeout: time.Duration(cfg.LocalConnectTimeoutMs) * time.Millisecond,
ClusterDiscoveryType: &envoy.Cluster_Type{Type: envoy.Cluster_STATIC},
LoadAssignment: &envoy.ClusterLoadAssignment{
ClusterName: LocalAppClusterName,
Endpoints: []envoyendpoint.LocalityLbEndpoints{
{
LbEndpoints: []envoyendpoint.LbEndpoint{
makeEndpoint(LocalAppClusterName,
addr,
cfgSnap.Proxy.LocalServicePort),
},
},
},
},
}
if cfg.Protocol == "http2" || cfg.Protocol == "grpc" {
c.Http2ProtocolOptions = &envoycore.Http2ProtocolOptions{}
}
}
return c, err
}
func (s *Server) makeUpstreamCluster(upstream structs.Upstream, cfgSnap *proxycfg.ConfigSnapshot) (*envoy.Cluster, error) {
var c *envoy.Cluster
var err error
ns := "default"
if upstream.DestinationNamespace != "" {
ns = upstream.DestinationNamespace
}
dc := cfgSnap.Datacenter
if upstream.Datacenter != "" {
dc = upstream.Datacenter
}
sni := ServiceSNI(upstream.DestinationName, "", ns, dc, cfgSnap)
cfg, err := ParseUpstreamConfig(upstream.Config)
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.Printf("[WARN] envoy: failed to parse Upstream[%s].Config: %s",
upstream.Identifier(), err)
}
if cfg.ClusterJSON != "" {
c, err = makeClusterFromUserConfig(cfg.ClusterJSON)
if err != nil {
return c, err
}
// In the happy path don't return yet as we need to inject TLS config still.
}
if c == nil {
c = &envoy.Cluster{
Name: upstream.Identifier(),
ConnectTimeout: time.Duration(cfg.ConnectTimeoutMs) * time.Millisecond,
ClusterDiscoveryType: &envoy.Cluster_Type{Type: envoy.Cluster_EDS},
EdsClusterConfig: &envoy.Cluster_EdsClusterConfig{
EdsConfig: &envoycore.ConfigSource{
ConfigSourceSpecifier: &envoycore.ConfigSource_Ads{
Ads: &envoycore.AggregatedConfigSource{},
},
},
},
// Having an empty config enables outlier detection with default config.
OutlierDetection: &envoycluster.OutlierDetection{},
}
if cfg.Protocol == "http2" || cfg.Protocol == "grpc" {
c.Http2ProtocolOptions = &envoycore.Http2ProtocolOptions{}
}
}
// Enable TLS upstream with the configured client certificate.
c.TlsContext = &envoyauth.UpstreamTlsContext{
CommonTlsContext: makeCommonTLSContext(cfgSnap),
Sni: sni,
}
return c, nil
}
func (s *Server) makeUpstreamClustersForDiscoveryChain(
upstreamID string,
chain *structs.CompiledDiscoveryChain,
cfgSnap *proxycfg.ConfigSnapshot,
) ([]*envoy.Cluster, error) {
if chain == nil {
panic("chain must be provided")
}
// TODO(rb): make escape hatches work with chains
var out []*envoy.Cluster
for target, node := range chain.GroupResolverNodes {
groupResolver := node.GroupResolver
// TODO(rb): failover
// Failover *DiscoveryFailover `json:",omitempty"` // sad path
clusterName := makeClusterName(upstreamID, target, cfgSnap.Datacenter)
c := &envoy.Cluster{
Name: clusterName,
AltStatName: clusterName, // TODO(rb): change this?
ConnectTimeout: groupResolver.ConnectTimeout,
ClusterDiscoveryType: &envoy.Cluster_Type{Type: envoy.Cluster_EDS},
CommonLbConfig: &envoy.Cluster_CommonLbConfig{
HealthyPanicThreshold: &envoytype.Percent{
Value: 0, // disable panic threshold
},
},
// TODO(rb): adjust load assignment
EdsClusterConfig: &envoy.Cluster_EdsClusterConfig{
EdsConfig: &envoycore.ConfigSource{
ConfigSourceSpecifier: &envoycore.ConfigSource_Ads{
Ads: &envoycore.AggregatedConfigSource{},
},
},
},
// Having an empty config enables outlier detection with default config.
OutlierDetection: &envoycluster.OutlierDetection{},
}
if chain.Protocol == "http2" || chain.Protocol == "grpc" {
c.Http2ProtocolOptions = &envoycore.Http2ProtocolOptions{}
}
// Enable TLS upstream with the configured client certificate.
c.TlsContext = &envoyauth.UpstreamTlsContext{
CommonTlsContext: makeCommonTLSContext(cfgSnap),
}
out = append(out, c)
}
return out, nil
}
// makeClusterName returns a string representation that uniquely identifies the
// cluster in a canonical but human readable way.
func makeClusterName(upstreamID string, target structs.DiscoveryTarget, currentDatacenter string) string {
var name string
if target.ServiceSubset != "" {
name = target.Service + "/" + target.ServiceSubset
} else {
name = target.Service
}
if target.Namespace != "" && target.Namespace != "default" {
name = target.Namespace + "/" + name
}
if target.Datacenter != "" && target.Datacenter != currentDatacenter {
name += "?dc=" + target.Datacenter
}
if upstreamID == target.Service {
// In the common case don't stutter.
return name
}
return upstreamID + "//" + name
}
// makeClusterFromUserConfig returns the listener config decoded from an
// arbitrary proto3 json format string or an error if it's invalid.
//
// For now we only support embedding in JSON strings because of the hcl parsing
// pain (see config.go comment above call to PatchSliceOfMaps). Until we
// refactor config parser a _lot_ user's opaque config that contains arrays will
// be mangled. We could actually fix that up in mapstructure which knows the
// type of the target so could resolve the slices to singletons unambiguously
// and it would work for us here... but we still have the problem that the
// config would render incorrectly in general in our HTTP API responses so we
// really need to fix it "properly".
//
// When we do that we can support just nesting the config directly into the
// JSON/hcl naturally but this is a stop-gap that gets us an escape hatch
// immediately. It's also probably not a bad thing to support long-term since
// any config generated by other systems will likely be in canonical protobuf
// from rather than our slight variant in JSON/hcl.
func makeClusterFromUserConfig(configJSON string) (*envoy.Cluster, error) {
var jsonFields map[string]*json.RawMessage
if err := json.Unmarshal([]byte(configJSON), &jsonFields); err != nil {
fmt.Println("Custom error", err, configJSON)
return nil, err
}
var c envoy.Cluster
if _, ok := jsonFields["@type"]; ok {
// Type field is present so decode it as a types.Any
var any types.Any
err := jsonpb.UnmarshalString(configJSON, &any)
if err != nil {
return nil, err
}
// And then unmarshal the listener again...
err = proto.Unmarshal(any.Value, &c)
if err != nil {
return nil, err
}
return &c, err
}
// No @type so try decoding as a straight listener.
err := jsonpb.UnmarshalString(configJSON, &c)
return &c, err
}
func (s *Server) makeMeshGatewayCluster(clusterName string, cfgSnap *proxycfg.ConfigSnapshot) (*envoy.Cluster, error) {
cfg, err := ParseMeshGatewayConfig(cfgSnap.Proxy.Config)
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.Printf("[WARN] envoy: failed to parse mesh gateway config: %s", err)
}
return &envoy.Cluster{
Name: clusterName,
ConnectTimeout: time.Duration(cfg.ConnectTimeoutMs) * time.Millisecond,
ClusterDiscoveryType: &envoy.Cluster_Type{Type: envoy.Cluster_EDS},
EdsClusterConfig: &envoy.Cluster_EdsClusterConfig{
EdsConfig: &envoycore.ConfigSource{
ConfigSourceSpecifier: &envoycore.ConfigSource_Ads{
Ads: &envoycore.AggregatedConfigSource{},
},
},
},
// Having an empty config enables outlier detection with default config.
OutlierDetection: &envoycluster.OutlierDetection{},
}, nil
}