Examples with StreamResourceWriter com.vaadin.flow.server.StreamResourceWriter used on opensource projects

Example 1 with StreamResourceWriter

use of com.vaadin.flow.server.StreamResourceWriter in project flow by vaadin.

the class StreamResourceHandlerTest method inputStreamResourceWriterThrows_responseStatusIs500.

@Test
public void inputStreamResourceWriterThrows_responseStatusIs500() throws IOException {
    StreamResource res = new StreamResource("readme.md", (StreamResourceWriter) (stream, session) -> {
        throw new RuntimeException("Simulated");
    });
    try {
        handler.handleRequest(session, request, response, res);
    } catch (RuntimeException ignore) {
    // Ignore exception, it's expected. We need to check the status
    }
    Mockito.verify(response).setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
}

Example 2 with StreamResourceWriter

use of com.vaadin.flow.server.StreamResourceWriter in project flow by vaadin.

the class StreamResourceHandler method handleRequest.

/**
 * Handle sending for a stream resource request.
 *
 * @param session
 *            session for the request
 * @param request
 *            request to handle
 * @param response
 *            response object to which a response can be written.
 * @param streamResource
 *            stream resource that handles data writer
 *
 * @throws IOException
 *             if an IO error occurred
 */
public void handleRequest(VaadinSession session, VaadinRequest request, VaadinResponse response, StreamResource streamResource) throws IOException {
    StreamResourceWriter writer;
    session.lock();
    try {
        ServletContext context = ((VaadinServletRequest) request).getServletContext();
        response.setContentType(streamResource.getContentTypeResolver().apply(streamResource, context));
        response.setCacheTime(streamResource.getCacheTime());
        streamResource.getHeaders().forEach((name, value) -> response.setHeader(name, value));
        writer = streamResource.getWriter();
        if (writer == null) {
            throw new IOException("Stream resource produces null input stream");
        }
    } catch (Exception exception) {
        response.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
        throw exception;
    } finally {
        session.unlock();
    }
    // don't use here "try resource" syntax sugar because in case there is
    // an exception the {@code outputStream} will be closed before "catch"
    // block which sets the status code and this code will not have any
    // effect being called after closing the stream (see #8740).
    OutputStream outputStream = null;
    try {
        outputStream = response.getOutputStream();
        writer.accept(outputStream, session);
    } catch (Exception exception) {
        response.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
        throw exception;
    } finally {
        if (outputStream != null) {
            outputStream.close();
        }
    }
}