Prepare returns *PreparedStatement

conn.go

@@ -59,14 +59,14 @@ type Conn struct {
 	RuntimeParams      map[string]string // parameters that have been reported by the server
 	config             ConnConfig        // config used when establishing this connection
 	TxStatus           byte
-	preparedStatements map[string]*preparedStatement
+	preparedStatements map[string]*PreparedStatement
 	notifications      []*Notification
 	alive              bool
 	causeOfDeath       error
 	logger             log.Logger
 }
 
-type preparedStatement struct {
+type PreparedStatement struct {
 	Name              string
 	FieldDescriptions []FieldDescription
 	ParameterOids     []Oid
@@ -185,7 +185,7 @@ func Connect(config ConnConfig) (c *Conn, err error) {
 	c.bufSize = c.config.MsgBufSize
 	c.buf = bytes.NewBuffer(make([]byte, 0, c.bufSize))
 	c.RuntimeParams = make(map[string]string)
-	c.preparedStatements = make(map[string]*preparedStatement)
+	c.preparedStatements = make(map[string]*PreparedStatement)
 	c.alive = true
 
 	if config.TLSConfig != nil {
@@ -579,7 +579,7 @@ func (c *Conn) SelectValues(sql string, arguments ...interface{}) ([]interface{}
 
 // Prepare creates a prepared statement with name and sql. sql can contain placeholders
 // for bound parameters. These placeholders are referenced positional as $1, $2, etc.
-func (c *Conn) Prepare(name, sql string) (err error) {
+func (c *Conn) Prepare(name, sql string) (ps *PreparedStatement, err error) {
 	defer func() {
 		if err != nil {
 			c.logger.Error(fmt.Sprintf("Prepare `%s` as `%s` failed: %v", name, sql, err))
@@ -595,7 +595,7 @@ func (c *Conn) Prepare(name, sql string) (err error) {
 	binary.Write(buf, binary.BigEndian, int16(0))
 	err = c.txMsg('P', buf, false)
 	if err != nil {
-		return err
+		return nil, err
 	}
 
 	// describe
@@ -605,16 +605,16 @@ func (c *Conn) Prepare(name, sql string) (err error) {
 	buf.WriteByte(0)
 	err = c.txMsg('D', buf, false)
 	if err != nil {
-		return
+		return nil, err
 	}
 
 	// sync
 	err = c.txMsg('S', c.getBuf(), true)
 	if err != nil {
-		return err
+		return nil, err
 	}
 
-	ps := preparedStatement{Name: name}
+	ps = &PreparedStatement{Name: name}
 
 	var softErr error
 
@@ -623,7 +623,7 @@ func (c *Conn) Prepare(name, sql string) (err error) {
 		var r *MessageReader
 		t, r, err := c.rxMsg()
 		if err != nil {
-			return err
+			return nil, err
 		}
 
 		switch t {
@@ -641,8 +641,8 @@ func (c *Conn) Prepare(name, sql string) (err error) {
 		case noData:
 		case readyForQuery:
 			c.rxReadyForQuery(r)
-			c.preparedStatements[name] = &ps
+			c.preparedStatements[name] = ps
-			return softErr
+			return ps, softErr
 		default:
 			if e := c.processContextFreeMsg(t, r); e != nil && softErr == nil {
 				softErr = e
@@ -761,7 +761,7 @@ func (c *Conn) sendSimpleQuery(sql string, arguments ...interface{}) (err error)
 	return c.txMsg('Q', buf, true)
 }
 
-func (c *Conn) sendPreparedQuery(ps *preparedStatement, arguments ...interface{}) (err error) {
+func (c *Conn) sendPreparedQuery(ps *PreparedStatement, arguments ...interface{}) (err error) {
 	if len(ps.ParameterOids) != len(arguments) {
 		return fmt.Errorf("Prepared statement \"%v\" requires %d parameters, but %d were provided", ps.Name, len(ps.ParameterOids), len(arguments))
 	}

conn_test.go

@@ -520,7 +520,7 @@ func TestPrepare(t *testing.T) {
 	defer conn.Close()
 
 	testTranscode := func(sql string, value interface{}) {
-		if err = conn.Prepare("testTranscode", sql); err != nil {
+		if _, err = conn.Prepare("testTranscode", sql); err != nil {
 			t.Errorf("Unable to prepare statement: %v", err)
 			return
 		}
@@ -555,7 +555,7 @@ func TestPrepare(t *testing.T) {
 	// Ensure that unknown types are just treated as strings
 	testTranscode("select $1::point", "(0,0)")
 
-	if err = conn.Prepare("testByteSliceTranscode", "select $1::bytea"); err != nil {
+	if _, err = conn.Prepare("testByteSliceTranscode", "select $1::bytea"); err != nil {
 		t.Errorf("Unable to prepare statement: %v", err)
 		return
 	}
@@ -588,7 +588,7 @@ func TestPrepare(t *testing.T) {
 	}
 
 	mustExecute(t, conn, "create temporary table foo(id serial)")
-	if err = conn.Prepare("deleteFoo", "delete from foo"); err != nil {
+	if _, err = conn.Prepare("deleteFoo", "delete from foo"); err != nil {
 		t.Fatalf("Unable to prepare delete: %v", err)
 	}
 }
@@ -600,7 +600,7 @@ func TestPrepareFailure(t *testing.T) {
 	}
 	defer conn.Close()
 
-	if err = conn.Prepare("badSQL", "select foo"); err == nil {
+	if _, err = conn.Prepare("badSQL", "select foo"); err == nil {
 		t.Fatal("Prepare should have failed with syntax error")
 	}
 

helper_test.go

@@ -21,7 +21,7 @@ func getSharedConnection(t testing.TB) (c *pgx.Conn) {
 }
 
 func mustPrepare(t testing.TB, conn *pgx.Conn, name, sql string) {
-	if err := conn.Prepare(name, sql); err != nil {
+	if _, err := conn.Prepare(name, sql); err != nil {
 		t.Fatalf("Could not prepare %v: %v", name, err)
 	}
 }