Method doFilter

java/org/apache/catalina/ssi/SSIFilter.java:109–185

Captures the response, processes SSI directives if the content type matches, and writes the output.

(ServletRequest request, ServletResponse response, FilterChain chain)

     * Captures the response, processes SSI directives if the content type matches, and writes the output.
     */
    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        // cast once
        HttpServletRequest req = (HttpServletRequest) request;
        HttpServletResponse res = (HttpServletResponse) response;

        // setup to capture output
        ByteArrayServletOutputStream basos = new ByteArrayServletOutputStream();
        ResponseIncludeWrapper responseIncludeWrapper = new ResponseIncludeWrapper(res, basos);

        // process remainder of filter chain
        chain.doFilter(req, responseIncludeWrapper);

        // we can't assume the chain flushed its output
        responseIncludeWrapper.flushOutputStreamOrWriter();
        byte[] bytes = basos.toByteArray();

        // get content type
        String contentType = responseIncludeWrapper.getContentType();

        // is this an allowed type for SSI processing?
        if (contentType != null && contentTypeRegEx.matcher(contentType).matches()) {
            String encoding = res.getCharacterEncoding();

            // set up SSI processing
            SSIExternalResolver ssiExternalResolver = new SSIServletExternalResolver(getServletContext(), req, res,
                    isVirtualWebappRelative, debug, encoding);
            SSIProcessor ssiProcessor = new SSIProcessor(ssiExternalResolver, debug, allowExec);

            // prepare readers/writers
            Reader reader = new InputStreamReader(new ByteArrayInputStream(bytes), encoding);
            ByteArrayOutputStream ssiout = new ByteArrayOutputStream();
            PrintWriter writer = new PrintWriter(new OutputStreamWriter(ssiout, encoding));

            // do SSI processing
            long lastModified = ssiProcessor.process(reader, responseIncludeWrapper.getLastModified(), writer);

            // set output bytes
            writer.flush();
            bytes = ssiout.toByteArray();

            // override headers
            if (expires != null) {
                res.setDateHeader("expires", (new java.util.Date()).getTime() + expires.longValue() * 1000);
            }
            if (lastModified > 0) {
                res.setDateHeader("last-modified", lastModified);
            }
            res.setContentLength(bytes.length);

            Matcher shtmlMatcher = shtmlRegEx.matcher(responseIncludeWrapper.getContentType());
            if (shtmlMatcher.matches()) {
                // Convert SHTML mime type to ordinary HTML mime type but preserve
                // encoding, if any.
                String enc = shtmlMatcher.group(1);
                res.setContentType("text/html" + ((enc != null) ? enc : ""));
            }