/**
* Copyright (C) 2012-2017 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ninja.diagnostics;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.io.Writer;
import java.net.URI;
import java.net.URL;
import java.util.List;
import java.util.Map;
import ninja.Context;
import ninja.Cookie;
import ninja.Result;
import ninja.Route;
import ninja.exceptions.InternalServerErrorException;
import ninja.utils.ResponseStreams;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringEscapeUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Utility class for rendering <code>DiagnosticError</code> instances as
* a Result. Does not rely on any 3rd party rendering library to permit
* rendering exceptions in the case where a template engine fails!
*
* @author Joe Lauer (https://twitter.com/jjlauer)
* @author Fizzed, Inc. (http://fizzed.com)
*/
public class DiagnosticErrorRenderer {
private static final Logger logger = LoggerFactory.getLogger(DiagnosticErrorRenderer.class);
private final StringBuilder s;
private DiagnosticErrorRenderer() {
s = new StringBuilder();
}
public String render() {
return s.toString();
}
static public void tryToRender(Context context, Result result, DiagnosticError diagnosticError, boolean throwInternalServerExceptionOnError) {
try {
DiagnosticErrorRenderer errorRenderer
= build(context, result, diagnosticError);
errorRenderer.renderResult(
context,
result);
} catch (IOException e) {
// fallback to ninja system-wide error handler?
if (throwInternalServerExceptionOnError) {
throw new InternalServerErrorException(e);
} else {
logger.error("Something is really fishy. Unable to render diagnostic error", e);
}
}
}
public void renderResult(Context context, Result result) throws IOException {
String out = render();
// set context response content type
result.contentType("text/html");
result.charset("utf-8");
ResponseStreams responseStreams = context.finalizeHeaders(result);
try (Writer w = responseStreams.getWriter()) {
w.write(out);
w.flush();
w.close();
}
}
static public DiagnosticErrorRenderer build(Context context,
Result result,
DiagnosticError diagnosticError) throws IOException {
Result underlyingResult = diagnosticError.getUnderlyingResult();
return new DiagnosticErrorRenderer()
.appendHeader(
context,
result,
diagnosticError.getTitle())
.appendTabsBegin(new String[] { "Exception", "Context", "Request", "Response" })
.appendTabBegin(0)
.appendSourceSnippet(
diagnosticError.getSourceLocation(),
diagnosticError.getSourceLines(),
diagnosticError.getLineNumberOfSourceLines(),
diagnosticError.getLineNumberOfError())
.appendThrowable(
diagnosticError.getThrowable())
.appendTabEnd()
.appendTabBegin(1)
.appendContext(context)
.appendTabEnd()
.appendTabBegin(2)
.appendRequest(context)
.appendTabEnd()
.appendTabBegin(3)
.appendResponse(underlyingResult)
.appendTabEnd()
.appendTabsEnd()
.appendFooter();
}
private DiagnosticErrorRenderer appendHeader(Context context,
Result result,
String title) throws IOException {
String headerTemplate = getResource("diagnostic_header.html");
String styleTemplate = getResource("diagnostic.css");
// simple token replacement
headerTemplate = headerTemplate.replace("${TITLE}", escape(title));
headerTemplate = headerTemplate.replace("${STYLE}", escape(styleTemplate));
s.append(headerTemplate);
if (result != null) {
s.append(" <p id=\"detail\">\n");
if (result.getStatusCode() != 200) {
s.append ("Status code ").append(result.getStatusCode());
}
s.append(" for request '").append(context.getMethod()).append(" ").append(context.getRequestPath()).append("'\n");
// append info about the route itself
if (context.getRoute() != null) {
Route route = context.getRoute();
s.append("<br />In controller method '").append(route.getControllerClass().getCanonicalName()).append(".").append(route.getControllerMethod().getName()).append("'\n");
}
s.append(" </p>\n");
}
return this;
}
private DiagnosticErrorRenderer appendTabsBegin(String[] names) throws IOException {
s.append("<div class='tabs standard'>\n");
s.append(" <ul class=\"tab-links\">\n");
for (int i = 0; i < names.length; i++) {
s.append(" <li");
if (i == 0) {
s.append(" class=\"active\"");
}
s.append("><a href=\"#tab").append(i).append("\">").append(escape(names[i])).append("</a></li>\n");
}
s.append(" </ul>\n");
s.append(" <div class=\"tab-content\">\n");
return this;
}
private DiagnosticErrorRenderer appendTabsEnd() throws IOException {
s.append(" </div>\n");
s.append("</div>\n");
return this;
}
private DiagnosticErrorRenderer appendTabBegin(int index) throws IOException {
s.append(" <div id=\"tab").append(index).append("\" class=\"tab");
if (index == 0) {
s.append(" active");
}
s.append("\">\n");
return this;
}
private DiagnosticErrorRenderer appendTabEnd() throws IOException {
s.append(" </div>\n");
return this;
}
private DiagnosticErrorRenderer appendFooter() throws IOException {
// embed jquery
s.append("<script type='text/javascript'>").append(getResource("jquery-1.11.1.min.js")).append("</script>");
// diagnostic javascript
s.append("<script type='text/javascript'>").append(getResource("diagnostic.js")).append("</script>");
// footer body -> html tags
s.append(getResource("diagnostic_footer.html"));
return this;
}
private DiagnosticErrorRenderer appendContext(Context context) throws IOException {
s.append("<div class=\"context\">\n");
s.append("<h2>Route</h2>\n");
if (context.getRoute() != null) {
Route route = context.getRoute();
appendNameValue(s, "Http method", route.getHttpMethod());
appendNameValue(s, "Controller method", route.getControllerClass().getCanonicalName() + "." + route.getControllerMethod().getName() + "()");
StringBuilder params = new StringBuilder();
for (Class type : route.getControllerMethod().getParameterTypes()) {
if (params.length() > 0) { params.append(", "); }
params.append(type.getCanonicalName());
}
appendNameValue(s, "Controller parameters", params.toString());
} else {
appendNoValues(s);
}
s.append("<h2>Session</h2>\n");
if (context.getSession() != null && !context.getSession().getData().isEmpty()) {
for (Map.Entry<String, String> sessionEntry : context.getSession().getData().entrySet()) {
appendNameValue(s, sessionEntry.getKey(), sessionEntry.getValue());
}
} else {
appendNoValues(s);
}
s.append("<h2>Flash</h2>\n");
if (context.getFlashScope() != null && !context.getFlashScope().getCurrentFlashCookieData().isEmpty()) {
for (Map.Entry<String, String> sessionEntry : context.getFlashScope().getCurrentFlashCookieData().entrySet()) {
appendNameValue(s, sessionEntry.getKey(), sessionEntry.getValue());
}
} else {
appendNoValues(s);
}
s.append("<h2>Attributes</h2>\n");
Map<String,Object> attributes = context.getAttributes();
if (attributes != null && !attributes.isEmpty()) {
for (Map.Entry<String,Object> entry : attributes.entrySet()) {
appendNameValue(s, entry.getKey(), (entry.getValue() != null ? entry.getValue().toString() : "null"));
}
} else {
appendNoValues(s);
}
List<Cookie> cookies = context.getCookies();
if (cookies == null || cookies.isEmpty()) {
s.append("<h2>Cookies</h2>\n");
appendNoValues(s);
} else {
for (Cookie cookie : context.getCookies()) {
s.append("<h2>Cookie: ").append(cookie.getName()).append("</h2>\n");
appendNameValue(s, "Value", cookie.getValue());
appendNameValue(s, "Path", cookie.getPath());
appendNameValue(s, "Domain", cookie.getDomain());
appendNameValue(s, "HTTP only", cookie.isHttpOnly()+"");
appendNameValue(s, "Secure", cookie.isSecure()+"");
appendNameValue(s, "Max age", cookie.getMaxAge()+"");
appendNameValue(s, "Comment", cookie.getComment());
}
}
s.append("</div>\n");
return this;
}
private DiagnosticErrorRenderer appendRequest(Context context) throws IOException {
s.append("<div class=\"context\">\n");
s.append("<h2>Request</h2>\n");
appendNameValue(s, "Context path", context.getContextPath());
appendNameValue(s, "Hostname", context.getHostname());
appendNameValue(s, "Method", context.getMethod());
appendNameValue(s, "Remote address", context.getRemoteAddr());
appendNameValue(s, "Content type", context.getRequestContentType());
appendNameValue(s, "Path", context.getRequestPath());
appendNameValue(s, "Scheme", context.getScheme());
s.append("<h2>Parameters</h2>\n");
Map<String, String[]> parameters = context.getParameters();
if (parameters != null && !parameters.isEmpty()) {
for (Map.Entry<String, String[]> entry : parameters.entrySet()) {
for (String value : entry.getValue()) {
appendNameValue(s, entry.getKey(), value);
}
}
} else {
appendNoValues(s);
}
s.append("<h2>Headers</h2>\n");
Map<String, List<String>> headers = context.getHeaders();
if (headers != null && !headers.isEmpty()) {
for (Map.Entry<String, List<String>> entry : headers.entrySet()) {
for (String value : entry.getValue()) {
appendNameValue(s, entry.getKey(), value);
}
}
} else {
appendNoValues(s);
}
s.append("</div>\n");
return this;
}
private DiagnosticErrorRenderer appendResponse(Result result) throws IOException {
s.append("<div class=\"context\">\n");
s.append("<h2>Application Result</h2>\n");
if (result == null) {
// request did not get far enough along in processing to actually
// have a response for us to debug
appendNoValues(s, "Application failure before a result was created");
return this;
}
appendNameValue(s, "Template", result.getTemplate());
appendNameValue(s, "Charset", result.getCharset());
appendNameValue(s, "Content type", result.getContentType());
appendNameValue(s, "Status code", result.getStatusCode()+"");
List<String> supportedContentTypes = result.supportedContentTypes();
if (supportedContentTypes == null || supportedContentTypes.isEmpty()) {
appendNameValue(s, "Supported content types", "None set");
} else {
for (int i = 0; i < supportedContentTypes.size(); i++) {
appendNameValue(s, "Supported content type #" + i, supportedContentTypes.get(i));
}
}
appendNameValue(s, "Fallback content type", result.fallbackContentType().orElse("None set"));
appendNameValue(s, "Json View", (result.getJsonView() != null ? result.getJsonView().getClass().getCanonicalName() : "None"));
s.append("<h2>Renderable</h2>\n");
Object renderable = result.getRenderable();
// only rendering exceptions would have the renderable actually set
// to something other than a DiagnosticError
if (renderable == null || renderable instanceof DiagnosticError) {
appendNoValues(s);
} else if (renderable instanceof Map) {
Map<String,Object> map = (Map<String,Object>)renderable;
for (Map.Entry<String,Object> entry : map.entrySet()) {
appendNameValue(s, entry.getKey(), (entry.getValue() != null ? entry.getValue().toString() : "null"));
}
} else {
appendNameValue(s, "Class of", renderable.getClass().getCanonicalName());
}
s.append("<h2>Headers</h2>\n");
Map<String, String> headers = result.getHeaders();
if (headers != null && !headers.isEmpty()) {
for (Map.Entry<String, String> entry : headers.entrySet()) {
appendNameValue(s, entry.getKey(), entry.getValue());
}
} else {
appendNoValues(s);
}
s.append("</div>\n");
return this;
}
private void appendNameValue(StringBuilder sb, String name, String value) throws IOException {
sb.append("<pre><span class=\"line\" style=\"width: 200px;\">");
sb.append(escape(name));
sb.append("</span><span class=\"route\" style=\"left: 210px\">");
sb.append(escape(value));
sb.append("</span></pre>");
}
private void appendNoValues(StringBuilder sb) throws IOException {
appendNoValues(sb, "No values");
}
private void appendNoValues(StringBuilder sb, String title) throws IOException {
sb.append("<pre style=\"border-bottom: 0px;\"><span style=\"position: absolute; left: 45px;\">").append(escape(title)).append("</span></pre><br/>");
}
private DiagnosticErrorRenderer appendSourceSnippet(URI sourceLocation,
List<String> sourceLines,
int lineNumberOfSourceLines,
int lineNumberOfError) {
if (sourceLocation != null) {
s.append(" <h2>").append(escape(sourceLocation.toString())).append("</h2>\n");
}
if (sourceLines != null) {
s.append(" <div>\n");
for (int i = 0; i < sourceLines.size(); i++) {
s.append("<pre>");
int lineNumber = lineNumberOfSourceLines + i;
// line of error?
String cssClass = (lineNumber == lineNumberOfError ? "line error" : "line info");
s.append("<span class=\"").append(cssClass).append("\">").append(lineNumber).append("</span>");
s.append("<span class=\"")
.append("route")
.append("\">")
.append(escape(sourceLines.get(i)))
.append("</span>");
s.append("</pre>");
}
s.append(" </div>\n");
}
return this;
}
private DiagnosticErrorRenderer appendThrowable(Throwable throwable) throws IOException {
s.append("<h2>Stack Trace</h2>");
if (throwable != null) {
s.append("<pre><span class=\"stacktrace\">").append(escape(throwableStackTraceToString(throwable))).append("</span></pre>\n");
} else {
appendNoValues(s, "Result was not triggered by an exception");
}
return this;
}
private String throwableStackTraceToString(Throwable throwable) {
StringWriter sw = new StringWriter();
try (PrintWriter pw = new PrintWriter(sw)) {
throwable.printStackTrace(pw);
}
return sw.toString();
}
private String escape(String value) {
return StringEscapeUtils.escapeHtml4(value);
}
private String getResource(String resourceName) throws IOException {
URL url = getClass().getResource(resourceName);
if (url == null) {
throw new IOException("Unable to find diagnostic resource: " + resourceName);
}
return IOUtils.toString(url);
}
}