/
client.go
188 lines (170 loc) · 3.82 KB
/
client.go
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package ws
import (
"context"
"errors"
"net"
"net/http"
"net/url"
"sync"
"syscall"
"github.com/fasthttp/websocket"
"github.com/go-kit/kit/transport"
kithttp "github.com/go-kit/kit/transport/http"
"golang.org/x/sync/errgroup"
"github.com/einouqo/ext-kit/endpoint"
)
type Client[OUT, IN any] struct {
url url.URL
enc EncodeFunc[OUT]
dec DecodeFunc[IN]
closure Closure
opts clientOptions
}
func NewClient[OUT, IN any](
url url.URL,
enc EncodeFunc[OUT],
dec DecodeFunc[IN],
closure Closure,
opts ...ClientOption,
) *Client[OUT, IN] {
c := &Client[OUT, IN]{
url: url,
enc: enc,
dec: dec,
closure: closure,
}
for _, opt := range opts {
opt.apply(&c.opts)
}
return c
}
func (c *Client[OUT, IN]) Endpoint() endpoint.BiStream[OUT, IN] {
return func(ctx context.Context, receiver <-chan OUT) (rcv endpoint.Receive[IN], err error) {
headers := make(http.Header)
dialer := dialler{websocket.DefaultDialer}
for _, f := range c.opts.before {
ctx = f(ctx, dialer, headers)
}
wsc, resp, err := dialer.DialContext(ctx, c.url.String(), headers)
if err != nil {
return nil, err
}
defer func() {
if err != nil {
_ = wsc.Close()
}
}()
defer resp.Body.Close()
for _, f := range c.opts.after {
ctx = f(ctx, resp, wsc)
}
conn := enhConn{wsc, c.opts.enhancement.config}
once := sync.Once{}
doneCh := make(chan struct{})
group := errgroup.Group{}
group.Go(func() (err error) {
defer close(doneCh)
defer once.Do(func() {
code, msg, deadline := c.closure(ctx, err)
data := websocket.FormatCloseMessage(code.fastsocket(), msg)
_ = conn.WriteControl(websocket.CloseMessage, data, deadline)
})
for {
select {
case <-ctx.Done():
return ctx.Err()
case out, ok := <-receiver:
if !ok {
return nil
}
msg, mt, err := c.enc(ctx, out)
if err != nil {
return err
}
err = conn.WriteMessage(mt.fastsocket(), msg)
switch {
case errors.Is(err, net.ErrClosed):
return nil
case errors.Is(err, syscall.EPIPE): // broken pipe can appear on closed underlying tcp connection by peer
return nil
case errors.Is(err, websocket.ErrCloseSent):
return nil
case err != nil:
return err
}
}
}
})
inCh := make(chan IN)
group.Go(func() (err error) {
if c.opts.finalizer != nil {
defer func() {
for _, f := range c.opts.finalizer {
f(ctx, err)
}
}()
}
defer close(inCh)
defer conn.Close()
defer once.Do(func() {
code, msg, deadline := c.closure(ctx, err)
data := websocket.FormatCloseMessage(code.fastsocket(), msg)
_ = conn.WriteControl(websocket.CloseMessage, data, deadline)
})
for {
messageType, msg, err := conn.ReadMessage()
switch {
case websocket.IsCloseError(err, websocket.CloseNormalClosure):
return nil
case err != nil:
return err
}
mt := MessageType(messageType)
in, err := c.dec(ctx, mt, msg)
if err != nil {
return err
}
inCh <- in
}
})
if c.opts.heartbeat.enable {
group.Go(func() error {
defer conn.Close()
return heartbeat(ctx, c.opts.heartbeat.config, conn, doneCh)
})
}
errCh := make(chan error)
go func() {
defer close(errCh)
err := group.Wait()
if err != nil {
for _, h := range c.opts.errHandlers {
h.Handle(ctx, err)
}
errCh <- err
}
}()
return func() (in IN, err error) {
if in, ok := <-inCh; ok {
return in, nil
}
if err, ok := <-errCh; ok {
return in, err
}
return in, endpoint.StreamDone
}, nil
}
}
type clientOptions struct {
before []DiallerFunc
after []ClientTunerFunc
finalizer []kithttp.ClientFinalizerFunc
errHandlers []transport.ErrorHandler
enhancement struct {
config enhConfig
}
heartbeat struct {
enable bool
config hbConfig
}
}