DefaultHtmlErrorResponseBodyProvider.java
/*
* Copyright 2017-2024 original 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
*
* https://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 io.micronaut.http.server.exceptions.response;
import io.micronaut.context.MessageSource;
import io.micronaut.context.annotation.Requires;
import io.micronaut.core.annotation.Internal;
import io.micronaut.core.annotation.NonNull;
import io.micronaut.core.util.LocaleResolver;
import io.micronaut.core.util.StringUtils;
import io.micronaut.http.HttpRequest;
import io.micronaut.http.HttpResponse;
import io.micronaut.http.HttpStatus;
import io.micronaut.http.util.HtmlSanitizer;
import jakarta.inject.Singleton;
import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import static io.micronaut.http.HttpStatus.*;
/**
* It generates HTML error response page for a given {@link HttpStatus}.
* @author Sergio del Amo
* @since 4.7.0
*/
@Internal
@Singleton
@Requires(missingBeans = HtmlErrorResponseBodyProvider.class)
final class DefaultHtmlErrorResponseBodyProvider implements HtmlErrorResponseBodyProvider {
private static final Map<Integer, String> DEFAULT_ERROR_BOLD = Map.of(
NOT_FOUND.getCode(), "The page you were looking for doesn���t exist",
REQUEST_ENTITY_TOO_LARGE.getCode(), "The file or data you are trying to upload exceeds the allowed size"
);
private static final Map<Integer, String> DEFAULT_ERROR = Map.of(
NOT_FOUND.getCode(), "You may have mistyped the address or the page may have moved",
REQUEST_ENTITY_TOO_LARGE.getCode(), "Please try again with a smaller file"
);
private static final String CSS = """
*, *::before, *::after {
box-sizing: border-box;
}
* {
margin: 0;
}
html {
font-size: 16px;
}
h2 {
margin-top: -0.95em;
font-size: 6em;
opacity: .2;
}
body {
background: #2559a7;
color: #FFF;
display: grid;
font-family: -apple-system, "Helvetica Neue", Helvetica, sans-serif;
font-size: clamp(1rem, 2.5vw, 2rem);
-webkit-font-smoothing: antialiased;
font-style: normal;
font-weight: 400;
letter-spacing: -0.0025em;
line-height: 1.4;
min-height: 100vh;
place-items: center;
text-rendering: optimizeLegibility;
-webkit-text-size-adjust: 100%;
}
a {
color: inherit;
font-weight: 700;
text-decoration: underline;
text-underline-offset: 0.0925em;
}
b, strong {
font-weight: 700;
}
i, em {
font-style: italic;
}
main {
display: grid;
gap: 1em;
padding: 2em;
place-items: center;
text-align: center;
}
main header {
width: min(100%, 18em);
}
main header svg {
height: auto;
max-width: 100%;
width: 100%;
}
main article {
margin-top: -0.95em;
width: min(100%, 30em);
}
main article p {
font-size: 75%;
}
main article br {
display: none;
@media(min-width: 48em) {
display: inline;
}
}
""";
private final HtmlSanitizer htmlSanitizer;
private final MessageSource messageSource;
private final LocaleResolver<HttpRequest<?>> localeResolver;
private final Map<HtmlErrorPage, String> cache = new ConcurrentHashMap<>();
DefaultHtmlErrorResponseBodyProvider(HtmlSanitizer htmlSanitizer,
MessageSource messageSource,
LocaleResolver<HttpRequest<?>> localeResolver) {
this.htmlSanitizer = htmlSanitizer;
this.messageSource = messageSource;
this.localeResolver = localeResolver;
}
@Override
public String body(@NonNull ErrorContext errorContext, @NonNull HttpResponse<?> response) {
HtmlErrorPage key = error(errorContext, response);
return cache.computeIfAbsent(key, this::html);
}
private String html(@NonNull HtmlErrorPage htmlErrorPage) {
final String errorTitleCode = htmlErrorPage.httpStatusCode() + ".error.title";
final String errorTitle = messageSource.getMessage(errorTitleCode, htmlErrorPage.httpStatusReason(), htmlErrorPage.locale());
String header = "<h1>" + errorTitle + "</h1>";
header += "<h2>" + htmlErrorPage.httpStatusCode() + "</h1>";
return MessageFormat.format("<!doctype html><html lang=\"en\"><head><title>{0} ��� {1}</title><meta charset=\"utf-8\"><meta name=\"viewport\" content=\"initial-scale=1, width=device-width\"><meta name=\"robots\" content=\"noindex, nofollow\"><style>{2}</style></head><body><main><header>{3}</header><article>{4}</article></main></body></html>",
htmlErrorPage.httpStatusCode(),
errorTitle,
CSS,
header,
article(htmlErrorPage));
}
private HtmlErrorPage error(@NonNull ErrorContext errorContext,
@NonNull HttpResponse<?> response) {
int httpStatusCode = response.code();
Locale locale = localeResolver.resolveOrDefault(errorContext.getRequest());
final String errorBoldCode = httpStatusCode + ".error.bold";
final String errorCode = httpStatusCode + ".error";
String defaultErrorBold = DEFAULT_ERROR_BOLD.get(httpStatusCode);
String defaultError = DEFAULT_ERROR.get(httpStatusCode);
String errorBold = defaultErrorBold != null
? messageSource.getMessage(errorBoldCode, defaultErrorBold, locale)
: messageSource.getMessage(errorBoldCode, locale).orElse(null);
String error = defaultError != null
? messageSource.getMessage(errorCode, defaultError, locale)
: messageSource.getMessage(errorCode, locale).orElse(null);
String httpStatusReason = htmlSanitizer.sanitize(response.reason());
List<String> messages = new ArrayList<>();
for (io.micronaut.http.server.exceptions.response.Error e : errorContext.getErrors()) {
if (StringUtils.isNotEmpty(e.getMessage()) && !e.getMessage().equalsIgnoreCase(httpStatusReason)) {
messages.add(htmlSanitizer.sanitize(e.getMessage()));
}
}
return new HtmlErrorPage(locale, httpStatusCode, httpStatusReason, error, errorBold, messages);
}
private String article(@NonNull HtmlErrorPage htmlErrorPage) {
StringBuilder sb = new StringBuilder();
for (String message : htmlErrorPage.messages) {
sb.append(message);
sb.append("<br/>");
}
String error = htmlErrorPage.error();
String errorBold = htmlErrorPage.errorBold();
if (error != null || errorBold != null) {
sb.append("<p>");
if (errorBold != null) {
sb.append("<strong>");
sb.append(errorBold);
sb.append("</strong>. ");
}
if (error != null) {
sb.append(error);
sb.append(".");
}
sb.append("</p>");
}
return sb.toString();
}
private record HtmlErrorPage(Locale locale,
int httpStatusCode,
String httpStatusReason,
String error,
String errorBold,
List<String> messages) {
}
}