Examples with StreamingHtmlWriter org.structr.rest.serialization.StreamingHtmlWriter used on opensource projects

Example 1 with StreamingHtmlWriter

use of org.structr.rest.serialization.StreamingHtmlWriter in project structr by structr.

the class JsonRestServlet method doGetOrHead.

private void doGetOrHead(final HttpServletRequest request, final HttpServletResponse response, final boolean returnContent) throws ServletException, IOException {
    SecurityContext securityContext = null;
    Authenticator authenticator = null;
    Result result = null;
    Resource resource = null;
    try {
        // first thing to do!
        request.setCharacterEncoding("UTF-8");
        response.setCharacterEncoding("UTF-8");
        response.setContentType("application/json; charset=utf-8");
        // isolate request authentication in a transaction
        try (final Tx tx = StructrApp.getInstance().tx()) {
            authenticator = config.getAuthenticator();
            securityContext = authenticator.initializeAndExamineRequest(request, response);
            tx.success();
        }
        final App app = StructrApp.getInstance(securityContext);
        // set default value for property view
        propertyView.set(securityContext, config.getDefaultPropertyView());
        // evaluate constraints and measure query time
        double queryTimeStart = System.nanoTime();
        // isolate resource authentication
        try (final Tx tx = app.tx()) {
            resource = ResourceHelper.applyViewTransformation(request, securityContext, ResourceHelper.optimizeNestedResourceChain(securityContext, request, resourceMap, propertyView), propertyView);
            authenticator.checkResourceAccess(securityContext, request, resource.getResourceSignature(), propertyView.get(securityContext));
            tx.success();
        }
        // add sorting & paging
        String pageSizeParameter = request.getParameter(REQUEST_PARAMETER_PAGE_SIZE);
        String pageParameter = request.getParameter(REQUEST_PARAMETER_PAGE_NUMBER);
        String sortOrder = request.getParameter(REQUEST_PARAMETER_SORT_ORDER);
        String sortKeyName = request.getParameter(REQUEST_PARAMETER_SORT_KEY);
        String outputDepth = request.getParameter(REQUEST_PARAMTER_OUTPUT_DEPTH);
        boolean sortDescending = (sortOrder != null && "desc".equals(sortOrder.toLowerCase()));
        int pageSize = Services.parseInt(pageSizeParameter, NodeFactory.DEFAULT_PAGE_SIZE);
        int page = Services.parseInt(pageParameter, NodeFactory.DEFAULT_PAGE);
        int depth = Services.parseInt(outputDepth, config.getOutputNestingDepth());
        String baseUrl = request.getRequestURI();
        PropertyKey sortKey = null;
        // set sort key
        if (sortKeyName != null) {
            Class<? extends GraphObject> type = resource.getEntityClass();
            if (type == null) {
                // fallback to default implementation
                // if no type can be determined
                type = AbstractNode.class;
            }
            sortKey = StructrApp.getConfiguration().getPropertyKeyForDatabaseName(type, sortKeyName, false);
        }
        // isolate doGet
        boolean retry = true;
        while (retry) {
            try (final Tx tx = app.tx()) {
                result = resource.doGet(sortKey, sortDescending, pageSize, page);
                tx.success();
                retry = false;
            } catch (RetryException ddex) {
                retry = true;
            }
        }
        if (result == null) {
            throw new FrameworkException(HttpServletResponse.SC_SERVICE_UNAVAILABLE, "Unable to retrieve result, check database connection");
        }
        if (returnContent) {
            if (!(resource instanceof StaticRelationshipResource) && !result.isPrimitiveArray() && !result.isEmpty()) {
                result.setIsCollection(resource.isCollectionResource());
                result.setIsPrimitiveArray(resource.isPrimitiveArray());
            }
            PagingHelper.addPagingParameter(result, pageSize, page);
            // timing..
            double queryTimeEnd = System.nanoTime();
            // store property view that will be used to render the results
            result.setPropertyView(propertyView.get(securityContext));
            // allow resource to modify result set
            resource.postProcessResultSet(result);
            DecimalFormat decimalFormat = new DecimalFormat("0.000000000", DecimalFormatSymbols.getInstance(Locale.ENGLISH));
            result.setQueryTime(decimalFormat.format((queryTimeEnd - queryTimeStart) / 1000000000.0));
            if (outputDepth != null) {
                result.setOutputNestingDepth(depth);
            }
            String accept = request.getHeader("Accept");
            if (accept != null && accept.contains("text/html")) {
                final StreamingHtmlWriter htmlStreamer = new StreamingHtmlWriter(this.propertyView, indentJson, depth);
                // isolate write output
                try (final Tx tx = app.tx()) {
                    // no trailing semicolon so we dont trip MimeTypes.getContentTypeWithoutCharset
                    response.setContentType("text/html; charset=utf-8");
                    final Writer writer = response.getWriter();
                    htmlStreamer.stream(securityContext, writer, result, baseUrl);
                    // useful newline
                    writer.append("\n");
                    tx.success();
                }
            } else {
                final StreamingJsonWriter jsonStreamer = new StreamingJsonWriter(this.propertyView, indentJson, depth);
                // isolate write output
                try (final Tx tx = app.tx()) {
                    // no trailing semicolon so we dont trip MimeTypes.getContentTypeWithoutCharset
                    response.setContentType("application/json; charset=utf-8");
                    final Writer writer = response.getWriter();
                    jsonStreamer.stream(securityContext, writer, result, baseUrl);
                    // useful newline
                    writer.append("\n");
                    tx.success();
                }
            }
        }
        response.setStatus(HttpServletResponse.SC_OK);
    } catch (FrameworkException frameworkException) {
        // set status & write JSON output
        response.setStatus(frameworkException.getStatus());
        gson.get().toJson(frameworkException, response.getWriter());
        response.getWriter().println();
    } catch (JsonSyntaxException jsex) {
        logger.warn("JsonSyntaxException in GET", jsex);
        int code = HttpServletResponse.SC_BAD_REQUEST;
        response.setStatus(code);
        response.getWriter().append(RestMethodResult.jsonError(code, "Json syntax exception in GET: " + jsex.getMessage()));
    } catch (JsonParseException jpex) {
        logger.warn("JsonParseException in GET", jpex);
        int code = HttpServletResponse.SC_BAD_REQUEST;
        response.setStatus(code);
        response.getWriter().append(RestMethodResult.jsonError(code, "Parser exception in GET: " + jpex.getMessage()));
    } catch (Throwable t) {
        logger.warn("Exception in GET (URI: {})", securityContext != null ? securityContext.getCompoundRequestURI() : "(null SecurityContext)");
        logger.warn(" => Error thrown: ", t);
        int code = HttpServletResponse.SC_INTERNAL_SERVER_ERROR;
        response.setStatus(code);
        response.getWriter().append(RestMethodResult.jsonError(code, "Exception in GET: " + t.getMessage()));
    } finally {
        try {
            // response.getWriter().flush();
            response.getWriter().close();
        } catch (Throwable t) {
            logger.warn("Unable to flush and close response: {}", t.getMessage());
        }
    }
}