open-consul/agent/xds/clusters.go

485 lines
16 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/connect"
"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, 0, len(cfgSnap.Proxy.Upstreams)+1)
// Include the "app" cluster for the public listener
appCluster, err := s.makeAppCluster(cfgSnap, LocalAppClusterName, "", cfgSnap.Proxy.LocalServicePort)
if err != nil {
return nil, err
}
clusters = append(clusters, appCluster)
for _, u := range cfgSnap.Proxy.Upstreams {
id := u.Identifier()
if u.DestinationType == structs.UpstreamDestTypePreparedQuery {
upstreamCluster, err := s.makeUpstreamClusterForPreparedQuery(u, cfgSnap)
if err != nil {
return nil, err
}
clusters = append(clusters, upstreamCluster)
} else {
chain := cfgSnap.ConnectProxy.DiscoveryChain[id]
upstreamClusters, err := s.makeUpstreamClustersForDiscoveryChain(u, chain, cfgSnap)
if err != nil {
return nil, err
}
for _, cluster := range upstreamClusters {
clusters = append(clusters, cluster)
}
}
}
cfgSnap.Proxy.Expose.Finalize(s.Logger)
paths := cfgSnap.Proxy.Expose.Paths
// Add service health checks to the list of paths to create clusters for if needed
if cfgSnap.Proxy.Expose.Checks {
// TODO (namespaces) update with real entmeta
var psid structs.ServiceID
psid.Init(cfgSnap.Proxy.DestinationServiceID, structs.DefaultEnterpriseMeta())
for _, check := range s.CheckFetcher.ServiceHTTPBasedChecks(psid) {
p, err := parseCheckPath(check)
if err != nil {
s.Logger.Printf("[WARN] envoy: failed to create cluster for check '%s': %v", check.CheckID, err)
continue
}
paths = append(paths, p)
}
}
// Create a new cluster if we need to expose a port that is different from the service port
for _, path := range paths {
if path.LocalPathPort == cfgSnap.Proxy.LocalServicePort {
continue
}
c, err := s.makeAppCluster(cfgSnap, makeExposeClusterName(path.LocalPathPort), path.Protocol, path.LocalPathPort)
if err != nil {
s.Logger.Printf("[WARN] envoy: failed to make local cluster for '%s': %s", path.Path, err)
continue
}
clusters = append(clusters, c)
}
return clusters, nil
}
func makeExposeClusterName(destinationPort int) string {
return fmt.Sprintf("exposed_cluster_%d", destinationPort)
}
// 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 := connect.DatacenterSNI(dc, cfgSnap.Roots.TrustDomain)
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 := connect.ServiceSNI(svc, "", "default", cfgSnap.Datacenter, cfgSnap.Roots.TrustDomain)
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 := connect.ServiceSNI(svc, subsetName, "default", cfgSnap.Datacenter, cfgSnap.Roots.TrustDomain)
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, name, pathProtocol string, port int) (*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)
}
addr := cfgSnap.Proxy.LocalServiceAddress
if addr == "" {
addr = "127.0.0.1"
}
c = &envoy.Cluster{
Name: name,
ConnectTimeout: time.Duration(cfg.LocalConnectTimeoutMs) * time.Millisecond,
ClusterDiscoveryType: &envoy.Cluster_Type{Type: envoy.Cluster_STATIC},
LoadAssignment: &envoy.ClusterLoadAssignment{
ClusterName: name,
Endpoints: []envoyendpoint.LocalityLbEndpoints{
{
LbEndpoints: []envoyendpoint.LbEndpoint{
makeEndpoint(name,
addr,
port),
},
},
},
},
}
if cfg.Protocol == "http2" || cfg.Protocol == "grpc" || pathProtocol == "http2" {
c.Http2ProtocolOptions = &envoycore.Http2ProtocolOptions{}
}
return c, err
}
func (s *Server) makeUpstreamClusterForPreparedQuery(upstream structs.Upstream, cfgSnap *proxycfg.ConfigSnapshot) (*envoy.Cluster, error) {
var c *envoy.Cluster
var err error
dc := upstream.Datacenter
if dc == "" {
dc = cfgSnap.Datacenter
}
sni := connect.UpstreamSNI(&upstream, "", dc, cfgSnap.Roots.TrustDomain)
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: sni,
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{},
},
},
},
CircuitBreakers: &envoycluster.CircuitBreakers{
Thresholds: makeThresholdsIfNeeded(cfg.Limits),
},
// 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(
upstream structs.Upstream,
chain *structs.CompiledDiscoveryChain,
cfgSnap *proxycfg.ConfigSnapshot,
) ([]*envoy.Cluster, error) {
if chain == nil {
return nil, fmt.Errorf("cannot create upstream cluster without discovery chain")
}
cfg, err := ParseUpstreamConfigNoDefaults(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)
}
var escapeHatchCluster *envoy.Cluster
if cfg.ClusterJSON != "" {
if chain.IsDefault() {
// 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.ClusterJSON)
if err != nil {
return nil, err
}
} else {
s.Logger.Printf("[WARN] envoy: ignoring escape hatch setting Upstream[%s].Config[%s] because a discovery chain for %q is configured",
upstream.Identifier(), "envoy_cluster_json", chain.ServiceName)
}
}
id := upstream.Identifier()
chainEndpointMap, ok := cfgSnap.ConnectProxy.WatchedUpstreamEndpoints[id]
if !ok {
// this should not happen
return nil, fmt.Errorf("no endpoint map for upstream %q", id)
}
var out []*envoy.Cluster
for _, node := range chain.Nodes {
if node.Type != structs.DiscoveryGraphNodeTypeResolver {
continue
}
failover := node.Resolver.Failover
targetID := node.Resolver.Target
target := chain.Targets[targetID]
// Determine if we have to generate the entire cluster differently.
failoverThroughMeshGateway := chain.WillFailoverThroughMeshGateway(node)
sni := target.SNI
clusterName := CustomizeClusterName(target.Name, chain)
if failoverThroughMeshGateway {
actualTargetID := firstHealthyTarget(
chain.Targets,
chainEndpointMap,
targetID,
failover.Targets,
)
if actualTargetID != targetID {
actualTarget := chain.Targets[actualTargetID]
sni = actualTarget.SNI
}
}
s.Logger.Printf("[DEBUG] xds.clusters - generating cluster for %s", clusterName)
c := &envoy.Cluster{
Name: clusterName,
AltStatName: clusterName,
ConnectTimeout: node.Resolver.ConnectTimeout,
ClusterDiscoveryType: &envoy.Cluster_Type{Type: envoy.Cluster_EDS},
CommonLbConfig: &envoy.Cluster_CommonLbConfig{
HealthyPanicThreshold: &envoytype.Percent{
Value: 0, // disable panic threshold
},
},
EdsClusterConfig: &envoy.Cluster_EdsClusterConfig{
EdsConfig: &envoycore.ConfigSource{
ConfigSourceSpecifier: &envoycore.ConfigSource_Ads{
Ads: &envoycore.AggregatedConfigSource{},
},
},
},
CircuitBreakers: &envoycluster.CircuitBreakers{
Thresholds: makeThresholdsIfNeeded(cfg.Limits),
},
// Having an empty config enables outlier detection with default config.
OutlierDetection: &envoycluster.OutlierDetection{},
}
proto := cfg.Protocol
if proto == "" {
proto = chain.Protocol
}
if proto == "" {
proto = "tcp"
}
if proto == "http2" || proto == "grpc" {
c.Http2ProtocolOptions = &envoycore.Http2ProtocolOptions{}
}
// Enable TLS upstream with the configured client certificate.
c.TlsContext = &envoyauth.UpstreamTlsContext{
CommonTlsContext: makeCommonTLSContext(cfgSnap),
Sni: sni,
}
out = append(out, c)
}
if escapeHatchCluster != nil {
if len(out) != 1 {
return nil, fmt.Errorf("cannot inject escape hatch cluster when discovery chain had no nodes")
}
defaultCluster := out[0]
// Overlay what the user provided.
escapeHatchCluster.TlsContext = defaultCluster.TlsContext
out = []*envoy.Cluster{escapeHatchCluster}
}
return out, nil
}
// 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
}
func makeThresholdsIfNeeded(limits UpstreamLimits) []*envoycluster.CircuitBreakers_Thresholds {
var empty UpstreamLimits
// Make sure to not create any thresholds when passed the zero-value in order
// to rely on Envoy defaults
if limits == empty {
return nil
}
threshold := &envoycluster.CircuitBreakers_Thresholds{}
// Likewise, make sure to not set any threshold values on the zero-value in
// order to rely on Envoy defaults
if limits.MaxConnections != nil {
threshold.MaxConnections = makeUint32Value(*limits.MaxConnections)
}
if limits.MaxPendingRequests != nil {
threshold.MaxPendingRequests = makeUint32Value(*limits.MaxPendingRequests)
}
if limits.MaxConcurrentRequests != nil {
threshold.MaxRequests = makeUint32Value(*limits.MaxConcurrentRequests)
}
return []*envoycluster.CircuitBreakers_Thresholds{threshold}
}