v/vlib/x/websocket/websocket_client.v

485 lines
13 KiB
V

// websocket module implements websocket client and a websocket server
// attribution: @thecoderr the author of original websocket client
[manualfree]
module websocket
import net
import x.openssl
import net.urllib
import time
import log
import rand
const (
empty_bytearr = []byte{} // used as empty response to avoid allocation
)
// Client represents websocket client
pub struct Client {
is_server bool
mut:
ssl_conn &openssl.SSLConn // secure connection used when wss is used
flags []Flag // flags used in handshake
fragments []Fragment // current fragments
message_callbacks []MessageEventHandler // all callbacks on_message
error_callbacks []ErrorEventHandler // all callbacks on_error
open_callbacks []OpenEventHandler // all callbacks on_open
close_callbacks []CloseEventHandler // all callbacks on_close
pub:
is_ssl bool // true if secure socket is used
uri Uri // uri of current connection
id string // unique id of client
pub mut:
conn &net.TcpConn // underlying TCP socket connection
nonce_size int = 16 // size of nounce used for masking
panic_on_callback bool // set to true of callbacks can panic
state State // current state of connection
logger &log.Log // logger used to log messages
resource_name string // name of current resource
last_pong_ut u64 // last time in unix time we got a pong message
}
// Flag represents different types of headers in websocket handshake
enum Flag {
has_accept // Webs
has_connection
has_upgrade
}
// State represents the state of the websocket connection.
enum State {
connecting = 0
open
closing
closed
}
// Message represents a whole message combined from 1 to n frames
pub struct Message {
pub:
opcode OPCode // websocket frame type of this message
payload []byte // payload of the message
}
// OPCode represents the supported websocket frame types
pub enum OPCode {
continuation = 0x00
text_frame = 0x01
binary_frame = 0x02
close = 0x08
ping = 0x09
pong = 0x0A
}
// new_client instance a new websocket client
pub fn new_client(address string) ?&Client {
uri := parse_uri(address) ?
return &Client{
conn: 0
is_server: false
ssl_conn: openssl.new_ssl_conn()
is_ssl: address.starts_with('wss')
logger: &log.Log{
level: .info
}
uri: uri
state: .closed
id: rand.uuid_v4()
}
}
// connect connects to remote websocket server
pub fn (mut ws Client) connect() ? {
ws.assert_not_connected() ?
ws.set_state(.connecting)
ws.logger.info('connecting to host $ws.uri')
ws.conn = ws.dial_socket() ?
// Todo: make setting configurable
ws.conn.set_read_timeout(time.second * 30)
ws.conn.set_write_timeout(time.second * 30)
ws.handshake() ?
ws.set_state(.open)
ws.logger.info('successfully connected to host $ws.uri')
ws.send_open_event()
}
// listen listens and processes incoming messages
pub fn (mut ws Client) listen() ? {
mut log := 'Starting client listener, server($ws.is_server)...'
ws.logger.info(log)
unsafe { log.free() }
defer {
ws.logger.info('Quit client listener, server($ws.is_server)...')
if ws.state == .open {
ws.close(1000, 'closed by client') or { }
}
}
for ws.state == .open {
msg := ws.read_next_message() or {
if ws.state in [.closed, .closing] {
return
}
ws.debug_log('failed to read next message: $err')
ws.send_error_event('failed to read next message: $err')
return err
}
if ws.state in [.closed, .closing] {
return
}
ws.debug_log('got message: $msg.opcode')
match msg.opcode {
.text_frame {
log = 'read: text'
ws.debug_log(log)
unsafe { log.free() }
ws.send_message_event(msg)
unsafe { msg.free() }
}
.binary_frame {
ws.debug_log('read: binary')
ws.send_message_event(msg)
unsafe { msg.free() }
}
.ping {
ws.debug_log('read: ping, sending pong')
ws.send_control_frame(.pong, 'PONG', msg.payload) or {
ws.logger.error('error in message callback sending PONG: $err')
ws.send_error_event('error in message callback sending PONG: $err')
if ws.panic_on_callback {
panic(err.msg)
}
continue
}
if msg.payload.len > 0 {
unsafe { msg.free() }
}
}
.pong {
ws.debug_log('read: pong')
ws.last_pong_ut = time.now().unix
ws.send_message_event(msg)
if msg.payload.len > 0 {
unsafe { msg.free() }
}
}
.close {
log = 'read: close'
ws.debug_log(log)
unsafe { log.free() }
defer {
ws.manage_clean_close()
}
if msg.payload.len > 0 {
if msg.payload.len == 1 {
ws.close(1002, 'close payload cannot be 1 byte') ?
return error('close payload cannot be 1 byte')
}
code := (int(msg.payload[0]) << 8) + int(msg.payload[1])
if code in invalid_close_codes {
ws.close(1002, 'invalid close code: $code') ?
return error('invalid close code: $code')
}
reason := if msg.payload.len > 2 { msg.payload[2..] } else { []byte{} }
if reason.len > 0 {
ws.validate_utf_8(.close, reason) ?
}
if ws.state !in [.closing, .closed] {
// sending close back according to spec
ws.debug_log('close with reason, code: $code, reason: $reason')
r := reason.bytestr()
ws.close(code, r) ?
}
unsafe { msg.free() }
} else {
if ws.state !in [.closing, .closed] {
ws.debug_log('close with reason, no code')
// sending close back according to spec
ws.close(1000, 'normal') ?
}
unsafe { msg.free() }
}
return
}
.continuation {
ws.logger.error('unexpected opcode continuation, nothing to continue')
ws.send_error_event('unexpected opcode continuation, nothing to continue')
ws.close(1002, 'nothing to continue') ?
return error('unexpected opcode continuation, nothing to continue')
}
}
}
}
// manage_clean_close closes connection in a clean websocket way
fn (mut ws Client) manage_clean_close() {
ws.send_close_event(1000, 'closed by client')
}
// ping sends ping message to server
pub fn (mut ws Client) ping() ? {
ws.send_control_frame(.ping, 'PING', []) ?
}
// pong sends pong message to server,
pub fn (mut ws Client) pong() ? {
ws.send_control_frame(.pong, 'PONG', []) ?
}
// write_ptr writes len bytes provided a byteptr with a websocket messagetype
pub fn (mut ws Client) write_ptr(bytes byteptr, payload_len int, code OPCode) ?int {
// ws.debug_log('write_ptr code: $code')
if ws.state != .open || ws.conn.sock.handle < 1 {
// todo: send error here later
return error('trying to write on a closed socket!')
}
mut header_len := 2 + if payload_len > 125 { 2 } else { 0 } +
if payload_len > 0xffff { 6 } else { 0 }
if !ws.is_server {
header_len += 4
}
mut header := []byte{len: header_len, init: `0`} // [`0`].repeat(header_len)
header[0] = byte(int(code)) | 0x80
masking_key := create_masking_key()
if ws.is_server {
if payload_len <= 125 {
header[1] = byte(payload_len)
} else if payload_len > 125 && payload_len <= 0xffff {
len16 := C.htons(payload_len)
header[1] = 126
unsafe { C.memcpy(&header[2], &len16, 2) }
} else if payload_len > 0xffff && payload_len <= 0xffffffffffffffff {
len_bytes := htonl64(u64(payload_len))
header[1] = 127
unsafe { C.memcpy(&header[2], len_bytes.data, 8) }
}
} else {
if payload_len <= 125 {
header[1] = byte(payload_len | 0x80)
header[2] = masking_key[0]
header[3] = masking_key[1]
header[4] = masking_key[2]
header[5] = masking_key[3]
} else if payload_len > 125 && payload_len <= 0xffff {
len16 := C.htons(payload_len)
header[1] = (126 | 0x80)
unsafe { C.memcpy(&header[2], &len16, 2) }
header[4] = masking_key[0]
header[5] = masking_key[1]
header[6] = masking_key[2]
header[7] = masking_key[3]
} else if payload_len > 0xffff && payload_len <= 0xffffffffffffffff {
len64 := htonl64(u64(payload_len))
header[1] = (127 | 0x80)
unsafe { C.memcpy(&header[2], len64.data, 8) }
header[10] = masking_key[0]
header[11] = masking_key[1]
header[12] = masking_key[2]
header[13] = masking_key[3]
} else {
ws.close(1009, 'frame too large') ?
return error('frame too large')
}
}
len := header.len + payload_len
mut frame_buf := []byte{len: len}
unsafe {
C.memcpy(&frame_buf[0], byteptr(header.data), header.len)
if payload_len > 0 {
C.memcpy(&frame_buf[header.len], bytes, payload_len)
}
}
if !ws.is_server {
for i in 0 .. payload_len {
frame_buf[header_len + i] ^= masking_key[i % 4] & 0xff
}
}
written_len := ws.socket_write(frame_buf) ?
unsafe {
frame_buf.free()
masking_key.free()
header.free()
}
return written_len
}
// write writes a byte array with a websocket messagetype to socket
pub fn (mut ws Client) write(bytes []byte, code OPCode) ?int {
return ws.write_ptr(byteptr(bytes.data), bytes.len, code)
}
// write_str, writes a string with a websocket texttype to socket
pub fn (mut ws Client) write_str(str string) ?int {
return ws.write_ptr(str.str, str.len, .text_frame)
}
// close closes the websocket connection
pub fn (mut ws Client) close(code int, message string) ? {
ws.debug_log('sending close, $code, $message')
if ws.state in [.closed, .closing] || ws.conn.sock.handle <= 1 {
ws.debug_log('close: Websocket allready closed ($ws.state), $message, $code handle($ws.conn.sock.handle)')
err_msg := 'Socket allready closed: $code'
return error(err_msg)
}
defer {
ws.shutdown_socket() or { }
ws.reset_state()
}
ws.set_state(.closing)
mut code32 := 0
if code > 0 {
code_ := C.htons(code)
message_len := message.len + 2
mut close_frame := []byte{len: message_len}
close_frame[0] = byte(code_ & 0xFF)
close_frame[1] = byte(code_ >> 8)
code32 = (close_frame[0] << 8) + close_frame[1]
for i in 0 .. message.len {
close_frame[i + 2] = message[i]
}
ws.send_control_frame(.close, 'CLOSE', close_frame) ?
unsafe { close_frame.free() }
} else {
ws.send_control_frame(.close, 'CLOSE', []) ?
}
ws.fragments = []
}
// send_control_frame sends a control frame to the server
fn (mut ws Client) send_control_frame(code OPCode, frame_typ string, payload []byte) ? {
ws.debug_log('send control frame $code, frame_type: $frame_typ')
if ws.state !in [.open, .closing] && ws.conn.sock.handle > 1 {
return error('socket is not connected')
}
header_len := if ws.is_server { 2 } else { 6 }
frame_len := header_len + payload.len
mut control_frame := []byte{len: frame_len}
mut masking_key := if !ws.is_server { create_masking_key() } else { websocket.empty_bytearr }
defer {
unsafe {
control_frame.free()
if masking_key.len > 0 {
masking_key.free()
}
}
}
control_frame[0] = byte(int(code) | 0x80)
if !ws.is_server {
control_frame[1] = byte(payload.len | 0x80)
control_frame[2] = masking_key[0]
control_frame[3] = masking_key[1]
control_frame[4] = masking_key[2]
control_frame[5] = masking_key[3]
} else {
control_frame[1] = byte(payload.len)
}
if code == .close {
if payload.len >= 2 {
if !ws.is_server {
mut parsed_payload := []byte{len: payload.len + 1}
unsafe { C.memcpy(parsed_payload.data, &payload[0], payload.len) }
parsed_payload[payload.len] = `\0`
for i in 0 .. payload.len {
control_frame[6 + i] = (parsed_payload[i] ^ masking_key[i % 4]) & 0xff
}
unsafe { parsed_payload.free() }
} else {
unsafe { C.memcpy(&control_frame[2], &payload[0], payload.len) }
}
}
} else {
if !ws.is_server {
if payload.len > 0 {
for i in 0 .. payload.len {
control_frame[header_len + i] = (payload[i] ^ masking_key[i % 4]) & 0xff
}
}
} else {
if payload.len > 0 {
unsafe { C.memcpy(&control_frame[2], &payload[0], payload.len) }
}
}
}
ws.socket_write(control_frame) or {
return error('send_control_frame: error sending $frame_typ control frame.')
}
}
// parse_uri parses the url to a Uri
fn parse_uri(url string) ?&Uri {
u := urllib.parse(url) ?
request_uri := u.request_uri()
v := request_uri.split('?')
mut port := u.port()
uri := u.str()
if port == '' {
port = if uri.starts_with('ws://') {
'80'
} else if uri.starts_with('wss://') {
'443'
} else {
u.port()
}
}
querystring := if v.len > 1 { '?' + v[1] } else { '' }
return &Uri{
url: url
hostname: u.hostname()
port: port
resource: v[0]
querystring: querystring
}
}
// set_state sets current state of the websocket connection
fn (mut ws Client) set_state(state State) {
lock {
ws.state = state
}
}
// assert_not_connected returns error if the connection is not connected
fn (ws Client) assert_not_connected() ? {
match ws.state {
.connecting { return error('connect: websocket is connecting') }
.open { return error('connect: websocket already open') }
.closing { return error('connect: reconnect on closing websocket not supported, please use new client') }
else {}
}
}
// reset_state resets the websocket and initialize default settings
fn (mut ws Client) reset_state() {
lock {
ws.state = .closed
ws.ssl_conn = openssl.new_ssl_conn()
ws.flags = []
ws.fragments = []
}
}
// debug_log handles debug logging output for client and server
fn (mut ws Client) debug_log(text string) {
if ws.is_server {
ws.logger.debug('server-> $text')
} else {
ws.logger.debug('client-> $text')
}
}
// free handles manual free memory of Message struct
pub fn (m &Message) free() {
unsafe { m.payload.free() }
}
// free handles manual free memory of Client struct
pub fn (c &Client) free() {
unsafe {
c.flags.free()
c.fragments.free()
c.message_callbacks.free()
c.error_callbacks.free()
c.open_callbacks.free()
c.close_callbacks.free()
}
}