feat(eventstore): accept transaction in push (#8945)

# Which Problems Are Solved

Push is not capable of external transactions.

# How the Problems Are Solved

A new function `PushWithClient` is added to the eventstore framework
which allows to pass a client which can either be a `*sql.Client` or
`*sql.Tx` and is used during push.

# Additional Changes

Added interfaces to database package.

# Additional Context

- part of https://github.com/zitadel/zitadel/issues/8931

---------

Co-authored-by: Livio Spring <livio.a@gmail.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

internal/eventstore/v3/eventstore.go

@@ -4,6 +4,7 @@ import (
 	"context"
 
 	"github.com/zitadel/zitadel/internal/database"
+	"github.com/zitadel/zitadel/internal/eventstore"
 )
 
 var (
@@ -11,12 +12,19 @@ var (
 	pushPlaceholderFmt string
 	// uniqueConstraintPlaceholderFmt defines the format of the unique constraint error returned from the database
 	uniqueConstraintPlaceholderFmt string
+
+	_ eventstore.Pusher = (*Eventstore)(nil)
 )
 
 type Eventstore struct {
 	client *database.DB
 }
 
+// Client implements the [eventstore.Pusher]
+func (es *Eventstore) Client() *database.DB {
+	return es.client
+}
+
 func NewEventstore(client *database.DB) *Eventstore {
 	switch client.Type() {
 	case "cockroach":

internal/eventstore/v3/field.go

@@ -11,6 +11,7 @@ import (
 	"strings"
 
 	"github.com/zitadel/zitadel/internal/api/authz"
+	"github.com/zitadel/zitadel/internal/database"
 	"github.com/zitadel/zitadel/internal/eventstore"
 	"github.com/zitadel/zitadel/internal/telemetry/tracing"
 	"github.com/zitadel/zitadel/internal/zerrors"
@@ -142,7 +143,7 @@ func buildSearchCondition(builder *strings.Builder, index int, conditions map[ev
 	return args
 }
 
-func handleFieldCommands(ctx context.Context, tx *sql.Tx, commands []eventstore.Command) error {
+func handleFieldCommands(ctx context.Context, tx database.Tx, commands []eventstore.Command) error {
 	for _, command := range commands {
 		if len(command.Fields()) > 0 {
 			if err := handleFieldOperations(ctx, tx, command.Fields()); err != nil {
@@ -153,7 +154,7 @@ func handleFieldCommands(ctx context.Context, tx *sql.Tx, commands []eventstore.
 	return nil
 }
 
-func handleFieldFillEvents(ctx context.Context, tx *sql.Tx, events []eventstore.FillFieldsEvent) error {
+func handleFieldFillEvents(ctx context.Context, tx database.Tx, events []eventstore.FillFieldsEvent) error {
 	for _, event := range events {
 		if len(event.Fields()) > 0 {
 			if err := handleFieldOperations(ctx, tx, event.Fields()); err != nil {
@@ -164,7 +165,7 @@ func handleFieldFillEvents(ctx context.Context, tx *sql.Tx, events []eventstore.
 	return nil
 }
 
-func handleFieldOperations(ctx context.Context, tx *sql.Tx, operations []*eventstore.FieldOperation) error {
+func handleFieldOperations(ctx context.Context, tx database.Tx, operations []*eventstore.FieldOperation) error {
 	for _, operation := range operations {
 		if operation.Set != nil {
 			if err := handleFieldSet(ctx, tx, operation.Set); err != nil {
@@ -182,7 +183,7 @@ func handleFieldOperations(ctx context.Context, tx *sql.Tx, operations []*events
 	return nil
 }
 
-func handleFieldSet(ctx context.Context, tx *sql.Tx, field *eventstore.Field) error {
+func handleFieldSet(ctx context.Context, tx database.Tx, field *eventstore.Field) error {
 	if len(field.UpsertConflictFields) == 0 {
 		return handleSearchInsert(ctx, tx, field)
 	}
@@ -193,7 +194,7 @@ const (
 	insertField = `INSERT INTO eventstore.fields (instance_id, resource_owner, aggregate_type, aggregate_id, object_type, object_id, object_revision, field_name, value, value_must_be_unique, should_index) VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11)`
 )
 
-func handleSearchInsert(ctx context.Context, tx *sql.Tx, field *eventstore.Field) error {
+func handleSearchInsert(ctx context.Context, tx database.Tx, field *eventstore.Field) error {
 	value, err := json.Marshal(field.Value.Value)
 	if err != nil {
 		return zerrors.ThrowInvalidArgument(err, "V3-fcrW1", "unable to marshal field value")
@@ -222,7 +223,7 @@ const (
 	fieldsUpsertSuffix = ` RETURNING * ) INSERT INTO eventstore.fields (instance_id, resource_owner, aggregate_type, aggregate_id, object_type, object_id, object_revision, field_name, value, value_must_be_unique, should_index) SELECT $1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11 WHERE NOT EXISTS (SELECT 1 FROM upsert)`
 )
 
-func handleSearchUpsert(ctx context.Context, tx *sql.Tx, field *eventstore.Field) error {
+func handleSearchUpsert(ctx context.Context, tx database.Tx, field *eventstore.Field) error {
 	value, err := json.Marshal(field.Value.Value)
 	if err != nil {
 		return zerrors.ThrowInvalidArgument(err, "V3-fcrW1", "unable to marshal field value")
@@ -268,7 +269,7 @@ func writeUpsertField(fields []eventstore.FieldType) string {
 
 const removeSearch = `DELETE FROM eventstore.fields WHERE `
 
-func handleSearchDelete(ctx context.Context, tx *sql.Tx, clauses map[eventstore.FieldType]any) error {
+func handleSearchDelete(ctx context.Context, tx database.Tx, clauses map[eventstore.FieldType]any) error {
 	if len(clauses) == 0 {
 		return zerrors.ThrowInvalidArgument(nil, "V3-oqlBZ", "no conditions")
 	}

internal/eventstore/v3/push.go

@@ -14,6 +14,7 @@ import (
 	"github.com/zitadel/logging"
 
 	"github.com/zitadel/zitadel/internal/api/authz"
+	"github.com/zitadel/zitadel/internal/database"
 	"github.com/zitadel/zitadel/internal/database/dialect"
 	"github.com/zitadel/zitadel/internal/eventstore"
 	"github.com/zitadel/zitadel/internal/telemetry/tracing"
@@ -22,13 +23,45 @@ import (
 
 var appNamePrefix = dialect.DBPurposeEventPusher.AppName() + "_"
 
-func (es *Eventstore) Push(ctx context.Context, commands ...eventstore.Command) (events []eventstore.Event, err error) {
+var pushTxOpts = &sql.TxOptions{
+	Isolation: sql.LevelReadCommitted,
+	ReadOnly:  false,
+}
+
+func (es *Eventstore) Push(ctx context.Context, client database.QueryExecuter, commands ...eventstore.Command) (events []eventstore.Event, err error) {
 	ctx, span := tracing.NewSpan(ctx)
 	defer func() { span.EndWithError(err) }()
 
-	tx, err := es.client.BeginTx(ctx, nil)
-	if err != nil {
-		return nil, err
+	var tx database.Tx
+	switch c := client.(type) {
+	case database.Tx:
+		tx = c
+	case database.Client:
+		// We cannot use READ COMMITTED on CockroachDB because we use cluster_logical_timestamp() which is not supported in this isolation level
+		var opts *sql.TxOptions
+		if es.client.Database.Type() == "postgres" {
+			opts = pushTxOpts
+		}
+		tx, err = c.BeginTx(ctx, opts)
+		if err != nil {
+			return nil, err
+		}
+		defer func() {
+			err = database.CloseTransaction(tx, err)
+		}()
+	default:
+		// We cannot use READ COMMITTED on CockroachDB because we use cluster_logical_timestamp() which is not supported in this isolation level
+		var opts *sql.TxOptions
+		if es.client.Database.Type() == "postgres" {
+			opts = pushTxOpts
+		}
+		tx, err = es.client.BeginTx(ctx, opts)
+		if err != nil {
+			return nil, err
+		}
+		defer func() {
+			err = database.CloseTransaction(tx, err)
+		}()
 	}
 	// tx is not closed because [crdb.ExecuteInTx] takes care of that
 	var (
@@ -42,43 +75,30 @@ func (es *Eventstore) Push(ctx context.Context, commands ...eventstore.Command)
 		return nil, err
 	}
 
-	// needs to be set like this because psql complains about parameters in the SET statement
-	_, err = tx.ExecContext(ctx, "SET application_name = '"+appNamePrefix+authz.GetInstance(ctx).InstanceID()+"'")
+	sequences, err = latestSequences(ctx, tx, commands)
 	if err != nil {
-		logging.WithError(err).Warn("failed to set application name")
 		return nil, err
 	}
 
-	err = crdb.ExecuteInTx(ctx, &transaction{tx}, func() (err error) {
-		inTxCtx, span := tracing.NewSpan(ctx)
-		defer func() { span.EndWithError(err) }()
+	events, err = insertEvents(ctx, tx, sequences, commands)
+	if err != nil {
+		return nil, err
+	}
 
-		sequences, err = latestSequences(inTxCtx, tx, commands)
+	if err = handleUniqueConstraints(ctx, tx, commands); err != nil {
+		return nil, err
+	}
+
+	// CockroachDB by default does not allow multiple modifications of the same table using ON CONFLICT
+	// Thats why we enable it manually
+	if es.client.Type() == "cockroach" {
+		_, err = tx.Exec("SET enable_multiple_modifications_of_table = on")
 		if err != nil {
-			return err
+			return nil, err
 		}
+	}
 
-		events, err = insertEvents(inTxCtx, tx, sequences, commands)
-		if err != nil {
-			return err
-		}
-
-		if err = handleUniqueConstraints(inTxCtx, tx, commands); err != nil {
-			return err
-		}
-
-		// CockroachDB by default does not allow multiple modifications of the same table using ON CONFLICT
-		// Thats why we enable it manually
-		if es.client.Type() == "cockroach" {
-			_, err = tx.Exec("SET enable_multiple_modifications_of_table = on")
-			if err != nil {
-				return err
-			}
-		}
-
-		return handleFieldCommands(inTxCtx, tx, commands)
-	})
-
+	err = handleFieldCommands(ctx, tx, commands)
 	if err != nil {
 		return nil, err
 	}
@@ -89,7 +109,7 @@ func (es *Eventstore) Push(ctx context.Context, commands ...eventstore.Command)
 //go:embed push.sql
 var pushStmt string
 
-func insertEvents(ctx context.Context, tx *sql.Tx, sequences []*latestSequence, commands []eventstore.Command) ([]eventstore.Event, error) {
+func insertEvents(ctx context.Context, tx database.Tx, sequences []*latestSequence, commands []eventstore.Command) ([]eventstore.Event, error) {
 	events, placeholders, args, err := mapCommands(commands, sequences)
 	if err != nil {
 		return nil, err
@@ -186,7 +206,7 @@ func mapCommands(commands []eventstore.Command, sequences []*latestSequence) (ev
 }
 
 type transaction struct {
-	*sql.Tx
+	database.Tx
 }
 
 var _ crdb.Tx = (*transaction)(nil)

internal/eventstore/v3/sequence.go

@@ -10,6 +10,7 @@ import (
 	"github.com/zitadel/logging"
 
 	"github.com/zitadel/zitadel/internal/api/authz"
+	"github.com/zitadel/zitadel/internal/database"
 	"github.com/zitadel/zitadel/internal/eventstore"
 	"github.com/zitadel/zitadel/internal/zerrors"
 )
@@ -22,7 +23,7 @@ type latestSequence struct {
 //go:embed sequences_query.sql
 var latestSequencesStmt string
 
-func latestSequences(ctx context.Context, tx *sql.Tx, commands []eventstore.Command) ([]*latestSequence, error) {
+func latestSequences(ctx context.Context, tx database.Tx, commands []eventstore.Command) ([]*latestSequence, error) {
 	sequences := commandsToSequences(ctx, commands)
 
 	conditions, args := sequencesToSql(sequences)

internal/eventstore/v3/unique_constraints.go

@@ -2,7 +2,6 @@ package eventstore
 
 import (
 	"context"
-	"database/sql"
 	_ "embed"
 	"errors"
 	"fmt"
@@ -11,6 +10,7 @@ import (
 	"github.com/jackc/pgx/v5/pgconn"
 	"github.com/zitadel/logging"
 
+	"github.com/zitadel/zitadel/internal/database"
 	"github.com/zitadel/zitadel/internal/eventstore"
 	"github.com/zitadel/zitadel/internal/zerrors"
 )
@@ -24,7 +24,7 @@ var (
 	addConstraintStmt string
 )
 
-func handleUniqueConstraints(ctx context.Context, tx *sql.Tx, commands []eventstore.Command) error {
+func handleUniqueConstraints(ctx context.Context, tx database.Tx, commands []eventstore.Command) error {
 	deletePlaceholders := make([]string, 0)
 	deleteArgs := make([]any, 0)