protected void serviceStreamingRequest()

in core/src/main/java/flex/messaging/endpoints/BaseStreamingHTTPEndpoint.java [930:1030]
67 lines of code
24 McCabe index (conditional complexity)

    protected void serviceStreamingRequest(HttpServletRequest req, HttpServletResponse res) {
        // If this is a request for a streaming connection, make sure it's for a valid FlexClient
        // and that the FlexSession doesn't already have a streaming connection open.
        // Streaming requests are POSTs (to help prevent the possibility of caching) that carry the
        // following parameters:
        // command - Indicating a custom command for the endpoint; currently 'open' to request a new
        //           streaming connection be opened, and 'close' to request the streaming connection
        //           to close.
        // version - Indicates the streaming connection 'version' to use; it's here for backward comp. support
        //           if we need to change how commands are handled in a future product release.
        // DSId - The FlexClient id value that uniquely identifies the swf making the request.
        String command = req.getParameter(COMMAND_PARAM_NAME);

        // Only HTTP 1.1 is supported, disallow HTTP 1.0.
        if (req.getProtocol().equals(HTTP_1_0)) {
            if (Log.isError())
                log.error("Endpoint with id '" + getId() + "' cannot service the streaming request made with " +
                        " HTTP 1.0. Only HTTP 1.1 is supported.");

            try {
                // Return an HTTP status code 400 to indicate that the client's request was syntactically invalid (bad command).
                res.sendError(HttpServletResponse.SC_BAD_REQUEST);
            } catch (IOException ignore) {
            }
            return; // Abort further server processing.
        }

        if (!(command.equals(OPEN_COMMAND) || command.equals(CLOSE_COMMAND))) {
            if (Log.isError())
                log.error("Endpoint with id '" + getId() + "' cannot service the streaming request as the supplied command '"
                        + command + "' is invalid.");

            try {
                // Return an HTTP status code 400 to indicate that the client's request was syntactically invalid (bad command).
                res.sendError(HttpServletResponse.SC_BAD_REQUEST);
            } catch (IOException ignore) {
            }
            return; // Abort further server processing.
        }

        String flexClientId = req.getParameter(Message.FLEX_CLIENT_ID_HEADER);
        if (flexClientId == null) {
            if (Log.isError())
                log.error("Endpoint with id '" + getId() + "' cannot service the streaming request as no FlexClient id"
                        + " has been supplied in the request.");

            try {
                // Return an HTTP status code 400 to indicate that the client's request was syntactically invalid (missing id).
                res.sendError(HttpServletResponse.SC_BAD_REQUEST);
            } catch (IOException ignore) {
            }
            return; // Abort further server processing.
        }

        // Validate that the provided FlexClient id exists and is associated with the current session.
        // We don't do this validation with CLOSE_COMMAND because CLOSE_COMMAND can come in on a
        // different session. For example, when the session expires due to timeout, the streaming client
        // using that session sends a CLOSE_COMMAND on a new session to let the server know to clean client's
        // corresponding server constructs. In that case, server already knows that session has expired so
        // we can simply omit this validation.
        FlexClient flexClient = null;
        List<FlexClient> flexClients = FlexContext.getFlexSession().getFlexClients();
        boolean validFlexClientId = false;
        for (Iterator<FlexClient> iter = flexClients.iterator(); iter.hasNext(); ) {
            flexClient = iter.next();
            if (flexClient.getId().equals(flexClientId) && flexClient.isValid()) {
                validFlexClientId = true;
                break;
            }
        }
        if (!command.equals(CLOSE_COMMAND) && !validFlexClientId) {
            if (Log.isError())
                log.error("Endpoint with id '" + getId() + "' cannot service the streaming request as either the supplied"
                        + " FlexClient id '" + flexClientId + " is not valid, or the FlexClient with that id is not valid.");

            try {
                // Return an HTTP status code 400 to indicate that the client's request was syntactically invalid (invalid id).
                res.sendError(HttpServletResponse.SC_BAD_REQUEST);
            } catch (IOException ignore) {
            }
            return; // Abort further server processing.
        }

        // If a close command is received and we don't have any flex clients registered simply invalidate 
        // the Flex Session. This will take care of the Flex Session that got created when the MB servlet 
        // was processing the CLOSE request.
        if (command.equals(CLOSE_COMMAND) && flexClients.size() == 0) {
            FlexSession flexSession = FlexContext.getFlexSession();
            if (flexSession instanceof HttpFlexSession) {
                ((HttpFlexSession) flexSession).invalidate(false);
            }
            return;
        }

        if (flexClient != null) {
            if (command.equals(OPEN_COMMAND))
                handleFlexClientStreamingOpenRequest(req, res, flexClient);
            else if (command.equals(CLOSE_COMMAND))
                handleFlexClientStreamingCloseRequest(req, res, flexClient, req.getParameter(STREAM_ID_PARAM_NAME));
        }
    }