GOMODULES
/
pgx
mirror of https://github.com/jackc/pgx.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Use higher pgconn.FieldDescription with string Name 

Instead of using pgproto3.FieldDescription through pgconn and pgx. This
lets the lowest level pgproto3 still be as memory efficient as possible.

https://github.com/jackc/pgx/pull/1281
v5-dev
Jack Christensen 2022-08-20 09:54:30 -05:00
parent dbee461dc9
commit ae65a8007b
5 changed files with 66 additions and 37 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

61
pgconn/pgconn.go
View File

@ -83,6 +83,7 @@ type PgConn struct {
multiResultReader MultiResultReader
pipeline Pipeline
contextWatcher *ctxwatch.ContextWatcher
fieldDescriptions [16]FieldDescription
cleanupDone chan struct{}
}
@ -526,9 +527,10 @@ func (pgConn *PgConn) PID() uint32 {
// TxStatus returns the current TxStatus as reported by the server in the ReadyForQuery message.
//
// Possible return values:
// 'I' - idle / not in transaction
// 'T' - in a transaction
// 'E' - in a failed transaction
//
// 'I' - idle / not in transaction
// 'T' - in a transaction
// 'E' - in a failed transaction
//
// See https://www.postgresql.org/docs/current/protocol-message-formats.html.
func (pgConn *PgConn) TxStatus() byte {
@ -714,11 +716,41 @@ func (ct CommandTag) Select() bool {
return strings.HasPrefix(ct.s, "SELECT")
}
type FieldDescription struct {
Name string
TableOID uint32
TableAttributeNumber uint16
DataTypeOID uint32
DataTypeSize int16
TypeModifier int32
Format int16
}
func (pgConn *PgConn) convertRowDescription(dst []FieldDescription, rd *pgproto3.RowDescription) []FieldDescription {
if cap(dst) >= len(rd.Fields) {
dst = dst[:len(rd.Fields):len(rd.Fields)]
} else {
dst = make([]FieldDescription, len(rd.Fields))
}
for i := range rd.Fields {
dst[i].Name = string(rd.Fields[i].Name)
dst[i].TableOID = rd.Fields[i].TableOID
dst[i].TableAttributeNumber = rd.Fields[i].TableAttributeNumber
dst[i].DataTypeOID = rd.Fields[i].DataTypeOID
dst[i].DataTypeSize = rd.Fields[i].DataTypeSize
dst[i].TypeModifier = rd.Fields[i].TypeModifier
dst[i].Format = rd.Fields[i].Format
}
return dst
}
type StatementDescription struct {
Name string
SQL string
ParamOIDs []uint32
Fields []pgproto3.FieldDescription
Fields []FieldDescription
}
// Prepare creates a prepared statement. If the name is empty, the anonymous prepared statement will be used. This
@ -765,8 +797,7 @@ readloop:
psd.ParamOIDs = make([]uint32, len(msg.ParameterOIDs))
copy(psd.ParamOIDs, msg.ParameterOIDs)
case *pgproto3.RowDescription:
psd.Fields = make([]pgproto3.FieldDescription, len(msg.Fields))
copy(psd.Fields, msg.Fields)
psd.Fields = pgConn.convertRowDescription(nil, msg)
case *pgproto3.ErrorResponse:
parseErr = ErrorResponseToPgError(msg)
case *pgproto3.ReadyForQuery:
@ -1281,8 +1312,9 @@ func (mrr *MultiResultReader) NextResult() bool {
pgConn: mrr.pgConn,
multiResultReader: mrr,
ctx: mrr.ctx,
fieldDescriptions: msg.Fields,
fieldDescriptions: mrr.pgConn.convertRowDescription(mrr.pgConn.fieldDescriptions[:], msg),
}
mrr.rr = &mrr.pgConn.resultReader
return true
case *pgproto3.CommandComplete:
@ -1325,7 +1357,7 @@ type ResultReader struct {
pipeline *Pipeline
ctx context.Context
fieldDescriptions []pgproto3.FieldDescription
fieldDescriptions []FieldDescription
rowValues [][]byte
commandTag CommandTag
commandConcluded bool
@ -1335,7 +1367,7 @@ type ResultReader struct {
// Result is the saved query response that is returned by calling Read on a ResultReader.
type Result struct {
FieldDescriptions []pgproto3.FieldDescription
FieldDescriptions []FieldDescription
Rows [][][]byte
CommandTag CommandTag
Err error
@ -1347,7 +1379,7 @@ func (rr *ResultReader) Read() *Result {
for rr.NextRow() {
if br.FieldDescriptions == nil {
br.FieldDescriptions = make([]pgproto3.FieldDescription, len(rr.FieldDescriptions()))
br.FieldDescriptions = make([]FieldDescription, len(rr.FieldDescriptions()))
copy(br.FieldDescriptions, rr.FieldDescriptions())
}
@ -1385,7 +1417,7 @@ func (rr *ResultReader) NextRow() bool {
// FieldDescriptions returns the field descriptions for the current result set. The returned slice is only valid until
// the ResultReader is closed.
func (rr *ResultReader) FieldDescriptions() []pgproto3.FieldDescription {
func (rr *ResultReader) FieldDescriptions() []FieldDescription {
return rr.fieldDescriptions
}
@ -1473,7 +1505,7 @@ func (rr *ResultReader) receiveMessage() (msg pgproto3.BackendMessage, err error
switch msg := msg.(type) {
case *pgproto3.RowDescription:
rr.fieldDescriptions = msg.Fields
rr.fieldDescriptions = rr.pgConn.convertRowDescription(rr.pgConn.fieldDescriptions[:], msg)
case *pgproto3.CommandComplete:
rr.concludeCommand(rr.pgConn.makeCommandTag(msg.CommandTag), nil)
case *pgproto3.EmptyQueryResponse:
@ -1825,7 +1857,7 @@ func (p *Pipeline) GetResults() (results any, err error) {
pgConn: p.conn,
pipeline: p,
ctx: p.ctx,
fieldDescriptions: msg.Fields,
fieldDescriptions: p.conn.convertRowDescription(p.conn.fieldDescriptions[:], msg),
}
return &p.conn.resultReader, nil
case *pgproto3.CommandComplete:
@ -1872,8 +1904,7 @@ func (p *Pipeline) getResultsPrepare() (*StatementDescription, error) {
psd.ParamOIDs = make([]uint32, len(msg.ParameterOIDs))
copy(psd.ParamOIDs, msg.ParameterOIDs)
case *pgproto3.RowDescription:
psd.Fields = make([]pgproto3.FieldDescription, len(msg.Fields))
copy(psd.Fields, msg.Fields)
psd.Fields = p.conn.convertRowDescription(nil, msg)
return psd, nil
// NoData is returned instead of RowDescription when there is no expected result. e.g. An INSERT without a RETURNING

10
pgconn/pgconn_test.go
View File

@ -642,13 +642,13 @@ func TestConnExecMultipleQueriesEagerFieldDescriptions(t *testing.T) {
require.True(t, mrr.NextResult())
require.Len(t, mrr.ResultReader().FieldDescriptions(), 1)
assert.Equal(t, []byte("msg"), mrr.ResultReader().FieldDescriptions()[0].Name)
assert.Equal(t, "msg", mrr.ResultReader().FieldDescriptions()[0].Name)
_, err = mrr.ResultReader().Close()
require.NoError(t, err)
require.True(t, mrr.NextResult())
require.Len(t, mrr.ResultReader().FieldDescriptions(), 1)
assert.Equal(t, []byte("num"), mrr.ResultReader().FieldDescriptions()[0].Name)
assert.Equal(t, "num", mrr.ResultReader().FieldDescriptions()[0].Name)
_, err = mrr.ResultReader().Close()
require.NoError(t, err)
@ -772,7 +772,7 @@ func TestConnExecParams(t *testing.T) {
result := pgConn.ExecParams(context.Background(), "select $1::text as msg", [][]byte{[]byte("Hello, world")}, nil, nil, nil)
require.Len(t, result.FieldDescriptions(), 1)
assert.Equal(t, []byte("msg"), result.FieldDescriptions()[0].Name)
assert.Equal(t, "msg", result.FieldDescriptions()[0].Name)
rowCount := 0
for result.NextRow() {
@ -937,7 +937,7 @@ func TestResultReaderValuesHaveSameCapacityAsLength(t *testing.T) {
result := pgConn.ExecParams(context.Background(), "select $1::text as msg", [][]byte{[]byte("Hello, world")}, nil, nil, nil)
require.Len(t, result.FieldDescriptions(), 1)
assert.Equal(t, []byte("msg"), result.FieldDescriptions()[0].Name)
assert.Equal(t, "msg", result.FieldDescriptions()[0].Name)
rowCount := 0
for result.NextRow() {
@ -968,7 +968,7 @@ func TestConnExecPrepared(t *testing.T) {
result := pgConn.ExecPrepared(context.Background(), "ps1", [][]byte{[]byte("Hello, world")}, nil, nil)
require.Len(t, result.FieldDescriptions(), 1)
assert.Equal(t, []byte("msg"), result.FieldDescriptions()[0].Name)
assert.Equal(t, "msg", result.FieldDescriptions()[0].Name)
rowCount := 0
for result.NextRow() {

21
pgxpool/rows.go
View File

@ -3,22 +3,21 @@ package pgxpool
import (
"github.com/jackc/pgx/v5"
"github.com/jackc/pgx/v5/pgconn"
"github.com/jackc/pgx/v5/pgproto3"
)
type errRows struct {
err error
}
func (errRows) Close() {}
func (e errRows) Err() error { return e.err }
func (errRows) CommandTag() pgconn.CommandTag { return pgconn.CommandTag{} }
func (errRows) FieldDescriptions() []pgproto3.FieldDescription { return nil }
func (errRows) Next() bool { return false }
func (e errRows) Scan(dest ...any) error { return e.err }
func (e errRows) Values() ([]any, error) { return nil, e.err }
func (e errRows) RawValues() [][]byte { return nil }
func (e errRows) Conn() *pgx.Conn { return nil }
func (errRows) Close() {}
func (e errRows) Err() error { return e.err }
func (errRows) CommandTag() pgconn.CommandTag { return pgconn.CommandTag{} }
func (errRows) FieldDescriptions() []pgconn.FieldDescription { return nil }
func (errRows) Next() bool { return false }
func (e errRows) Scan(dest ...any) error { return e.err }
func (e errRows) Values() ([]any, error) { return nil, e.err }
func (e errRows) RawValues() [][]byte { return nil }
func (e errRows) Conn() *pgx.Conn { return nil }
type errRow struct {
err error
@ -51,7 +50,7 @@ func (rows *poolRows) CommandTag() pgconn.CommandTag {
return rows.r.CommandTag()
}
func (rows *poolRows) FieldDescriptions() []pgproto3.FieldDescription {
func (rows *poolRows) FieldDescriptions() []pgconn.FieldDescription {
return rows.r.FieldDescriptions()
}

2
query_test.go
View File

@ -66,7 +66,7 @@ func TestConnQueryRowsFieldDescriptionsBeforeNext(t *testing.T) {
defer rows.Close()
require.Len(t, rows.FieldDescriptions(), 1)
assert.Equal(t, []byte("msg"), rows.FieldDescriptions()[0].Name)
assert.Equal(t, "msg", rows.FieldDescriptions()[0].Name)
}
func TestConnQueryWithoutResultSetCommandTag(t *testing.T) {

9
rows.go
View File

@ -9,7 +9,6 @@ import (
"github.com/jackc/pgx/v5/internal/stmtcache"
"github.com/jackc/pgx/v5/pgconn"
"github.com/jackc/pgx/v5/pgproto3"
"github.com/jackc/pgx/v5/pgtype"
)
@ -34,7 +33,7 @@ type Rows interface {
// CommandTag returns the command tag from this query. It is only available after Rows is closed.
CommandTag() pgconn.CommandTag
FieldDescriptions() []pgproto3.FieldDescription
FieldDescriptions() []pgconn.FieldDescription
// Next prepares the next row for reading. It returns true if there is another
// row and false if no more rows are available. It automatically closes rows
@ -135,7 +134,7 @@ type baseRows struct {
rowCount int
}
func (rows *baseRows) FieldDescriptions() []pgproto3.FieldDescription {
func (rows *baseRows) FieldDescriptions() []pgconn.FieldDescription {
return rows.resultReader.FieldDescriptions()
}
@ -337,7 +336,7 @@ func (e ScanArgError) Unwrap() error {
// fieldDescriptions - OID and format of values
// values - the raw data as returned from the PostgreSQL server
// dest - the destination that values will be decoded into
func ScanRow(typeMap *pgtype.Map, fieldDescriptions []pgproto3.FieldDescription, values [][]byte, dest ...any) error {
func ScanRow(typeMap *pgtype.Map, fieldDescriptions []pgconn.FieldDescription, values [][]byte, dest ...any) error {
if len(fieldDescriptions) != len(values) {
return fmt.Errorf("number of field descriptions must equal number of values, got %d and %d", len(fieldDescriptions), len(values))
}
@ -395,7 +394,7 @@ func ForEachRow(rows Rows, scans []any, fn func() error) (pgconn.CommandTag, err
// CollectableRow is the subset of Rows methods that a RowToFunc is allowed to call.
type CollectableRow interface {
FieldDescriptions() []pgproto3.FieldDescription
FieldDescriptions() []pgconn.FieldDescription
Scan(dest ...any) error
Values() ([]any, error)
RawValues() [][]byte