zitadel/internal/eventstore/handler/crdb/lock.go
Tim Möhlmann f680dd934d
refactor: rename package errors to zerrors (#7039)
* chore: rename package errors to zerrors

* rename package errors to gerrors

* fix error related linting issues

* fix zitadel error assertion

* fix gosimple linting issues

* fix deprecated linting issues

* resolve gci linting issues

* fix import structure

---------

Co-authored-by: Elio Bischof <elio@zitadel.com>
2023-12-08 15:30:55 +01:00

108 lines
3.4 KiB
Go

package crdb
import (
"context"
"database/sql"
"fmt"
"strconv"
"strings"
"time"
"github.com/zitadel/logging"
"github.com/zitadel/zitadel/internal/database"
"github.com/zitadel/zitadel/internal/id"
"github.com/zitadel/zitadel/internal/zerrors"
)
const (
lockStmtFormat = "INSERT INTO %[1]s" +
" (locker_id, locked_until, projection_name, instance_id) VALUES %[2]s" +
" ON CONFLICT (projection_name, instance_id)" +
" DO UPDATE SET locker_id = $1, locked_until = now()+$2::INTERVAL" +
" WHERE %[1]s.projection_name = $3 AND %[1]s.instance_id = ANY ($%[3]d) AND (%[1]s.locker_id = $1 OR %[1]s.locked_until < now())"
)
type Locker interface {
Lock(ctx context.Context, lockDuration time.Duration, instanceIDs ...string) <-chan error
Unlock(instanceIDs ...string) error
}
type locker struct {
client *sql.DB
lockStmt func(values string, instances int) string
workerName string
projectionName string
}
func NewLocker(client *sql.DB, lockTable, projectionName string) Locker {
workerName, err := id.SonyFlakeGenerator().Next()
logging.OnError(err).Panic("unable to generate lockID")
return &locker{
client: client,
lockStmt: func(values string, instances int) string {
return fmt.Sprintf(lockStmtFormat, lockTable, values, instances)
},
workerName: workerName,
projectionName: projectionName,
}
}
func (h *locker) Lock(ctx context.Context, lockDuration time.Duration, instanceIDs ...string) <-chan error {
errs := make(chan error)
go h.handleLock(ctx, errs, lockDuration, instanceIDs...)
return errs
}
func (h *locker) handleLock(ctx context.Context, errs chan error, lockDuration time.Duration, instanceIDs ...string) {
renewLock := time.NewTimer(0)
for {
select {
case <-renewLock.C:
errs <- h.renewLock(ctx, lockDuration, instanceIDs...)
//refresh the lock 500ms before it times out. 500ms should be enough for one transaction
renewLock.Reset(lockDuration - (500 * time.Millisecond))
case <-ctx.Done():
close(errs)
renewLock.Stop()
return
}
}
}
func (h *locker) renewLock(ctx context.Context, lockDuration time.Duration, instanceIDs ...string) error {
lockStmt, values := h.lockStatement(lockDuration, instanceIDs)
res, err := h.client.ExecContext(ctx, lockStmt, values...)
if err != nil {
return zerrors.ThrowInternal(err, "CRDB-uaDoR", "unable to execute lock")
}
if rows, _ := res.RowsAffected(); rows == 0 {
return zerrors.ThrowAlreadyExists(nil, "CRDB-mmi4J", "projection already locked")
}
return nil
}
func (h *locker) Unlock(instanceIDs ...string) error {
lockStmt, values := h.lockStatement(0, instanceIDs)
_, err := h.client.Exec(lockStmt, values...)
if err != nil {
return zerrors.ThrowUnknown(err, "CRDB-JjfwO", "unlock failed")
}
return nil
}
func (h *locker) lockStatement(lockDuration time.Duration, instanceIDs database.TextArray[string]) (string, []interface{}) {
valueQueries := make([]string, len(instanceIDs))
values := make([]interface{}, len(instanceIDs)+4)
values[0] = h.workerName
//the unit of crdb interval is seconds (https://www.cockroachlabs.com/docs/stable/interval.html).
values[1] = lockDuration
values[2] = h.projectionName
for i, instanceID := range instanceIDs {
valueQueries[i] = "($1, now()+$2::INTERVAL, $3, $" + strconv.Itoa(i+4) + ")"
values[i+3] = instanceID
}
values[len(values)-1] = instanceIDs
return h.lockStmt(strings.Join(valueQueries, ", "), len(values)), values
}