1
0
Fork 0

Update docs

This commit is contained in:
Gregory Eremin 2020-07-28 00:12:19 +02:00
parent c0582f3c96
commit f86864db3f
5 changed files with 26 additions and 16 deletions

View File

@ -50,9 +50,9 @@ just like feature contributions.
Modified copy of [go-sql-driver/mysql](https://github.com/go-sql-driver/mysql) Modified copy of [go-sql-driver/mysql](https://github.com/go-sql-driver/mysql)
is included with this project. It was changed in order to expose certain low is included with this project. It was changed in order to expose certain low
level functions that are used to establish a slave connection and to remove level functions that allow to establish a connection manually and register as a
automatic driver registration because it will likely conflict with the original replica server and to remove automatic driver registration because it will
code when imported as a dependency. likely conflict with the original code when imported as a dependency.
### Licence ### Licence

2
go.mod
View File

@ -5,3 +5,5 @@ require (
github.com/google/go-cmp v0.3.1 github.com/google/go-cmp v0.3.1
github.com/juju/errors v0.0.0-20190930114154-d42613fe1ab9 github.com/juju/errors v0.0.0-20190930114154-d42613fe1ab9
) )
go 1.13

View File

@ -9,18 +9,24 @@ import (
"github.com/localhots/bocadillo/mysql/driver/internal/mysql" "github.com/localhots/bocadillo/mysql/driver/internal/mysql"
) )
// Conn is a slave connection used to issue a binlog dump command. // Conn is a connection used to issue a binlog dump command.
type Conn struct { type Conn struct {
conn *mysql.ExtendedConn conn *mysql.ExtendedConn
conf Config conf Config
} }
// Config contains slave connection configuration. It is passed to master upon // Config contains all the details necessary to establish a replica connection.
// registration.
type Config struct { type Config struct {
ServerID uint32 // File and offset describe current state.
// File is the name of the binary log file.
File string File string
// Offset is the binary offset of the first event in the binary log file,
// a starting point at which processing should begin.
Offset uint32 Offset uint32
// ServerID should be a unique replica server identifier (i guess).
ServerID uint32
// Hostname along with server ID is used to identify the replica server
// connection.
Hostname string Hostname string
} }
@ -29,13 +35,16 @@ const (
comRegisterSlave byte = 21 comRegisterSlave byte = 21
comBinlogDump byte = 18 comBinlogDump byte = 18
// Bytes // Result codes
resultOK byte = 0x00 resultOK byte = 0x00
resultEOF byte = 0xFE resultEOF byte = 0xFE
resultERR byte = 0xFF resultERR byte = 0xFF
) )
// Connect esablishes a new slave connection. // Connect esablishes a new database connection. It is a go-sql-driver
// connection with a few low level functions exposed and with a high level
// wrapper that allows to execute just a few commands that are required for
// operation.
func Connect(dsn string, conf Config) (*Conn, error) { func Connect(dsn string, conf Config) (*Conn, error) {
if conf.Hostname == "" { if conf.Hostname == "" {
name, err := os.Hostname() name, err := os.Hostname()
@ -62,8 +71,7 @@ func Connect(dsn string, conf Config) (*Conn, error) {
return &Conn{conn: extconn, conf: conf}, nil return &Conn{conn: extconn, conf: conf}, nil
} }
// ReadPacket reads next packet from the server and processes the first status // ReadPacket reads next packet from the server and peeks at the status byte.
// byte.
func (c *Conn) ReadPacket(ctx context.Context) ([]byte, error) { func (c *Conn) ReadPacket(ctx context.Context) ([]byte, error) {
data, err := c.conn.ReadPacket(ctx) data, err := c.conn.ReadPacket(ctx)
if err != nil { if err != nil {

View File

@ -36,7 +36,7 @@ func (c *ExtendedConn) Exec(query string) error {
return c.exec(query) return c.exec(query)
} }
// ReadPacket reads a packet from a given connection. // ReadPacket reads a packet from the connection.
func (c *ExtendedConn) ReadPacket(ctx context.Context) ([]byte, error) { func (c *ExtendedConn) ReadPacket(ctx context.Context) ([]byte, error) {
if dl, ok := ctx.Deadline(); ok { if dl, ok := ctx.Deadline(); ok {
dur := dl.Sub(time.Now()) dur := dl.Sub(time.Now())
@ -51,7 +51,7 @@ func (c *ExtendedConn) ReadPacket(ctx context.Context) ([]byte, error) {
return c.readPacket() return c.readPacket()
} }
// WritePacket writes a packet to a given connection. // WritePacket writes a packet to the connection.
func (c *ExtendedConn) WritePacket(p []byte) error { func (c *ExtendedConn) WritePacket(p []byte) error {
return c.writePacket(p) return c.writePacket(p)
} }

View File

@ -37,7 +37,7 @@ var (
func New(dsn string, sc driver.Config) (*Reader, error) { func New(dsn string, sc driver.Config) (*Reader, error) {
conn, err := driver.Connect(dsn, sc) conn, err := driver.Connect(dsn, sc)
if err != nil { if err != nil {
return nil, errors.Annotate(err, "establish slave connection") return nil, errors.Annotate(err, "establish connection")
} }
r := &Reader{ r := &Reader{
@ -53,7 +53,7 @@ func New(dsn string, sc driver.Config) (*Reader, error) {
return nil, errors.Annotate(err, "disable binlog checksum") return nil, errors.Annotate(err, "disable binlog checksum")
} }
if err := conn.RegisterSlave(); err != nil { if err := conn.RegisterSlave(); err != nil {
return nil, errors.Annotate(err, "register slave server") return nil, errors.Annotate(err, "register replica server")
} }
if err := conn.StartBinlogDump(); err != nil { if err := conn.StartBinlogDump(); err != nil {
return nil, errors.Annotate(err, "start binlog dump") return nil, errors.Annotate(err, "start binlog dump")