feat(eventstore): increase parallel write capabilities (#5940)

This implementation increases parallel write capabilities of the eventstore.
Please have a look at the technical advisories: [05](https://zitadel.com/docs/support/advisory/a10005) and  [06](https://zitadel.com/docs/support/advisory/a10006).
The implementation of eventstore.push is rewritten and stored events are migrated to a new table `eventstore.events2`.
If you are using cockroach: make sure that the database user of ZITADEL has `VIEWACTIVITY` grant. This is used to query events.

internal/notification/handlers/telemetry_pusher.go

@@ -3,7 +3,6 @@ package handlers
 import (
 	"context"
 	"fmt"
-	"math"
 	"net/http"
 	"time"
 
@@ -14,13 +13,11 @@ import (
 	"github.com/zitadel/zitadel/internal/command"
 	"github.com/zitadel/zitadel/internal/errors"
 	"github.com/zitadel/zitadel/internal/eventstore"
-	"github.com/zitadel/zitadel/internal/eventstore/handler"
-	"github.com/zitadel/zitadel/internal/eventstore/handler/crdb"
+	"github.com/zitadel/zitadel/internal/eventstore/handler/v2"
 	"github.com/zitadel/zitadel/internal/notification/channels/webhook"
 	_ "github.com/zitadel/zitadel/internal/notification/statik"
 	"github.com/zitadel/zitadel/internal/notification/types"
 	"github.com/zitadel/zitadel/internal/query"
-	"github.com/zitadel/zitadel/internal/query/projection"
 	"github.com/zitadel/zitadel/internal/repository/milestone"
 	"github.com/zitadel/zitadel/internal/repository/pseudo"
 )
@@ -37,7 +34,6 @@ type TelemetryPusherConfig struct {
 }
 
 type telemetryPusher struct {
-	crdb.StatementHandler
 	cfg      TelemetryPusherConfig
 	commands *command.Commands
 	queries  *NotificationQueries
@@ -47,28 +43,33 @@ type telemetryPusher struct {
 func NewTelemetryPusher(
 	ctx context.Context,
 	telemetryCfg TelemetryPusherConfig,
-	handlerCfg crdb.StatementHandlerConfig,
+	handlerCfg handler.Config,
 	commands *command.Commands,
 	queries *NotificationQueries,
 	channels types.ChannelChains,
-) *telemetryPusher {
-	p := new(telemetryPusher)
-	handlerCfg.ProjectionName = TelemetryProjectionTable
-	handlerCfg.Reducers = p.reducers()
-	p.cfg = telemetryCfg
-	handlerCfg.ConcurrentInstances = math.MaxInt
-	p.StatementHandler = crdb.NewStatementHandler(ctx, handlerCfg)
-	p.commands = commands
-	p.queries = queries
-	p.channels = channels
-	projection.TelemetryPusherProjection = p
-	return p
+) *handler.Handler {
+	pusher := &telemetryPusher{
+		cfg:      telemetryCfg,
+		commands: commands,
+		queries:  queries,
+		channels: channels,
+	}
+	handlerCfg.TriggerWithoutEvents = pusher.pushMilestones
+	return handler.NewHandler(
+		ctx,
+		&handlerCfg,
+		pusher,
+	)
 }
 
-func (t *telemetryPusher) reducers() []handler.AggregateReducer {
+func (u *telemetryPusher) Name() string {
+	return TelemetryProjectionTable
+}
+
+func (t *telemetryPusher) Reducers() []handler.AggregateReducer {
 	return []handler.AggregateReducer{{
 		Aggregate: pseudo.AggregateType,
-		EventRedusers: []handler.EventReducer{{
+		EventReducers: []handler.EventReducer{{
 			Event:  pseudo.ScheduledEventType,
 			Reduce: t.pushMilestones,
 		}},
@@ -82,41 +83,42 @@ func (t *telemetryPusher) pushMilestones(event eventstore.Event) (*handler.State
 		return nil, errors.ThrowInvalidArgumentf(nil, "HANDL-lDTs5", "reduce.wrong.event.type %s", event.Type())
 	}
 
-	isReached, err := query.NewNotNullQuery(query.MilestoneReachedDateColID)
-	if err != nil {
-		return nil, err
-	}
-	isNotPushed, err := query.NewIsNullQuery(query.MilestonePushedDateColID)
-	if err != nil {
-		return nil, err
-	}
-	hasPrimaryDomain, err := query.NewNotNullQuery(query.MilestonePrimaryDomainColID)
-	if err != nil {
-		return nil, err
-	}
-	unpushedMilestones, err := t.queries.Queries.SearchMilestones(ctx, scheduledEvent.InstanceIDs, &query.MilestonesSearchQueries{
-		SearchRequest: query.SearchRequest{
-			Limit:         t.cfg.Limit,
-			SortingColumn: query.MilestoneReachedDateColID,
-			Asc:           true,
-		},
-		Queries: []query.SearchQuery{isReached, isNotPushed, hasPrimaryDomain},
-	})
-	if err != nil {
-		return nil, err
-	}
-	var errs int
-	for _, ms := range unpushedMilestones.Milestones {
-		if err = t.pushMilestone(ctx, scheduledEvent, ms); err != nil {
-			errs++
-			logging.Warnf("pushing milestone %+v failed: %s", *ms, err.Error())
+	return handler.NewStatement(event, func(ex handler.Executer, projectionName string) error {
+		isReached, err := query.NewNotNullQuery(query.MilestoneReachedDateColID)
+		if err != nil {
+			return err
 		}
-	}
-	if errs > 0 {
-		return nil, fmt.Errorf("pushing %d of %d milestones failed", errs, unpushedMilestones.Count)
-	}
-
-	return crdb.NewNoOpStatement(scheduledEvent), nil
+		isNotPushed, err := query.NewIsNullQuery(query.MilestonePushedDateColID)
+		if err != nil {
+			return err
+		}
+		hasPrimaryDomain, err := query.NewNotNullQuery(query.MilestonePrimaryDomainColID)
+		if err != nil {
+			return err
+		}
+		unpushedMilestones, err := t.queries.Queries.SearchMilestones(ctx, scheduledEvent.InstanceIDs, &query.MilestonesSearchQueries{
+			SearchRequest: query.SearchRequest{
+				Limit:         t.cfg.Limit,
+				SortingColumn: query.MilestoneReachedDateColID,
+				Asc:           true,
+			},
+			Queries: []query.SearchQuery{isReached, isNotPushed, hasPrimaryDomain},
+		})
+		if err != nil {
+			return err
+		}
+		var errs int
+		for _, ms := range unpushedMilestones.Milestones {
+			if err = t.pushMilestone(ctx, scheduledEvent, ms); err != nil {
+				errs++
+				logging.Warnf("pushing milestone %+v failed: %s", *ms, err.Error())
+			}
+		}
+		if errs > 0 {
+			return fmt.Errorf("pushing %d of %d milestones failed", errs, unpushedMilestones.Count)
+		}
+		return nil
+	}), nil
 }
 
 func (t *telemetryPusher) pushMilestone(ctx context.Context, event *pseudo.ScheduledEvent, ms *query.Milestone) error {