org.glowroot.central.GlowrootServlet Maven / Gradle / Ivy
/*
* Copyright 2017-2019 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 org.glowroot.central;
import java.io.File;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.nio.file.Files;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.google.common.base.Strings;
import com.google.common.collect.ImmutableList;
import com.google.common.io.CharStreams;
import io.netty.buffer.ByteBuf;
import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
import org.checkerframework.checker.nullness.qual.Nullable;
import org.glowroot.ui.ChunkSource;
import org.glowroot.ui.ChunkSource.ChunkCopier;
import org.glowroot.ui.CommonHandler;
import org.glowroot.ui.CommonHandler.CommonRequest;
import org.glowroot.ui.CommonHandler.CommonResponse;
import static com.google.common.base.Preconditions.checkNotNull;
import static java.nio.charset.StandardCharsets.UTF_8;
// loadOnStartup is needed so that gRPC listener starts right away
@WebServlet(value = "/*", loadOnStartup = 0)
@SuppressWarnings("serial")
public class GlowrootServlet extends HttpServlet {
private volatile @MonotonicNonNull CentralModule centralModule;
private volatile @MonotonicNonNull CommonHandler commonHandler;
@Override
public void init(ServletConfig config) throws ServletException {
try {
File centralDir = getCentralDir();
File propFile = new File(centralDir, "glowroot-central.properties");
if (!propFile.exists()) {
Files.copy(config.getServletContext().getResourceAsStream(
"/META-INF/glowroot-central.properties"), propFile.toPath());
}
centralModule =
CentralModule.createForServletContainer(centralDir, config.getServletContext());
commonHandler = centralModule.getCommonHandler();
} catch (Exception e) {
throw new ServletException(e);
}
}
@Override
public void destroy() {
if (centralModule != null) {
centralModule.shutdown(false);
}
}
@Override
public void service(ServletRequest req, ServletResponse res)
throws ServletException, IOException {
HttpServletRequest request = (HttpServletRequest) req;
HttpServletResponse response = (HttpServletResponse) res;
CommonResponse commonResponse;
try {
commonResponse = checkNotNull(commonHandler).handle(new ServletReq(request));
} catch (Exception e) {
throw new ServletException(e);
}
response.setStatus(commonResponse.getStatus().code());
for (Map.Entry entry : commonResponse.getHeaders()) {
response.addHeader(entry.getKey(), entry.getValue());
}
Object content = commonResponse.getContent();
if (content instanceof String) {
response.getWriter().write((String) content);
response.flushBuffer();
} else if (content instanceof ByteBuf) {
ByteBuf buf = (ByteBuf) content;
byte[] bytes = new byte[buf.readableBytes()];
buf.readBytes(bytes);
response.getOutputStream().write(bytes);
response.flushBuffer();
} else if (content instanceof ChunkSource) {
ChunkSource chunkSource = (ChunkSource) content;
String zipFileName = commonResponse.getZipFileName();
if (zipFileName == null) {
PrintWriter out = res.getWriter();
ChunkCopier copier = chunkSource.getCopier(out);
while (copier.copyNext()) {
}
out.flush();
} else {
ServletOutputStream out = res.getOutputStream();
ZipOutputStream zipOut = new ZipOutputStream(out);
zipOut.putNextEntry(new ZipEntry(zipFileName + ".html"));
OutputStreamWriter zipWriter = new OutputStreamWriter(zipOut, UTF_8);
ChunkCopier copier = chunkSource.getCopier(zipWriter);
while (copier.copyNext()) {
}
zipWriter.close();
out.flush();
}
} else {
throw new IllegalStateException("Unexpected content: " + content.getClass().getName());
}
}
private static File getCentralDir() throws IOException {
String centralDirPath = System.getProperty("glowroot.central.dir");
if (Strings.isNullOrEmpty(centralDirPath)) {
return getDefaultCentralDir();
}
File centralDir = new File(centralDirPath);
centralDir.mkdirs();
if (!centralDir.isDirectory()) {
// not using logger since the central dir is needed to set up the logger
return getDefaultCentralDir();
}
return centralDir;
}
private static File getDefaultCentralDir() throws IOException {
File centralDir = new File("glowroot-central");
if (!centralDir.exists()) {
// upgrade from 0.9.11 to 0.9.12 if needed
File oldCentralDir = new File("glowroot");
if (oldCentralDir.exists() && !oldCentralDir.renameTo(centralDir)) {
throw new IOException("Unable to rename glowroot central directory from '"
+ oldCentralDir.getAbsolutePath() + "' to '" + centralDir.getAbsolutePath()
+ "'");
}
}
centralDir.mkdirs();
if (!centralDir.isDirectory()) {
throw new IOException("Could not create directory: " + centralDir.getAbsolutePath());
}
return centralDir;
}
private static class ServletReq implements CommonRequest {
private final HttpServletRequest request;
private ServletReq(HttpServletRequest request) {
this.request = request;
}
@Override
public String getMethod() {
return request.getMethod();
}
// includes context path
@Override
public String getUri() {
return request.getRequestURI();
}
@Override
public String getContextPath() {
return request.getContextPath();
}
// does not include context path
@Override
public String getPath() {
return request.getPathInfo();
}
@Override
public @Nullable String getHeader(CharSequence name) {
return request.getHeader(name.toString());
}
@Override
public Map> getParameters() {
Map> parameters = new HashMap<>();
for (Map.Entry entry : request.getParameterMap().entrySet()) {
parameters.put(entry.getKey(), Arrays.asList(entry.getValue()));
}
return parameters;
}
@Override
public List getParameters(String name) {
String[] values = request.getParameterValues(name);
if (values == null) {
return ImmutableList.of();
} else {
return Arrays.asList(values);
}
}
@Override
public String getContent() throws IOException {
return CharStreams.toString(request.getReader());
}
}
}