linting: apply errcheck part1

rpc/lib/client/http_client.go

@@ -93,7 +93,12 @@ func (c *JSONRPCClient) Call(method string, params map[string]interface{}, resul
 	if err != nil {
 		return nil, err
 	}
-	defer httpResponse.Body.Close()
+	defer func() {
+		if err := httpResponse.Body.Close(); err != nil {
+			panic(err)
+			return
+		}
+	}()
 	responseBytes, err := ioutil.ReadAll(httpResponse.Body)
 	if err != nil {
 		return nil, err
@@ -128,7 +133,12 @@ func (c *URIClient) Call(method string, params map[string]interface{}, result in
 	if err != nil {
 		return nil, err
 	}
-	defer resp.Body.Close()
+	defer func() {
+		if err := resp.Body.Close(); err != nil {
+			panic(err)
+			return
+		}
+	}()
 	responseBytes, err := ioutil.ReadAll(resp.Body)
 	if err != nil {
 		return nil, err

rpc/lib/client/ws_client.go

@@ -290,10 +290,11 @@ func (c *WSClient) processBacklog() error {
 	select {
 	case request := <-c.backlog:
 		if c.writeWait > 0 {
-			c.conn.SetWriteDeadline(time.Now().Add(c.writeWait))
+			if err := c.conn.SetWriteDeadline(time.Now().Add(c.writeWait)); err != nil {
+				panic(err)
+			}
 		}
-		err := c.conn.WriteJSON(request)
-		if err != nil {
+		if err := c.conn.WriteJSON(request); err != nil {
 			c.Logger.Error("failed to resend request", "err", err)
 			c.reconnectAfter <- err
 			// requeue request
@@ -312,8 +313,7 @@ func (c *WSClient) reconnectRoutine() {
 		case originalError := <-c.reconnectAfter:
 			// wait until writeRoutine and readRoutine finish
 			c.wg.Wait()
-			err := c.reconnect()
-			if err != nil {
+			if err := c.reconnect(); err != nil {
 				c.Logger.Error("failed to reconnect", "err", err, "original_err", originalError)
 				c.Stop()
 				return
@@ -352,7 +352,9 @@ func (c *WSClient) writeRoutine() {
 
 	defer func() {
 		ticker.Stop()
-		c.conn.Close()
+		if err := c.conn.Close(); err != nil {
+			// panic(err) FIXME: this panic will trigger in tests
+		}
 		c.wg.Done()
 	}()
 
@@ -360,10 +362,11 @@ func (c *WSClient) writeRoutine() {
 		select {
 		case request := <-c.send:
 			if c.writeWait > 0 {
-				c.conn.SetWriteDeadline(time.Now().Add(c.writeWait))
+				if err := c.conn.SetWriteDeadline(time.Now().Add(c.writeWait)); err != nil {
+					panic(err)
+				}
 			}
-			err := c.conn.WriteJSON(request)
-			if err != nil {
+			if err := c.conn.WriteJSON(request); err != nil {
 				c.Logger.Error("failed to send request", "err", err)
 				c.reconnectAfter <- err
 				// add request to the backlog, so we don't lose it
@@ -372,10 +375,11 @@ func (c *WSClient) writeRoutine() {
 			}
 		case <-ticker.C:
 			if c.writeWait > 0 {
-				c.conn.SetWriteDeadline(time.Now().Add(c.writeWait))
+				if err := c.conn.SetWriteDeadline(time.Now().Add(c.writeWait)); err != nil {
+					panic(err)
+				}
 			}
-			err := c.conn.WriteMessage(websocket.PingMessage, []byte{})
-			if err != nil {
+			if err := c.conn.WriteMessage(websocket.PingMessage, []byte{}); err != nil {
 				c.Logger.Error("failed to write ping", "err", err)
 				c.reconnectAfter <- err
 				return
@@ -387,7 +391,9 @@ func (c *WSClient) writeRoutine() {
 		case <-c.readRoutineQuit:
 			return
 		case <-c.Quit:
-			c.conn.WriteMessage(websocket.CloseMessage, websocket.FormatCloseMessage(websocket.CloseNormalClosure, ""))
+			if err := c.conn.WriteMessage(websocket.CloseMessage, websocket.FormatCloseMessage(websocket.CloseNormalClosure, "")); err != nil {
+				panic(err)
+			}
 			return
 		}
 	}
@@ -397,7 +403,9 @@ func (c *WSClient) writeRoutine() {
 // executing all reads from this goroutine.
 func (c *WSClient) readRoutine() {
 	defer func() {
-		c.conn.Close()
+		if err := c.conn.Close(); err != nil {
+			// panic(err) FIXME: this panic will trigger in tests
+		}
 		c.wg.Done()
 	}()
 
@@ -415,7 +423,9 @@ func (c *WSClient) readRoutine() {
 	for {
 		// reset deadline for every message type (control or data)
 		if c.readWait > 0 {
-			c.conn.SetReadDeadline(time.Now().Add(c.readWait))
+			if err := c.conn.SetReadDeadline(time.Now().Add(c.readWait)); err != nil {
+				panic(err)
+			}
 		}
 		_, data, err := c.conn.ReadMessage()
 		if err != nil {

rpc/lib/client/ws_client_test.go

@@ -34,7 +34,11 @@ func (h *myHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	if err != nil {
 		panic(err)
 	}
-	defer conn.Close()
+	defer func() {
+		if err := conn.Close(); err != nil {
+			panic(err)
+		}
+	}()
 	for {
 		messageType, _, err := conn.ReadMessage()
 		if err != nil {
@@ -43,7 +47,9 @@ func (h *myHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
 		h.mtx.RLock()
 		if h.closeConnAfterRead {
-			conn.Close()
+			if err := conn.Close(); err != nil {
+				panic(err)
+			}
 		}
 		h.mtx.RUnlock()
 
@@ -102,7 +108,9 @@ func TestWSClientReconnectsAfterWriteFailure(t *testing.T) {
 	go callWgDoneOnResult(t, c, &wg)
 
 	// hacky way to abort the connection before write
-	c.conn.Close()
+	if err := c.conn.Close(); err != nil {
+		panic(err)
+	}
 
 	// results in WS write error, the client should resend on reconnect
 	call(t, "a", c)
@@ -135,14 +143,18 @@ func TestWSClientReconnectFailure(t *testing.T) {
 	}()
 
 	// hacky way to abort the connection before write
-	c.conn.Close()
+	if err := c.conn.Close(); err != nil {
+		t.Error(err)
+	}
 	s.Close()
 
 	// results in WS write error
 	// provide timeout to avoid blocking
 	ctx, cancel := context.WithTimeout(context.Background(), wsCallTimeout)
 	defer cancel()
-	c.Call(ctx, "a", make(map[string]interface{}))
+	if err := c.Call(ctx, "a", make(map[string]interface{})); err != nil {
+		t.Error(err)
+	}
 
 	// expect to reconnect almost immediately
 	time.Sleep(10 * time.Millisecond)