be.olsson.slackappender.SlackAppender Maven / Gradle / Ivy
package be.olsson.slackappender;
import static java.util.Collections.emptyList;
import static java.util.Collections.unmodifiableMap;
import java.io.Closeable;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.Serializable;
import java.io.StringWriter;
import java.io.Writer;
import java.net.URL;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.core.Filter;
import org.apache.logging.log4j.core.Layout;
import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.appender.AbstractAppender;
import org.apache.logging.log4j.core.config.Node;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
import org.apache.logging.log4j.core.config.plugins.PluginElement;
import org.apache.logging.log4j.core.config.plugins.PluginFactory;
import org.apache.logging.log4j.core.layout.PatternLayout;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.squareup.okhttp.Call;
import com.squareup.okhttp.Callback;
import com.squareup.okhttp.MediaType;
import com.squareup.okhttp.OkHttpClient;
import com.squareup.okhttp.Request;
import com.squareup.okhttp.Request.Builder;
import com.squareup.okhttp.RequestBody;
import com.squareup.okhttp.Response;
@Plugin(name = "Slack", category = Node.CATEGORY, elementType = AbstractAppender.ELEMENT_TYPE, printObject = true)
public class SlackAppender extends AbstractAppender implements Closeable {
private static final MediaType JSON = MediaType.parse("application/json");
private static final Callback RESPONSE_CALLBACK = new Callback() {
@Override
public void onFailure(Request request, IOException e) {
e.printStackTrace();
}
@Override
public void onResponse(Response response) throws IOException {
response.body().string();
}
};
private static class MessageStat {
int countSinceLastLog;
long lastLogged;
long lastSeen;
}
private final OkHttpClient okHttpClient = new OkHttpClient();
private final Map iconMap;
private final Map colorMap;
private URL webhookUrl;
private String username;
private String channel;
private final Gson gson = new GsonBuilder().create();
private boolean meltdownProtection;
private int similarMessageSize;
private int timeBetweenSimilarLogsMs;
private int unmodifiedFirstLines = 5;
private List indentedPackagesToMute = Collections.emptyList();
@SuppressWarnings("SerializableInnerClassWithNonSerializableOuterClass")
private final LinkedHashMap similar = new LinkedHashMap() {
private static final long serialVersionUID = -4974367564537005090L;
@Override
protected boolean removeEldestEntry(Map.Entry eldest) {
return size() > similarMessageSize;
}
};
private SlackAppender(String name,
Filter filter,
Layout layout,
final URL webhookUrl,
final String username,
final String channel,
final boolean meltdownProtection,
final int similarMessageSize,
final int timeBetweenSimilarLogsMs) {
super(name, filter, layout, true);
setWebhookUrl(webhookUrl);
this.username = username;
this.channel = channel;
this.meltdownProtection = meltdownProtection;
this.similarMessageSize = similarMessageSize;
this.timeBetweenSimilarLogsMs = timeBetweenSimilarLogsMs;
Map iconMap = new HashMap<>();
iconMap.put(Level.TRACE.intLevel(), ":pawprints:");
iconMap.put(Level.DEBUG.intLevel(), ":beetle:");
iconMap.put(Level.INFO.intLevel(), ":suspect:");
iconMap.put(Level.WARN.intLevel(), ":goberserk:");
iconMap.put(Level.ERROR.intLevel(), ":feelsgood:");
iconMap.put(Level.FATAL.intLevel(), ":finnadie:");
this.iconMap = unmodifiableMap(iconMap);
Map colorMap = new HashMap<>();
colorMap.put(Level.TRACE.intLevel(), "#6f6d6d");
colorMap.put(Level.DEBUG.intLevel(), "#b5dae9");
colorMap.put(Level.INFO.intLevel(), "#5f9ea0");
colorMap.put(Level.WARN.intLevel(), "#ff9122");
colorMap.put(Level.ERROR.intLevel(), "#ff4444");
colorMap.put(Level.FATAL.intLevel(), "#b03e3c");
this.colorMap = unmodifiableMap(colorMap);
}
private class FilteredPrintWriter extends PrintWriter {
private boolean wroteEllipsize = false;
private int lineCount = 0;
private FilteredPrintWriter(final Writer out) {
super(out);
}
@Override
public void println(final Object objectToPrint) {
lineCount++;
String line = String.valueOf(objectToPrint);
if (lineCount >= unmodifiedFirstLines && !indentedPackagesToMute.isEmpty()) {
for (String packageToMute : indentedPackagesToMute) {
if (line.startsWith(packageToMute)) {
if (!wroteEllipsize) {
super.println("\t...");
}
wroteEllipsize = true;
return;
}
}
}
super.println(line.replace(' ', '\u00A0'));
}
}
@SuppressWarnings("ThrowableResultOfMethodCallIgnored")
@Override
public void append(final LogEvent event) {
if (!isAppenderDisabled() && event.getMessage() != null) {
SlackAppender.MessageStat stat = getMessageStat(event);
if (stat == null || System.currentTimeMillis() - stat.lastLogged > timeBetweenSimilarLogsMs) {
String logStatement = event.getMessage().getFormat();
SlackMessage slackMessage = new SlackMessage();
slackMessage.channel = channel;
slackMessage.iconEmoji = iconMap.get(event.getLevel().intLevel());
slackMessage.username = username;
slackMessage.attachments = new ArrayList<>();
Attachment attachment = new Attachment();
attachment.color = colorMap.get(event.getLevel().intLevel());
attachment.fallback = logStatement;
StringWriter stringWriter = new StringWriter();
appendMutedMessages(stat, stringWriter);
slackMessage.text = attachment.fallback;
stringWriter.append(event.getMessage().getFormattedMessage());
if (event.getThrown() != null) {
event.getThrown().printStackTrace(new FilteredPrintWriter(stringWriter));
}
attachment.text = stringWriter.toString();
slackMessage.attachments.add(attachment);
postSlackMessage(slackMessage);
}
}
}
private void appendMutedMessages(SlackAppender.MessageStat stat, StringWriter stringWriter) {
if (meltdownProtection) {
if (stat.countSinceLastLog > 1) {
stringWriter.append("Message was repeated ").append(String.valueOf(stat.countSinceLastLog)).append(" since last logging of message\n");
stat.countSinceLastLog = 0;
stat.lastLogged = System.currentTimeMillis();
}
}
}
private synchronized MessageStat getMessageStat(LogEvent event) {
if (meltdownProtection) {
String key = event.getMessage().getFormattedMessage();
MessageStat stat = similar.get(key);
if (stat == null) {
stat = new MessageStat();
}
similar.put(key, stat);
stat.countSinceLastLog++;
stat.lastSeen = System.currentTimeMillis();
return stat;
}
return null;
}
protected void postSlackMessage(SlackMessage slackMessage) {
try {
String payload = gson.toJson(slackMessage);
Request request = new Builder().url(webhookUrl).post(RequestBody.create(JSON, payload)).build();
Call call = okHttpClient.newCall(request);
call.enqueue(RESPONSE_CALLBACK);
} catch (Exception e) {
e.printStackTrace();
// Not much to do. Can't really log it via log4j
}
}
@Override
public void close() {
}
public URL getWebhookUrl() {
return webhookUrl;
}
public void setWebhookUrl(URL webhookUrl) {
this.webhookUrl = webhookUrl;
}
public String getChannel() {
return channel;
}
public void setChannel(String channel) {
this.channel = channel;
}
public void setUsername(final String username) {
this.username = username;
}
public String getUsername() {
return username;
}
public boolean isAppenderDisabled() {
return webhookUrl == null;
}
public boolean isMeltdownProtection() {
return meltdownProtection;
}
public void setMeltdownProtection(boolean meltdownProtection) {
this.meltdownProtection = meltdownProtection;
}
public int getSimilarMessageSize() {
return similarMessageSize;
}
public void setSimilarMessageSize(int similarMessageSize) {
this.similarMessageSize = similarMessageSize;
}
public int getTimeBetweenSimilarLogsMs() {
return timeBetweenSimilarLogsMs;
}
public void setTimeBetweenSimilarLogsMs(int timeBetweenSimilarLogsMs) {
this.timeBetweenSimilarLogsMs = timeBetweenSimilarLogsMs;
}
public void setPackagesToMute(final String packagesToMute) {
if (packagesToMute != null && !"".equals(packagesToMute.trim())) {
this.indentedPackagesToMute = new LinkedList<>();
for (String packageToMute : packagesToMute.split(",")) {
indentedPackagesToMute.add("\tat " + packageToMute);
}
} else {
this.indentedPackagesToMute = emptyList();
}
}
@PluginFactory
public static SlackAppender createAppender(
@PluginAttribute("name") String name,
@PluginElement("Layout") Layout layout,
@PluginElement("Filter") final Filter filter,
@PluginAttribute("webhookUrl") URL webhookUrl,
@PluginAttribute("channel") String channel,
@PluginAttribute(value = "username", defaultString = "Blazkowicz") String username,
@PluginAttribute(value = "meltdownProtection", defaultBoolean = true) boolean meltdownProtection,
@PluginAttribute(value = "similarMessageSize", defaultInt = 50) int similarMessageSize,
@PluginAttribute(value = "timeBetweenSimilarLogsMs", defaultInt = 60000) int timeBetweenSimilarLogsMs,
@PluginAttribute(value = "packagesToMute", defaultString = "") String packagesToMute) {
if (name == null) {
LOGGER.error("No name provided for MyCustomAppenderImpl");
return null;
}
if (layout == null) {
layout = PatternLayout.createDefaultLayout();
}
SlackAppender slackAppender = new SlackAppender(name, filter, layout, webhookUrl, username, channel, meltdownProtection, similarMessageSize, timeBetweenSimilarLogsMs);
slackAppender.setPackagesToMute(packagesToMute);
return slackAppender;
}
}
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