package rpcclient
|
|
|
|
import (
|
|
"encoding/json"
|
|
"net"
|
|
"net/http"
|
|
"time"
|
|
|
|
"github.com/gorilla/websocket"
|
|
"github.com/pkg/errors"
|
|
types "github.com/tendermint/tendermint/rpc/lib/types"
|
|
cmn "github.com/tendermint/tmlibs/common"
|
|
)
|
|
|
|
const (
|
|
wsResultsChannelCapacity = 10
|
|
wsErrorsChannelCapacity = 1
|
|
wsWriteTimeoutSeconds = 10
|
|
)
|
|
|
|
type WSClient struct {
|
|
cmn.BaseService
|
|
Address string // IP:PORT or /path/to/socket
|
|
Endpoint string // /websocket/url/endpoint
|
|
Dialer func(string, string) (net.Conn, error)
|
|
*websocket.Conn
|
|
ResultsCh chan json.RawMessage // closes upon WSClient.Stop()
|
|
ErrorsCh chan error // closes upon WSClient.Stop()
|
|
}
|
|
|
|
// create a new connection
|
|
func NewWSClient(remoteAddr, endpoint string) *WSClient {
|
|
addr, dialer := makeHTTPDialer(remoteAddr)
|
|
wsClient := &WSClient{
|
|
Address: addr,
|
|
Dialer: dialer,
|
|
Endpoint: endpoint,
|
|
Conn: nil,
|
|
}
|
|
wsClient.BaseService = *cmn.NewBaseService(log, "WSClient", wsClient)
|
|
return wsClient
|
|
}
|
|
|
|
func (wsc *WSClient) String() string {
|
|
return wsc.Address + ", " + wsc.Endpoint
|
|
}
|
|
|
|
// OnStart implements cmn.BaseService interface
|
|
func (wsc *WSClient) OnStart() error {
|
|
wsc.BaseService.OnStart()
|
|
err := wsc.dial()
|
|
if err != nil {
|
|
return err
|
|
}
|
|
wsc.ResultsCh = make(chan json.RawMessage, wsResultsChannelCapacity)
|
|
wsc.ErrorsCh = make(chan error, wsErrorsChannelCapacity)
|
|
go wsc.receiveEventsRoutine()
|
|
return nil
|
|
}
|
|
|
|
// OnReset implements cmn.BaseService interface
|
|
func (wsc *WSClient) OnReset() error {
|
|
return nil
|
|
}
|
|
|
|
func (wsc *WSClient) dial() error {
|
|
|
|
// Dial
|
|
dialer := &websocket.Dialer{
|
|
NetDial: wsc.Dialer,
|
|
Proxy: http.ProxyFromEnvironment,
|
|
}
|
|
rHeader := http.Header{}
|
|
con, _, err := dialer.Dial("ws://"+wsc.Address+wsc.Endpoint, rHeader)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
// Set the ping/pong handlers
|
|
con.SetPingHandler(func(m string) error {
|
|
// NOTE: https://github.com/gorilla/websocket/issues/97
|
|
go con.WriteControl(websocket.PongMessage, []byte(m), time.Now().Add(time.Second*wsWriteTimeoutSeconds))
|
|
return nil
|
|
})
|
|
con.SetPongHandler(func(m string) error {
|
|
// NOTE: https://github.com/gorilla/websocket/issues/97
|
|
return nil
|
|
})
|
|
wsc.Conn = con
|
|
return nil
|
|
}
|
|
|
|
// OnStop implements cmn.BaseService interface
|
|
func (wsc *WSClient) OnStop() {
|
|
wsc.BaseService.OnStop()
|
|
wsc.Conn.Close()
|
|
// ResultsCh/ErrorsCh is closed in receiveEventsRoutine.
|
|
}
|
|
|
|
func (wsc *WSClient) receiveEventsRoutine() {
|
|
for {
|
|
_, data, err := wsc.ReadMessage()
|
|
if err != nil {
|
|
log.Info("WSClient failed to read message", "error", err, "data", string(data))
|
|
wsc.Stop()
|
|
break
|
|
} else {
|
|
var response types.RPCResponse
|
|
err := json.Unmarshal(data, &response)
|
|
if err != nil {
|
|
log.Info("WSClient failed to parse message", "error", err, "data", string(data))
|
|
wsc.ErrorsCh <- err
|
|
continue
|
|
}
|
|
if response.Error != "" {
|
|
wsc.ErrorsCh <- errors.Errorf(response.Error)
|
|
continue
|
|
}
|
|
wsc.ResultsCh <- *response.Result
|
|
}
|
|
}
|
|
// this must be modified in the same go-routine that reads from the
|
|
// connection to avoid race conditions
|
|
wsc.Conn = nil
|
|
|
|
// Cleanup
|
|
close(wsc.ResultsCh)
|
|
close(wsc.ErrorsCh)
|
|
}
|
|
|
|
// Subscribe to an event. Note the server must have a "subscribe" route
|
|
// defined.
|
|
func (wsc *WSClient) Subscribe(eventid string) error {
|
|
params := map[string]interface{}{"event": eventid}
|
|
request, err := types.MapToRequest("", "subscribe", params)
|
|
if err == nil {
|
|
err = wsc.WriteJSON(request)
|
|
}
|
|
return err
|
|
}
|
|
|
|
// Unsubscribe from an event. Note the server must have a "unsubscribe" route
|
|
// defined.
|
|
func (wsc *WSClient) Unsubscribe(eventid string) error {
|
|
params := map[string]interface{}{"event": eventid}
|
|
request, err := types.MapToRequest("", "unsubscribe", params)
|
|
if err == nil {
|
|
err = wsc.WriteJSON(request)
|
|
}
|
|
return err
|
|
}
|
|
|
|
// Call asynchronously calls a given method by sending an RPCRequest to the
|
|
// server. Results will be available on ResultsCh, errors, if any, on ErrorsCh.
|
|
func (wsc *WSClient) Call(method string, params map[string]interface{}) error {
|
|
request, err := types.MapToRequest("", method, params)
|
|
if err == nil {
|
|
err = wsc.WriteJSON(request)
|
|
}
|
|
return err
|
|
}
|