mirror of
https://github.com/hanzoai/tasks.git
synced 2026-10-04 02:04:03 +00:00
Tim Deeb-SwihartandGitHub
be7b5514a5
## 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?
122 lines
3.2 KiB
Go
122 lines
3.2 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 postgresql
|
|
|
|
import (
|
|
"context"
|
|
"database/sql"
|
|
|
|
"go.temporal.io/server/common/persistence/sql/sqlplugin"
|
|
)
|
|
|
|
const (
|
|
createShardQry = `INSERT INTO
|
|
shards (shard_id, range_id, data, data_encoding) VALUES ($1, $2, $3, $4)`
|
|
|
|
getShardQry = `SELECT
|
|
shard_id, range_id, data, data_encoding
|
|
FROM shards WHERE shard_id = $1`
|
|
|
|
updateShardQry = `UPDATE shards
|
|
SET range_id = $1, data = $2, data_encoding = $3
|
|
WHERE shard_id = $4`
|
|
|
|
lockShardQry = `SELECT range_id FROM shards WHERE shard_id = $1 FOR UPDATE`
|
|
readLockShardQry = `SELECT range_id FROM shards WHERE shard_id = $1 FOR SHARE`
|
|
)
|
|
|
|
// InsertIntoShards inserts one or more rows into shards table
|
|
func (pdb *db) InsertIntoShards(
|
|
ctx context.Context,
|
|
row *sqlplugin.ShardsRow,
|
|
) (sql.Result, error) {
|
|
return pdb.ExecContext(ctx,
|
|
createShardQry,
|
|
row.ShardID,
|
|
row.RangeID,
|
|
row.Data,
|
|
row.DataEncoding,
|
|
)
|
|
}
|
|
|
|
// UpdateShards updates one or more rows into shards table
|
|
func (pdb *db) UpdateShards(
|
|
ctx context.Context,
|
|
row *sqlplugin.ShardsRow,
|
|
) (sql.Result, error) {
|
|
return pdb.ExecContext(ctx,
|
|
updateShardQry,
|
|
row.RangeID,
|
|
row.Data,
|
|
row.DataEncoding,
|
|
row.ShardID,
|
|
)
|
|
}
|
|
|
|
// SelectFromShards reads one or more rows from shards table
|
|
func (pdb *db) SelectFromShards(
|
|
ctx context.Context,
|
|
filter sqlplugin.ShardsFilter,
|
|
) (*sqlplugin.ShardsRow, error) {
|
|
var row sqlplugin.ShardsRow
|
|
err := pdb.GetContext(ctx,
|
|
&row,
|
|
getShardQry,
|
|
filter.ShardID,
|
|
)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &row, nil
|
|
}
|
|
|
|
// ReadLockShards acquires a read lock on a single row in shards table
|
|
func (pdb *db) ReadLockShards(
|
|
ctx context.Context,
|
|
filter sqlplugin.ShardsFilter,
|
|
) (int64, error) {
|
|
var rangeID int64
|
|
err := pdb.GetContext(ctx,
|
|
&rangeID,
|
|
readLockShardQry,
|
|
filter.ShardID,
|
|
)
|
|
return rangeID, err
|
|
}
|
|
|
|
// WriteLockShards acquires a write lock on a single row in shards table
|
|
func (pdb *db) WriteLockShards(
|
|
ctx context.Context,
|
|
filter sqlplugin.ShardsFilter,
|
|
) (int64, error) {
|
|
var rangeID int64
|
|
err := pdb.GetContext(ctx,
|
|
&rangeID,
|
|
lockShardQry,
|
|
filter.ShardID,
|
|
)
|
|
return rangeID, err
|
|
}
|