controlplane: save configuration events to databroker (#2153)

* envoy: save events to databroker

* controlplane: add tests for envoy configuration events

* format imports

internal/controlplane/events.go

@@ -0,0 +1,112 @@
+package controlplane
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/google/uuid"
+	"google.golang.org/protobuf/proto"
+	"google.golang.org/protobuf/types/known/anypb"
+
+	"github.com/pomerium/pomerium/internal/log"
+	"github.com/pomerium/pomerium/pkg/grpc"
+	configpb "github.com/pomerium/pomerium/pkg/grpc/config"
+	databrokerpb "github.com/pomerium/pomerium/pkg/grpc/databroker"
+)
+
+const maxEnvoyConfigurationEvents = 50
+
+func (srv *Server) handleEnvoyConfigurationEvent(evt *configpb.EnvoyConfigurationEvent) {
+	select {
+	case srv.envoyConfigurationEvents <- evt:
+	default:
+		log.Warn(context.Background()).
+			Interface("event", evt).
+			Msg("controlplane: dropping envoy configuration event due to full channel")
+	}
+}
+
+func (srv *Server) runEnvoyConfigurationEventHandler(ctx context.Context) error {
+	for {
+		var evt *configpb.EnvoyConfigurationEvent
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+		case evt = <-srv.envoyConfigurationEvents:
+		}
+		err := srv.storeEnvoyConfigurationEvent(ctx, evt)
+		if err != nil {
+			log.Error(ctx).Err(err).Msg("controlplane: error storing configuration event")
+		}
+	}
+}
+
+func (srv *Server) storeEnvoyConfigurationEvent(ctx context.Context, evt *configpb.EnvoyConfigurationEvent) error {
+	any, err := anypb.New(evt)
+	if err != nil {
+		return err
+	}
+
+	client, err := srv.getDataBrokerClient(ctx)
+	if err != nil {
+		return err
+	}
+
+	if !srv.haveSetEnvoyConfigurationEventOptions {
+		_, err = client.SetOptions(ctx, &databrokerpb.SetOptionsRequest{
+			Type: any.GetTypeUrl(),
+			Options: &databrokerpb.Options{
+				Capacity: proto.Uint64(maxEnvoyConfigurationEvents),
+			},
+		})
+		if err != nil {
+			return err
+		}
+		srv.haveSetEnvoyConfigurationEventOptions = true
+	}
+
+	_, err = client.Put(ctx, &databrokerpb.PutRequest{
+		Record: &databrokerpb.Record{
+			Type: any.GetTypeUrl(),
+			Id:   uuid.NewString(),
+			Data: any,
+		},
+	})
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (srv *Server) getDataBrokerClient(ctx context.Context) (databrokerpb.DataBrokerServiceClient, error) {
+	options := srv.currentConfig.Load().Options
+
+	sharedKey, err := options.GetSharedKey()
+	if err != nil {
+		return nil, err
+	}
+
+	urls, err := options.GetDataBrokerURLs()
+	if err != nil {
+		return nil, err
+	}
+
+	cc, err := grpc.GetGRPCClientConn(ctx, "databroker", &grpc.Options{
+		Addrs:                   urls,
+		OverrideCertificateName: options.OverrideCertificateName,
+		CA:                      options.CA,
+		CAFile:                  options.CAFile,
+		RequestTimeout:          options.GRPCClientTimeout,
+		ClientDNSRoundRobin:     options.GRPCClientDNSRoundRobin,
+		WithInsecure:            options.GetGRPCInsecure(),
+		InstallationID:          options.InstallationID,
+		ServiceName:             options.Services,
+		SignedJWTKey:            sharedKey,
+	})
+	if err != nil {
+		return nil, fmt.Errorf("controlplane: error creating databroker connection: %w", err)
+	}
+	client := databrokerpb.NewDataBrokerServiceClient(cc)
+	return client, nil
+}