Add crdbpgxv5 for supporting github.com/jackc/pgx/v5

Author: MoinTom

crdb/crdbpgx/README.md

@@ -1,7 +1,9 @@
 `crdbpgx` is a wrapper around the logic for issuing SQL transactions which
 performs retries (as required by CockroachDB) when using
 [`github.com/jackc/pgx`](https://github.com/jackc/pgx) in standalone-library
-mode. pgx versions below v4 are not supported.
+mode. pgx versions below v4 are not supported. 
+
+Note: use `crdbpgxv5` for `pgx/v5` support  
 
 If you're using pgx just as a driver for the standard `database/sql` package,
 use the parent `crdb` package instead.

crdb/crdbpgxv5/README.md

@@ -0,0 +1,9 @@
+`crdbpgxv5` is a wrapper around the logic for issuing SQL transactions which
+performs retries (as required by CockroachDB) when using
+[`github.com/jackc/pgx`](https://github.com/jackc/pgx) in standalone-library
+mode. `crdbpgxv5` only supports `pgx/v5`.
+
+Note: use `crdbpgx` for `pgx/v4` support
+
+If you're using pgx just as a driver for the standard `database/sql` package,
+use the parent `crdb` package instead.

crdb/crdbpgxv5/pgx.go

@@ -0,0 +1,65 @@
+// Copyright 2022 The Cockroach Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+// implied. See the License for the specific language governing
+// permissions and limitations under the License.
+
+package crdbpgx
+
+import (
+	"context"
+	"github.com/jackc/pgx/v5"
+
+	"github.com/cockroachdb/cockroach-go/v2/crdb"
+)
+
+// ExecuteTx runs fn inside a transaction and retries it as needed. On
+// non-retryable failures, the transaction is aborted and rolled back; on
+// success, the transaction is committed.
+//
+// See crdb.ExecuteTx() for more information.
+//
+// conn can be a pgx.Conn or a pgxpool.Pool.
+func ExecuteTx(
+	ctx context.Context, conn Conn, txOptions pgx.TxOptions, fn func(pgx.Tx) error,
+) error {
+	tx, err := conn.BeginTx(ctx, txOptions)
+	if err != nil {
+		return err
+	}
+	return crdb.ExecuteInTx(ctx, pgxTxAdapter{tx}, func() error { return fn(tx) })
+}
+
+// Conn abstracts pgx transactions creators: pgx.Conn and pgxpool.Pool.
+type Conn interface {
+	Begin(context.Context) (pgx.Tx, error)
+	BeginTx(context.Context, pgx.TxOptions) (pgx.Tx, error)
+}
+
+type pgxTxAdapter struct {
+	tx pgx.Tx
+}
+
+var _ crdb.Tx = pgxTxAdapter{}
+
+func (tx pgxTxAdapter) Commit(ctx context.Context) error {
+	return tx.tx.Commit(ctx)
+}
+
+func (tx pgxTxAdapter) Rollback(ctx context.Context) error {
+	return tx.tx.Rollback(ctx)
+}
+
+// Exec is part of the crdb.Tx interface.
+func (tx pgxTxAdapter) Exec(ctx context.Context, q string, args ...interface{}) error {
+	_, err := tx.tx.Exec(ctx, q, args...)
+	return err
+}

crdb/crdbpgxv5/pgx_test.go

@@ -0,0 +1,100 @@
+// Copyright 2022 The Cockroach Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+// implied. See the License for the specific language governing
+// permissions and limitations under the License.
+
+package crdbpgx
+
+import (
+	"context"
+	"fmt"
+	"github.com/jackc/pgx/v5"
+	"github.com/jackc/pgx/v5/pgxpool"
+	"testing"
+
+	"github.com/cockroachdb/cockroach-go/v2/crdb"
+	"github.com/cockroachdb/cockroach-go/v2/testserver"
+)
+
+// TestExecuteTx verifies transaction retry using the classic
+// example of write skew in bank account balance transfers.
+func TestExecuteTx(t *testing.T) {
+	ts, err := testserver.NewTestServer()
+	if err != nil {
+		t.Fatal(err)
+	}
+	ctx := context.Background()
+
+	pool, err := pgxpool.New(ctx, ts.PGURL().String())
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if err := crdb.ExecuteTxGenericTest(ctx, pgxWriteSkewTest{pool: pool}); err != nil {
+		t.Fatal(err)
+	}
+}
+
+type pgxWriteSkewTest struct {
+	pool *pgxpool.Pool
+}
+
+func (t pgxWriteSkewTest) Init(ctx context.Context) error {
+	initStmt := `
+CREATE DATABASE d;
+CREATE TABLE d.t (acct INT PRIMARY KEY, balance INT);
+INSERT INTO d.t (acct, balance) VALUES (1, 100), (2, 100);
+`
+	_, err := t.pool.Exec(ctx, initStmt)
+	return err
+}
+
+var _ crdb.WriteSkewTest = pgxWriteSkewTest{}
+
+// ExecuteTx is part of the crdb.WriteSkewTest interface.
+func (t pgxWriteSkewTest) ExecuteTx(ctx context.Context, fn func(tx interface{}) error) error {
+	return ExecuteTx(ctx, t.pool, pgx.TxOptions{}, func(tx pgx.Tx) error {
+		return fn(tx)
+	})
+}
+
+// GetBalances is part of the crdb.WriteSkewTest interface.
+func (t pgxWriteSkewTest) GetBalances(ctx context.Context, txi interface{}) (int, int, error) {
+	tx := txi.(pgx.Tx)
+	var rows pgx.Rows
+	rows, err := tx.Query(ctx, `SELECT balance FROM d.t WHERE acct IN (1, 2);`)
+	if err != nil {
+		return 0, 0, err
+	}
+	defer rows.Close()
+	var bal1, bal2 int
+	balances := []*int{&bal1, &bal2}
+	i := 0
+	for ; rows.Next(); i++ {
+		if err = rows.Scan(balances[i]); err != nil {
+			return 0, 0, err
+		}
+	}
+	if i != 2 {
+		return 0, 0, fmt.Errorf("expected two balances; got %d", i)
+	}
+	return bal1, bal2, nil
+}
+
+// UpdateBalance is part of the crdb.WriteSkewInterface.
+func (t pgxWriteSkewTest) UpdateBalance(
+	ctx context.Context, txi interface{}, acct, delta int,
+) error {
+	tx := txi.(pgx.Tx)
+	_, err := tx.Exec(ctx, `UPDATE d.t SET balance=balance+$1 WHERE acct=$2;`, delta, acct)
+	return err
+}

go.mod

@@ -5,13 +5,13 @@ go 1.13
 require (
 	github.com/gofrs/flock v0.8.1
 	github.com/jackc/pgx/v4 v4.16.1
+	github.com/jackc/pgx/v5 v5.2.0
 	github.com/jmoiron/sqlx v1.3.5
 	github.com/lib/pq v1.10.6
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/shopspring/decimal v1.3.1 // indirect
-	github.com/stretchr/testify v1.7.0
-	golang.org/x/crypto v0.0.0-20220517005047-85d78b3ac167 // indirect
-	golang.org/x/sys v0.0.0-20220513210249-45d2b4557a2a // indirect
+	github.com/stretchr/testify v1.8.1
 	gorm.io/driver/postgres v1.3.5
 	gorm.io/gorm v1.23.5
 )
+