zrpc timeout & unit tests (#573)

* zrpc timeout & unit tests

zrpc/internal/serverinterceptors/timeoutinterceptor.go

@@ -2,6 +2,7 @@ package serverinterceptors
 
 import (
 	"context"
+	"sync"
 	"time"
 
 	"github.com/tal-tech/go-zero/core/contextx"
@@ -11,9 +12,37 @@ import (
 // UnaryTimeoutInterceptor returns a func that sets timeout to incoming unary requests.
 func UnaryTimeoutInterceptor(timeout time.Duration) grpc.UnaryServerInterceptor {
 	return func(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo,
-		handler grpc.UnaryHandler) (resp interface{}, err error) {
+		handler grpc.UnaryHandler) (interface{}, error) {
 		ctx, cancel := contextx.ShrinkDeadline(ctx, timeout)
 		defer cancel()
-		return handler(ctx, req)
+
+		var resp interface{}
+		var err error
+		var lock sync.Mutex
+		done := make(chan struct{})
+		panicChan := make(chan interface{}, 1)
+		go func() {
+			defer func() {
+				if p := recover(); p != nil {
+					panicChan <- p
+				}
+			}()
+
+			lock.Lock()
+			defer lock.Unlock()
+			resp, err = handler(ctx, req)
+			close(done)
+		}()
+
+		select {
+		case p := <-panicChan:
+			panic(p)
+		case <-done:
+			lock.Lock()
+			defer lock.Unlock()
+			return resp, err
+		case <-ctx.Done():
+			return nil, ctx.Err()
+		}
 	}
 }