package liveshare
import (
"context"
"fmt"
"io"
"sync"
"time"
"github.com/opentracing/opentracing-go"
"github.com/sourcegraph/jsonrpc2"
)
type rpcClient struct {
*jsonrpc2.Conn
conn io.ReadWriteCloser
handlersMu sync.Mutex
handlers map[string][]*handlerWrapper
}
func newRPCClient(conn io.ReadWriteCloser) *rpcClient {
return &rpcClient{conn: conn, handlers: make(map[string][]*handlerWrapper)}
}
func (r *rpcClient) connect(ctx context.Context) {
stream := jsonrpc2.NewBufferedStream(r.conn, jsonrpc2.VSCodeObjectCodec{})
r.Conn = jsonrpc2.NewConn(ctx, stream, r)
}
func (r *rpcClient) do(ctx context.Context, method string, args, result interface{}) error {
span, ctx := opentracing.StartSpanFromContext(ctx, method)
defer span.Finish()
waiter, err := r.Conn.DispatchCall(ctx, method, args)
if err != nil {
return fmt.Errorf("error dispatching %q call: %w", method, err)
}
// timeout for waiter in case a connection cannot be made
waitCtx, cancel := context.WithTimeout(ctx, 2*time.Minute)
defer cancel()
return waiter.Wait(waitCtx, result)
}
type handler func(conn *jsonrpc2.Conn, req *jsonrpc2.Request)
type handlerWrapper struct {
fn handler
}
func (r *rpcClient) register(requestType string, fn handler) func() {
r.handlersMu.Lock()
defer r.handlersMu.Unlock()
h := &handlerWrapper{fn: fn}
r.handlers[requestType] = append(r.handlers[requestType], h)
return func() {
r.deregister(requestType, h)
}
}
func (r *rpcClient) deregister(requestType string, handler *handlerWrapper) {
r.handlersMu.Lock()
defer r.handlersMu.Unlock()
handlers := r.handlers[requestType]
for i, h := range handlers {
if h == handler {
// Swap h with last element and pop.
last := len(handlers) - 1
handlers[i], handlers[last] = handlers[last], nil
r.handlers[requestType] = handlers[:last]
break
}
}
}
func (r *rpcClient) Handle(ctx context.Context, conn *jsonrpc2.Conn, req *jsonrpc2.Request) {
r.handlersMu.Lock()
defer r.handlersMu.Unlock()
for _, handler := range r.handlers[req.Method] {
go handler.fn(conn, req)
}
}