Files
tasks/common/persistence/sql/test_sql_persistence.go
Tim Deeb-SwihartandGitHub be7b5514a5 Reconnect to SQL databases when connections fail (#5926)
## What changed?

Both our PostgreSQL and MySQL database backends will now automatically
reconnect to the database when certain errors occur: all errors chosen
have been experienced when testing this behavior through an AWS Aurora
RDS failover of either MySQL or PostgreSQL.

For both backends we will reconnect when we see:
- `ECONNRESET`
- `ECONNABORTED`
- `ECONNREFUSED`
- `io.EOF`
- `io.ErrUnexpectedEOF`
- `database/sql/driver.ErrBadConn`

for postgres we will also reconnect on the following SQLStates:
- `25006` read-only transaction
- `57P03` cannot connect now
- `0A000` feature not supported, but ONLY when the message is `cannot
set transaction read-write mode during recovery`

for mysql we will also reconnect when we see the following error codes:
- `1040` too many connections 
- `1792` read-only transaction (SQLstate `25006`)
- `1836` running in read-only mode

This logic is easily extensible should we discover more failure modes
over time

## Why?

We've had multiple community reports of Temporal problems during RDS
failover. One part of this is the fact that we wouldn't necessarily
reconnect; we were at the whims of our chosen SQL abstraction's
connection pooling logic.

## How did you test it?

I manually tested this functionality in the presence of repeated RDS
failovers: 

- [x] postgres12 plugin with pq driver
- [x] postgres12 plugin with pgx driver
- [x] mysql plugin

Automated testing will be added to our regular testing pipelines once
our infrastructure friends have added the support I need (it's in
progress)

## Potential risks

We're concerned there's a correctness issue in our PostgreSQL backend
that's related to our behavior during an RDS failover. If we merge this
before I figure out what's going on, we could hide the issue and make it
harder to reproduce.

## Documentation
N/A

## Is hotfix candidate?
Yes?
2024-05-17 16:59:15 -07:00

230 lines
6.5 KiB
Go

// The MIT License
//
// Copyright (c) 2020 Temporal Technologies Inc. All rights reserved.
//
// Copyright (c) 2020 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
package sql
import (
"fmt"
"os"
"path"
"strings"
"time"
"go.temporal.io/server/common/backoff"
"go.temporal.io/server/common/config"
"go.temporal.io/server/common/dynamicconfig"
"go.temporal.io/server/common/log"
"go.temporal.io/server/common/log/tag"
"go.temporal.io/server/common/metrics"
p "go.temporal.io/server/common/persistence"
"go.temporal.io/server/common/persistence/sql/sqlplugin"
"go.temporal.io/server/common/primitives"
"go.temporal.io/server/common/resolver"
"go.temporal.io/server/tests/testutils"
)
// TestCluster allows executing cassandra operations in testing.
type TestCluster struct {
dbName string
schemaDir string
cfg config.SQL
faultInjection *config.FaultInjection
logger log.Logger
}
// NewTestCluster returns a new SQL test cluster
func NewTestCluster(
pluginName string,
dbName string,
username string,
password string,
host string,
port int,
connectAttributes map[string]string,
schemaDir string,
faultInjection *config.FaultInjection,
logger log.Logger,
) *TestCluster {
var result TestCluster
result.logger = logger
result.dbName = dbName
result.schemaDir = schemaDir
result.cfg = config.SQL{
User: username,
Password: password,
ConnectAddr: fmt.Sprintf("%v:%v", host, port),
ConnectProtocol: "tcp",
PluginName: pluginName,
DatabaseName: dbName,
TaskScanPartitions: 4,
ConnectAttributes: connectAttributes,
}
result.faultInjection = faultInjection
return &result
}
// DatabaseName from PersistenceTestCluster interface
func (s *TestCluster) DatabaseName() string {
return s.dbName
}
// SetupTestDatabase from PersistenceTestCluster interface
func (s *TestCluster) SetupTestDatabase() {
s.CreateDatabase()
if s.schemaDir == "" {
s.logger.Info("No schema directory provided, skipping schema setup")
return
}
schemaDir := s.schemaDir + "/"
if !strings.HasPrefix(schemaDir, "/") && !strings.HasPrefix(schemaDir, "../") {
temporalPackageDir := testutils.GetRepoRootDirectory()
schemaDir = path.Join(temporalPackageDir, schemaDir)
}
s.LoadSchema(path.Join(schemaDir, "temporal", "schema.sql"))
s.LoadSchema(path.Join(schemaDir, "visibility", "schema.sql"))
}
// Config returns the persistence config for connecting to this test cluster
func (s *TestCluster) Config() config.Persistence {
cfg := s.cfg
return config.Persistence{
DefaultStore: "test",
VisibilityStore: "test",
DataStores: map[string]config.DataStore{
"test": {SQL: &cfg, FaultInjection: s.faultInjection},
},
TransactionSizeLimit: dynamicconfig.GetIntPropertyFn(primitives.DefaultTransactionSizeLimit),
}
}
// TearDownTestDatabase from PersistenceTestCluster interface
func (s *TestCluster) TearDownTestDatabase() {
s.DropDatabase()
}
// CreateDatabase from PersistenceTestCluster interface
func (s *TestCluster) CreateDatabase() {
cfg2 := s.cfg
// NOTE need to connect with empty name to create new database
if cfg2.PluginName != "sqlite" {
cfg2.DatabaseName = ""
}
var db sqlplugin.AdminDB
var err error
err = backoff.ThrottleRetry(
func() error {
db, err = NewSQLAdminDB(sqlplugin.DbKindUnknown, &cfg2, resolver.NewNoopResolver(), log.NewTestLogger(), metrics.NoopMetricsHandler)
return err
},
backoff.NewExponentialRetryPolicy(time.Second).WithExpirationInterval(time.Minute),
nil,
)
if err != nil {
panic(err)
}
defer func() {
err := db.Close()
if err != nil {
panic(err)
}
}()
err = db.CreateDatabase(s.cfg.DatabaseName)
if err != nil {
panic(err)
}
s.logger.Info("created database", tag.NewStringTag("database", s.cfg.DatabaseName))
}
// DropDatabase from PersistenceTestCluster interface
func (s *TestCluster) DropDatabase() {
cfg2 := s.cfg
if cfg2.PluginName == "sqlite" && cfg2.DatabaseName != ":memory:" && cfg2.ConnectAttributes["mode"] != "memory" {
if len(cfg2.DatabaseName) > 3 { // 3 should mean not ., .., empty, or /
err := os.Remove(cfg2.DatabaseName)
if err != nil {
panic(err)
}
}
return
}
// NOTE need to connect with empty name to drop the database
cfg2.DatabaseName = ""
db, err := NewSQLAdminDB(sqlplugin.DbKindUnknown, &cfg2, resolver.NewNoopResolver(), log.NewTestLogger(), metrics.NoopMetricsHandler)
if err != nil {
panic(err)
}
defer func() {
err := db.Close()
if err != nil {
panic(err)
}
}()
err = db.DropDatabase(s.cfg.DatabaseName)
if err != nil {
panic(err)
}
s.logger.Info("dropped database", tag.NewStringTag("database", s.cfg.DatabaseName))
}
// LoadSchema from PersistenceTestCluster interface
func (s *TestCluster) LoadSchema(schemaFile string) {
statements, err := p.LoadAndSplitQuery([]string{schemaFile})
if err != nil {
s.logger.Fatal("LoadSchema", tag.Error(err))
}
var db sqlplugin.AdminDB
err = backoff.ThrottleRetry(
func() error {
db, err = NewSQLAdminDB(sqlplugin.DbKindUnknown, &s.cfg, resolver.NewNoopResolver(), log.NewTestLogger(), metrics.NoopMetricsHandler)
return err
},
backoff.NewExponentialRetryPolicy(time.Second).WithExpirationInterval(time.Minute),
nil,
)
if err != nil {
panic(err)
}
defer func() {
err := db.Close()
if err != nil {
panic(err)
}
}()
for _, stmt := range statements {
if err = db.Exec(stmt); err != nil {
s.logger.Fatal("LoadSchema", tag.Error(err))
}
}
s.logger.Info("loaded schema")
}