Examples with ChartProvider org.eclipse.smarthome.ui.chart.ChartProvider used on opensource projects

Example 1 with ChartProvider

use of org.eclipse.smarthome.ui.chart.ChartProvider in project smarthome by eclipse.

the class ChartServlet method doGet.

@Override
protected void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
    logger.debug("Received incoming chart request: {}", req);
    int width = defaultWidth;
    try {
        width = Integer.parseInt(req.getParameter("w"));
    } catch (Exception e) {
    }
    int height = defaultHeight;
    try {
        String h = req.getParameter("h");
        if (h != null) {
            Double d = Double.parseDouble(h) * scale;
            height = d.intValue();
        }
    } catch (Exception e) {
    }
    // To avoid ambiguity you are not allowed to specify period, begin and end time at the same time.
    if (req.getParameter("period") != null && req.getParameter("begin") != null && req.getParameter("end") != null) {
        throw new ServletException("Do not specify the three parameters period, begin and end at the same time.");
    }
    // Read out the parameter period, begin and end and save them.
    Date timeBegin = null;
    Date timeEnd = null;
    Long period = PERIODS.get(req.getParameter("period"));
    if (period == null) {
        // use a day as the default period
        period = PERIODS.get("D");
    }
    if (req.getParameter("begin") != null) {
        try {
            timeBegin = new SimpleDateFormat(DATE_FORMAT).parse(req.getParameter("begin"));
        } catch (ParseException e) {
            throw new ServletException("Begin and end must have this format: " + DATE_FORMAT + ".");
        }
    }
    if (req.getParameter("end") != null) {
        try {
            timeEnd = new SimpleDateFormat(DATE_FORMAT).parse(req.getParameter("end"));
        } catch (ParseException e) {
            throw new ServletException("Begin and end must have this format: " + DATE_FORMAT + ".");
        }
    }
    // Set begin and end time and check legality.
    if (timeBegin == null && timeEnd == null) {
        timeEnd = new Date();
        timeBegin = new Date(timeEnd.getTime() - period);
        logger.debug("No begin or end is specified, use now as end and now-period as begin.");
    } else if (timeEnd == null) {
        timeEnd = new Date(timeBegin.getTime() + period);
        logger.debug("No end is specified, use begin + period as end.");
    } else if (timeBegin == null) {
        timeBegin = new Date(timeEnd.getTime() - period);
        logger.debug("No begin is specified, use end-period as begin");
    } else if (timeEnd.before(timeBegin)) {
        throw new ServletException("The end is before the begin.");
    }
    // If a persistence service is specified, find the provider
    String serviceName = req.getParameter("service");
    ChartProvider provider = getChartProviders().get(providerName);
    if (provider == null) {
        throw new ServletException("Could not get chart provider.");
    }
    // Read out the parameter 'dpi'
    Integer dpi = null;
    if (req.getParameter("dpi") != null) {
        try {
            dpi = Integer.valueOf(req.getParameter("dpi"));
        } catch (NumberFormatException e) {
            throw new ServletException("dpi parameter is invalid");
        }
        if (dpi <= 0) {
            throw new ServletException("dpi parameter is <= 0");
        }
    }
    // Read out parameter 'legend'
    Boolean legend = null;
    if (req.getParameter("legend") != null) {
        legend = BooleanUtils.toBoolean(req.getParameter("legend"));
    }
    if (maxWidth > 0 && width > maxWidth) {
        height = Math.round((float) height / (float) width * maxWidth);
        if (dpi != null) {
            dpi = Math.round((float) dpi / (float) width * maxWidth);
        }
        width = maxWidth;
    }
    // Set the content type to that provided by the chart provider
    res.setContentType("image/" + provider.getChartType());
    logger.debug("chart building with width {} height {} dpi {}", width, height, dpi);
    try (ImageOutputStream imageOutputStream = ImageIO.createImageOutputStream(res.getOutputStream())) {
        BufferedImage chart = provider.createChart(serviceName, req.getParameter("theme"), timeBegin, timeEnd, height, width, req.getParameter("items"), req.getParameter("groups"), dpi, legend);
        ImageIO.write(chart, provider.getChartType().toString(), imageOutputStream);
        logger.debug("Chart successfully generated and written to the response.");
    } catch (ItemNotFoundException e) {
        logger.debug("{}", e.getMessage());
        res.sendError(HttpServletResponse.SC_BAD_REQUEST, e.getMessage());
    } catch (IllegalArgumentException e) {
        logger.warn("Illegal argument in chart: {}", e.getMessage());
        res.sendError(HttpServletResponse.SC_BAD_REQUEST, "Illegal argument in chart: " + e.getMessage());
    } catch (RuntimeException e) {
        if (logger.isDebugEnabled()) {
            // we also attach the stack trace
            logger.warn("Chart generation failed: {}", e.getMessage(), e);
        } else {
            logger.warn("Chart generation failed: {}", e.getMessage());
        }
        res.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR, e.getMessage());
    }
}