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gotosocial/vendor/github.com/jackc/pgx/v5/stdlib/sql.go

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// Package stdlib is the compatibility layer from pgx to database/sql.
//
// A database/sql connection can be established through sql.Open.
//
// db, err := sql.Open("pgx", "postgres://pgx_md5:secret@localhost:5432/pgx_test?sslmode=disable")
// if err != nil {
// return err
// }
//
// Or from a DSN string.
//
// db, err := sql.Open("pgx", "user=postgres password=secret host=localhost port=5432 database=pgx_test sslmode=disable")
// if err != nil {
// return err
// }
//
// Or a pgx.ConnConfig can be used to set configuration not accessible via connection string. In this case the
// pgx.ConnConfig must first be registered with the driver. This registration returns a connection string which is used
// with sql.Open.
//
// connConfig, _ := pgx.ParseConfig(os.Getenv("DATABASE_URL"))
// connConfig.Logger = myLogger
// connStr := stdlib.RegisterConnConfig(connConfig)
// db, _ := sql.Open("pgx", connStr)
//
// pgx uses standard PostgreSQL positional parameters in queries. e.g. $1, $2. It does not support named parameters.
//
// db.QueryRow("select * from users where id=$1", userID)
//
// (*sql.Conn) Raw() can be used to get a *pgx.Conn from the standard database/sql.DB connection pool. This allows
// operations that use pgx specific functionality.
//
// // Given db is a *sql.DB
// conn, err := db.Conn(context.Background())
// if err != nil {
// // handle error from acquiring connection from DB pool
// }
//
// err = conn.Raw(func(driverConn any) error {
// conn := driverConn.(*stdlib.Conn).Conn() // conn is a *pgx.Conn
// // Do pgx specific stuff with conn
// conn.CopyFrom(...)
// return nil
// })
// if err != nil {
// // handle error that occurred while using *pgx.Conn
// }
//
// # PostgreSQL Specific Data Types
//
// The pgtype package provides support for PostgreSQL specific types. *pgtype.Map.SQLScanner is an adapter that makes
// these types usable as a sql.Scanner.
//
// m := pgtype.NewMap()
// var a []int64
// err := db.QueryRow("select '{1,2,3}'::bigint[]").Scan(m.SQLScanner(&a))
package stdlib
import (
"context"
"database/sql"
"database/sql/driver"
"errors"
"fmt"
"io"
"math"
"math/rand"
"reflect"
"strconv"
"strings"
"sync"
"time"
"github.com/jackc/pgx/v5"
"github.com/jackc/pgx/v5/pgconn"
"github.com/jackc/pgx/v5/pgtype"
)
// Only intrinsic types should be binary format with database/sql.
var databaseSQLResultFormats pgx.QueryResultFormatsByOID
var pgxDriver *Driver
func init() {
pgxDriver = &Driver{
configs: make(map[string]*pgx.ConnConfig),
}
// if pgx driver was already registered by different pgx major version then we
// skip registration under the default name.
if !contains(sql.Drivers(), "pgx") {
sql.Register("pgx", pgxDriver)
}
sql.Register("pgx/v5", pgxDriver)
databaseSQLResultFormats = pgx.QueryResultFormatsByOID{
pgtype.BoolOID: 1,
pgtype.ByteaOID: 1,
pgtype.CIDOID: 1,
pgtype.DateOID: 1,
pgtype.Float4OID: 1,
pgtype.Float8OID: 1,
pgtype.Int2OID: 1,
pgtype.Int4OID: 1,
pgtype.Int8OID: 1,
pgtype.OIDOID: 1,
pgtype.TimestampOID: 1,
pgtype.TimestamptzOID: 1,
pgtype.XIDOID: 1,
}
}
// TODO replace by slices.Contains when experimental package will be merged to stdlib
// https://pkg.go.dev/golang.org/x/exp/slices#Contains
func contains(list []string, y string) bool {
for _, x := range list {
if x == y {
return true
}
}
return false
}
// OptionOpenDB options for configuring the driver when opening a new db pool.
type OptionOpenDB func(*connector)
// OptionBeforeConnect provides a callback for before connect. It is passed a shallow copy of the ConnConfig that will
// be used to connect, so only its immediate members should be modified.
func OptionBeforeConnect(bc func(context.Context, *pgx.ConnConfig) error) OptionOpenDB {
return func(dc *connector) {
dc.BeforeConnect = bc
}
}
// OptionAfterConnect provides a callback for after connect.
func OptionAfterConnect(ac func(context.Context, *pgx.Conn) error) OptionOpenDB {
return func(dc *connector) {
dc.AfterConnect = ac
}
}
// OptionResetSession provides a callback that can be used to add custom logic prior to executing a query on the
// connection if the connection has been used before.
// If ResetSessionFunc returns ErrBadConn error the connection will be discarded.
func OptionResetSession(rs func(context.Context, *pgx.Conn) error) OptionOpenDB {
return func(dc *connector) {
dc.ResetSession = rs
}
}
// RandomizeHostOrderFunc is a BeforeConnect hook that randomizes the host order in the provided connConfig, so that a
// new host becomes primary each time. This is useful to distribute connections for multi-master databases like
// CockroachDB. If you use this you likely should set https://golang.org/pkg/database/sql/#DB.SetConnMaxLifetime as well
// to ensure that connections are periodically rebalanced across your nodes.
func RandomizeHostOrderFunc(ctx context.Context, connConfig *pgx.ConnConfig) error {
if len(connConfig.Fallbacks) == 0 {
return nil
}
newFallbacks := append([]*pgconn.FallbackConfig{{
Host: connConfig.Host,
Port: connConfig.Port,
TLSConfig: connConfig.TLSConfig,
}}, connConfig.Fallbacks...)
rand.Shuffle(len(newFallbacks), func(i, j int) {
newFallbacks[i], newFallbacks[j] = newFallbacks[j], newFallbacks[i]
})
// Use the one that sorted last as the primary and keep the rest as the fallbacks
newPrimary := newFallbacks[len(newFallbacks)-1]
connConfig.Host = newPrimary.Host
connConfig.Port = newPrimary.Port
connConfig.TLSConfig = newPrimary.TLSConfig
connConfig.Fallbacks = newFallbacks[:len(newFallbacks)-1]
return nil
}
func GetConnector(config pgx.ConnConfig, opts ...OptionOpenDB) driver.Connector {
c := connector{
ConnConfig: config,
BeforeConnect: func(context.Context, *pgx.ConnConfig) error { return nil }, // noop before connect by default
AfterConnect: func(context.Context, *pgx.Conn) error { return nil }, // noop after connect by default
ResetSession: func(context.Context, *pgx.Conn) error { return nil }, // noop reset session by default
driver: pgxDriver,
}
for _, opt := range opts {
opt(&c)
}
return c
}
func OpenDB(config pgx.ConnConfig, opts ...OptionOpenDB) *sql.DB {
c := GetConnector(config, opts...)
return sql.OpenDB(c)
}
type connector struct {
pgx.ConnConfig
BeforeConnect func(context.Context, *pgx.ConnConfig) error // function to call before creation of every new connection
AfterConnect func(context.Context, *pgx.Conn) error // function to call after creation of every new connection
ResetSession func(context.Context, *pgx.Conn) error // function is called before a connection is reused
driver *Driver
}
// Connect implement driver.Connector interface
func (c connector) Connect(ctx context.Context) (driver.Conn, error) {
var (
err error
conn *pgx.Conn
)
// Create a shallow copy of the config, so that BeforeConnect can safely modify it
connConfig := c.ConnConfig
if err = c.BeforeConnect(ctx, &connConfig); err != nil {
return nil, err
}
if conn, err = pgx.ConnectConfig(ctx, &connConfig); err != nil {
return nil, err
}
if err = c.AfterConnect(ctx, conn); err != nil {
return nil, err
}
return &Conn{conn: conn, driver: c.driver, connConfig: connConfig, resetSessionFunc: c.ResetSession}, nil
}
// Driver implement driver.Connector interface
func (c connector) Driver() driver.Driver {
return c.driver
}
// GetDefaultDriver returns the driver initialized in the init function
// and used when the pgx driver is registered.
func GetDefaultDriver() driver.Driver {
return pgxDriver
}
type Driver struct {
configMutex sync.Mutex
configs map[string]*pgx.ConnConfig
sequence int
}
func (d *Driver) Open(name string) (driver.Conn, error) {
ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second) // Ensure eventual timeout
defer cancel()
connector, err := d.OpenConnector(name)
if err != nil {
return nil, err
}
return connector.Connect(ctx)
}
func (d *Driver) OpenConnector(name string) (driver.Connector, error) {
return &driverConnector{driver: d, name: name}, nil
}
func (d *Driver) registerConnConfig(c *pgx.ConnConfig) string {
d.configMutex.Lock()
connStr := fmt.Sprintf("registeredConnConfig%d", d.sequence)
d.sequence++
d.configs[connStr] = c
d.configMutex.Unlock()
return connStr
}
func (d *Driver) unregisterConnConfig(connStr string) {
d.configMutex.Lock()
delete(d.configs, connStr)
d.configMutex.Unlock()
}
type driverConnector struct {
driver *Driver
name string
}
func (dc *driverConnector) Connect(ctx context.Context) (driver.Conn, error) {
var connConfig *pgx.ConnConfig
dc.driver.configMutex.Lock()
connConfig = dc.driver.configs[dc.name]
dc.driver.configMutex.Unlock()
if connConfig == nil {
var err error
connConfig, err = pgx.ParseConfig(dc.name)
if err != nil {
return nil, err
}
}
conn, err := pgx.ConnectConfig(ctx, connConfig)
if err != nil {
return nil, err
}
c := &Conn{
conn: conn,
driver: dc.driver,
connConfig: *connConfig,
resetSessionFunc: func(context.Context, *pgx.Conn) error { return nil },
}
return c, nil
}
func (dc *driverConnector) Driver() driver.Driver {
return dc.driver
}
// RegisterConnConfig registers a ConnConfig and returns the connection string to use with Open.
func RegisterConnConfig(c *pgx.ConnConfig) string {
return pgxDriver.registerConnConfig(c)
}
// UnregisterConnConfig removes the ConnConfig registration for connStr.
func UnregisterConnConfig(connStr string) {
pgxDriver.unregisterConnConfig(connStr)
}
type Conn struct {
conn *pgx.Conn
psCount int64 // Counter used for creating unique prepared statement names
driver *Driver
connConfig pgx.ConnConfig
resetSessionFunc func(context.Context, *pgx.Conn) error // Function is called before a connection is reused
lastResetSessionTime time.Time
}
// Conn returns the underlying *pgx.Conn
func (c *Conn) Conn() *pgx.Conn {
return c.conn
}
func (c *Conn) Prepare(query string) (driver.Stmt, error) {
return c.PrepareContext(context.Background(), query)
}
func (c *Conn) PrepareContext(ctx context.Context, query string) (driver.Stmt, error) {
if c.conn.IsClosed() {
return nil, driver.ErrBadConn
}
name := fmt.Sprintf("pgx_%d", c.psCount)
c.psCount++
sd, err := c.conn.Prepare(ctx, name, query)
if err != nil {
return nil, err
}
return &Stmt{sd: sd, conn: c}, nil
}
func (c *Conn) Close() error {
ctx, cancel := context.WithTimeout(context.Background(), time.Second*5)
defer cancel()
return c.conn.Close(ctx)
}
func (c *Conn) Begin() (driver.Tx, error) {
return c.BeginTx(context.Background(), driver.TxOptions{})
}
func (c *Conn) BeginTx(ctx context.Context, opts driver.TxOptions) (driver.Tx, error) {
if c.conn.IsClosed() {
return nil, driver.ErrBadConn
}
var pgxOpts pgx.TxOptions
switch sql.IsolationLevel(opts.Isolation) {
case sql.LevelDefault:
case sql.LevelReadUncommitted:
pgxOpts.IsoLevel = pgx.ReadUncommitted
case sql.LevelReadCommitted:
pgxOpts.IsoLevel = pgx.ReadCommitted
case sql.LevelRepeatableRead, sql.LevelSnapshot:
pgxOpts.IsoLevel = pgx.RepeatableRead
case sql.LevelSerializable:
pgxOpts.IsoLevel = pgx.Serializable
default:
return nil, fmt.Errorf("unsupported isolation: %v", opts.Isolation)
}
if opts.ReadOnly {
pgxOpts.AccessMode = pgx.ReadOnly
}
tx, err := c.conn.BeginTx(ctx, pgxOpts)
if err != nil {
return nil, err
}
return wrapTx{ctx: ctx, tx: tx}, nil
}
func (c *Conn) ExecContext(ctx context.Context, query string, argsV []driver.NamedValue) (driver.Result, error) {
if c.conn.IsClosed() {
return nil, driver.ErrBadConn
}
args := namedValueToInterface(argsV)
commandTag, err := c.conn.Exec(ctx, query, args...)
// if we got a network error before we had a chance to send the query, retry
if err != nil {
if pgconn.SafeToRetry(err) {
return nil, driver.ErrBadConn
}
}
return driver.RowsAffected(commandTag.RowsAffected()), err
}
func (c *Conn) QueryContext(ctx context.Context, query string, argsV []driver.NamedValue) (driver.Rows, error) {
if c.conn.IsClosed() {
return nil, driver.ErrBadConn
}
args := []any{databaseSQLResultFormats}
args = append(args, namedValueToInterface(argsV)...)
rows, err := c.conn.Query(ctx, query, args...)
if err != nil {
if pgconn.SafeToRetry(err) {
return nil, driver.ErrBadConn
}
return nil, err
}
// Preload first row because otherwise we won't know what columns are available when database/sql asks.
more := rows.Next()
if err = rows.Err(); err != nil {
rows.Close()
return nil, err
}
return &Rows{conn: c, rows: rows, skipNext: true, skipNextMore: more}, nil
}
func (c *Conn) Ping(ctx context.Context) error {
if c.conn.IsClosed() {
return driver.ErrBadConn
}
err := c.conn.Ping(ctx)
if err != nil {
// A Ping failure implies some sort of fatal state. The connection is almost certainly already closed by the
// failure, but manually close it just to be sure.
c.Close()
return driver.ErrBadConn
}
return nil
}
func (c *Conn) CheckNamedValue(*driver.NamedValue) error {
// Underlying pgx supports sql.Scanner and driver.Valuer interfaces natively. So everything can be passed through directly.
return nil
}
func (c *Conn) ResetSession(ctx context.Context) error {
if c.conn.IsClosed() {
return driver.ErrBadConn
}
now := time.Now()
if now.Sub(c.lastResetSessionTime) > time.Second {
if err := c.conn.PgConn().CheckConn(); err != nil {
return driver.ErrBadConn
}
}
c.lastResetSessionTime = now
return c.resetSessionFunc(ctx, c.conn)
}
type Stmt struct {
sd *pgconn.StatementDescription
conn *Conn
}
func (s *Stmt) Close() error {
ctx, cancel := context.WithTimeout(context.Background(), time.Second*5)
defer cancel()
return s.conn.conn.Deallocate(ctx, s.sd.Name)
}
func (s *Stmt) NumInput() int {
return len(s.sd.ParamOIDs)
}
func (s *Stmt) Exec(argsV []driver.Value) (driver.Result, error) {
return nil, errors.New("Stmt.Exec deprecated and not implemented")
}
func (s *Stmt) ExecContext(ctx context.Context, argsV []driver.NamedValue) (driver.Result, error) {
return s.conn.ExecContext(ctx, s.sd.Name, argsV)
}
func (s *Stmt) Query(argsV []driver.Value) (driver.Rows, error) {
return nil, errors.New("Stmt.Query deprecated and not implemented")
}
func (s *Stmt) QueryContext(ctx context.Context, argsV []driver.NamedValue) (driver.Rows, error) {
return s.conn.QueryContext(ctx, s.sd.Name, argsV)
}
type rowValueFunc func(src []byte) (driver.Value, error)
type Rows struct {
conn *Conn
rows pgx.Rows
valueFuncs []rowValueFunc
skipNext bool
skipNextMore bool
columnNames []string
}
func (r *Rows) Columns() []string {
if r.columnNames == nil {
fields := r.rows.FieldDescriptions()
r.columnNames = make([]string, len(fields))
for i, fd := range fields {
r.columnNames[i] = string(fd.Name)
}
}
return r.columnNames
}
// ColumnTypeDatabaseTypeName returns the database system type name. If the name is unknown the OID is returned.
func (r *Rows) ColumnTypeDatabaseTypeName(index int) string {
if dt, ok := r.conn.conn.TypeMap().TypeForOID(r.rows.FieldDescriptions()[index].DataTypeOID); ok {
return strings.ToUpper(dt.Name)
}
return strconv.FormatInt(int64(r.rows.FieldDescriptions()[index].DataTypeOID), 10)
}
const varHeaderSize = 4
// ColumnTypeLength returns the length of the column type if the column is a
// variable length type. If the column is not a variable length type ok
// should return false.
func (r *Rows) ColumnTypeLength(index int) (int64, bool) {
fd := r.rows.FieldDescriptions()[index]
switch fd.DataTypeOID {
case pgtype.TextOID, pgtype.ByteaOID:
return math.MaxInt64, true
case pgtype.VarcharOID, pgtype.BPCharArrayOID:
return int64(fd.TypeModifier - varHeaderSize), true
default:
return 0, false
}
}
// ColumnTypePrecisionScale should return the precision and scale for decimal
// types. If not applicable, ok should be false.
func (r *Rows) ColumnTypePrecisionScale(index int) (precision, scale int64, ok bool) {
fd := r.rows.FieldDescriptions()[index]
switch fd.DataTypeOID {
case pgtype.NumericOID:
mod := fd.TypeModifier - varHeaderSize
precision = int64((mod >> 16) & 0xffff)
scale = int64(mod & 0xffff)
return precision, scale, true
default:
return 0, 0, false
}
}
// ColumnTypeScanType returns the value type that can be used to scan types into.
func (r *Rows) ColumnTypeScanType(index int) reflect.Type {
fd := r.rows.FieldDescriptions()[index]
switch fd.DataTypeOID {
case pgtype.Float8OID:
return reflect.TypeOf(float64(0))
case pgtype.Float4OID:
return reflect.TypeOf(float32(0))
case pgtype.Int8OID:
return reflect.TypeOf(int64(0))
case pgtype.Int4OID:
return reflect.TypeOf(int32(0))
case pgtype.Int2OID:
return reflect.TypeOf(int16(0))
case pgtype.BoolOID:
return reflect.TypeOf(false)
case pgtype.NumericOID:
return reflect.TypeOf(float64(0))
case pgtype.DateOID, pgtype.TimestampOID, pgtype.TimestamptzOID:
return reflect.TypeOf(time.Time{})
case pgtype.ByteaOID:
return reflect.TypeOf([]byte(nil))
default:
return reflect.TypeOf("")
}
}
func (r *Rows) Close() error {
r.rows.Close()
return r.rows.Err()
}
func (r *Rows) Next(dest []driver.Value) error {
m := r.conn.conn.TypeMap()
fieldDescriptions := r.rows.FieldDescriptions()
if r.valueFuncs == nil {
r.valueFuncs = make([]rowValueFunc, len(fieldDescriptions))
for i, fd := range fieldDescriptions {
dataTypeOID := fd.DataTypeOID
format := fd.Format
switch fd.DataTypeOID {
case pgtype.BoolOID:
var d bool
scanPlan := m.PlanScan(dataTypeOID, format, &d)
r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
err := scanPlan.Scan(src, &d)
return d, err
}
case pgtype.ByteaOID:
var d []byte
scanPlan := m.PlanScan(dataTypeOID, format, &d)
r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
err := scanPlan.Scan(src, &d)
return d, err
}
case pgtype.CIDOID, pgtype.OIDOID, pgtype.XIDOID:
var d pgtype.Uint32
scanPlan := m.PlanScan(dataTypeOID, format, &d)
r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
err := scanPlan.Scan(src, &d)
if err != nil {
return nil, err
}
return d.Value()
}
case pgtype.DateOID:
var d pgtype.Date
scanPlan := m.PlanScan(dataTypeOID, format, &d)
r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
err := scanPlan.Scan(src, &d)
if err != nil {
return nil, err
}
return d.Value()
}
case pgtype.Float4OID:
var d float32
scanPlan := m.PlanScan(dataTypeOID, format, &d)
r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
err := scanPlan.Scan(src, &d)
return float64(d), err
}
case pgtype.Float8OID:
var d float64
scanPlan := m.PlanScan(dataTypeOID, format, &d)
r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
err := scanPlan.Scan(src, &d)
return d, err
}
case pgtype.Int2OID:
var d int16
scanPlan := m.PlanScan(dataTypeOID, format, &d)
r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
err := scanPlan.Scan(src, &d)
return int64(d), err
}
case pgtype.Int4OID:
var d int32
scanPlan := m.PlanScan(dataTypeOID, format, &d)
r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
err := scanPlan.Scan(src, &d)
return int64(d), err
}
case pgtype.Int8OID:
var d int64
scanPlan := m.PlanScan(dataTypeOID, format, &d)
r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
err := scanPlan.Scan(src, &d)
return d, err
}
case pgtype.JSONOID, pgtype.JSONBOID:
var d []byte
scanPlan := m.PlanScan(dataTypeOID, format, &d)
r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
err := scanPlan.Scan(src, &d)
if err != nil {
return nil, err
}
return d, nil
}
case pgtype.TimestampOID:
var d pgtype.Timestamp
scanPlan := m.PlanScan(dataTypeOID, format, &d)
r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
err := scanPlan.Scan(src, &d)
if err != nil {
return nil, err
}
return d.Value()
}
case pgtype.TimestamptzOID:
var d pgtype.Timestamptz
scanPlan := m.PlanScan(dataTypeOID, format, &d)
r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
err := scanPlan.Scan(src, &d)
if err != nil {
return nil, err
}
return d.Value()
}
default:
var d string
scanPlan := m.PlanScan(dataTypeOID, format, &d)
r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
err := scanPlan.Scan(src, &d)
return d, err
}
}
}
}
var more bool
if r.skipNext {
more = r.skipNextMore
r.skipNext = false
} else {
more = r.rows.Next()
}
if !more {
if r.rows.Err() == nil {
return io.EOF
} else {
return r.rows.Err()
}
}
for i, rv := range r.rows.RawValues() {
if rv != nil {
var err error
dest[i], err = r.valueFuncs[i](rv)
if err != nil {
return fmt.Errorf("convert field %d failed: %v", i, err)
}
} else {
dest[i] = nil
}
}
return nil
}
func valueToInterface(argsV []driver.Value) []any {
args := make([]any, 0, len(argsV))
for _, v := range argsV {
if v != nil {
args = append(args, v.(any))
} else {
args = append(args, nil)
}
}
return args
}
func namedValueToInterface(argsV []driver.NamedValue) []any {
args := make([]any, 0, len(argsV))
for _, v := range argsV {
if v.Value != nil {
args = append(args, v.Value.(any))
} else {
args = append(args, nil)
}
}
return args
}
type wrapTx struct {
ctx context.Context
tx pgx.Tx
}
func (wtx wrapTx) Commit() error { return wtx.tx.Commit(wtx.ctx) }
func (wtx wrapTx) Rollback() error { return wtx.tx.Rollback(wtx.ctx) }