argeo/init/logging/ThinLogging.java

   1 package org.argeo.init.logging;
   2
   3 import java.io.PrintStream;
   4 import java.io.Serializable;
   5 import java.lang.System.Logger;
   6 import java.lang.System.Logger.Level;
   7 import java.text.MessageFormat;
   8 import java.time.Instant;
   9 import java.util.Collections;
  10 import java.util.HashMap;
  11 import java.util.Iterator;
  12 import java.util.Map;
  13 import java.util.NavigableMap;
  14 import java.util.Objects;
  15 import java.util.ResourceBundle;
  16 import java.util.SortedMap;
  17 import java.util.StringTokenizer;
  18 import java.util.TreeMap;
  19 import java.util.concurrent.Executor;
  20 import java.util.concurrent.ExecutorService;
  21 import java.util.concurrent.Executors;
  22 import java.util.concurrent.Flow;
  23 import java.util.concurrent.Flow.Subscription;
  24 import java.util.concurrent.SubmissionPublisher;
  25 import java.util.concurrent.TimeUnit;
  26 import java.util.concurrent.atomic.AtomicLong;
  27 import java.util.function.Consumer;
  28
  29 /**
  30  * A thin logging system based on the {@link Logger} framework. It is a
  31  * {@link Consumer} of configuration, and can be registered as such.
  32  */
  33 class ThinLogging implements Consumer<Map<String, Object>> {
  34         final static String DEFAULT_LEVEL_NAME = "";
  35
  36         final static String DEFAULT_LEVEL_PROPERTY = "log";
  37         final static String LEVEL_PROPERTY_PREFIX = DEFAULT_LEVEL_PROPERTY + ".";
  38
  39         final static String JOURNALD_PROPERTY = "argeo.logging.journald";
  40         final static String CALL_LOCATION_PROPERTY = "argeo.logging.callLocation";
  41
  42         private final static AtomicLong nextEntry = new AtomicLong(0l);
  43
  44         // we don't synchronize maps on purpose as it would be
  45         // too expensive during normal operation
  46         // updates to the config may be shortly inconsistent
  47         private SortedMap<String, ThinLogger> loggers = new TreeMap<>();
  48         private NavigableMap<String, Level> levels = new TreeMap<>();
  49         private volatile boolean updatingConfiguration = false;
  50
  51         private final ExecutorService executor;
  52         private final LogEntryPublisher publisher;
  53
  54         private final boolean journald;
  55         private final Level callLocationLevel;
  56
  57         ThinLogging() {
  58                 executor = Executors.newCachedThreadPool((r) -> {
  59                         Thread t = new Thread(r);
  60                         t.setDaemon(true);
  61                         return t;
  62                 });
  63                 publisher = new LogEntryPublisher(executor, Flow.defaultBufferSize());
  64
  65                 PrintStreamSubscriber subscriber = new PrintStreamSubscriber();
  66                 publisher.subscribe(subscriber);
  67
  68                 Runtime.getRuntime().addShutdownHook(new Thread(() -> close(), "Log shutdown"));
  69
  70                 // initial default level
  71                 levels.put("", Level.WARNING);
  72
  73                 // Logging system config
  74                 // journald
  75
  76 //              Map<String, String> env = new TreeMap<>(System.getenv());
  77 //              for (String key : env.keySet()) {
  78 //                      System.out.println(key + "=" + env.get(key));
  79 //              }
  80
  81                 String journaldStr = System.getProperty(JOURNALD_PROPERTY, "auto");
  82                 switch (journaldStr) {
  83                 case "auto":
  84                         String systemdInvocationId = System.getenv("INVOCATION_ID");
  85                         if (systemdInvocationId != null) {// in systemd
  86                                 // check whether we are indirectly in a desktop app (e.g. eclipse)
  87                                 String desktopFilePid = System.getenv("GIO_LAUNCHED_DESKTOP_FILE_PID");
  88                                 if (desktopFilePid != null) {
  89                                         Long javaPid = ProcessHandle.current().pid();
  90                                         if (!javaPid.toString().equals(desktopFilePid)) {
  91                                                 journald = false;
  92                                                 break;
  93                                         }
  94                                 }
  95                                 journald = true;
  96                                 break;
  97                         }
  98                         journald = false;
  99                         break;
 100                 case "true":
 101                 case "on":
 102                         journald = true;
 103                         break;
 104                 case "false":
 105                 case "off":
 106                         journald = false;
 107                         break;
 108                 default:
 109                         throw new IllegalArgumentException(
 110                                         "Unsupported value '" + journaldStr + "' for property " + JOURNALD_PROPERTY);
 111                 }
 112
 113                 String callLocationStr = System.getProperty(CALL_LOCATION_PROPERTY, Level.WARNING.getName());
 114                 callLocationLevel = Level.valueOf(callLocationStr);
 115         }
 116
 117         private void close() {
 118                 publisher.close();
 119                 try {
 120                         // we ait a bit in order to make sure all messages are flushed
 121                         // TODO synchronize more efficiently
 122                         executor.awaitTermination(300, TimeUnit.MILLISECONDS);
 123                 } catch (InterruptedException e) {
 124                         // silent
 125                 }
 126         }
 127
 128         private Level computeApplicableLevel(String name) {
 129                 Map.Entry<String, Level> entry = levels.floorEntry(name);
 130                 assert entry != null;
 131                 return entry.getValue();
 132
 133         }
 134
 135 //      private boolean isLoggable(String name, Level level) {
 136 //              Objects.requireNonNull(name);
 137 //              Objects.requireNonNull(level);
 138 //
 139 //              if (updatingConfiguration) {
 140 //                      synchronized (levels) {
 141 //                              try {
 142 //                                      levels.wait();
 143 //                                      // TODO make exit more robust
 144 //                              } catch (InterruptedException e) {
 145 //                                      throw new IllegalStateException(e);
 146 //                              }
 147 //                      }
 148 //              }
 149 //
 150 //              return level.getSeverity() >= computeApplicableLevel(name).getSeverity();
 151 //      }
 152
 153         public Logger getLogger(String name, Module module) {
 154                 if (!loggers.containsKey(name)) {
 155                         ThinLogger logger = new ThinLogger(name, computeApplicableLevel(name));
 156                         loggers.put(name, logger);
 157                 }
 158                 return loggers.get(name);
 159         }
 160
 161         public void accept(Map<String, Object> configuration) {
 162                 synchronized (levels) {
 163                         updatingConfiguration = true;
 164
 165                         Map<String, Level> backup = new TreeMap<>(levels);
 166
 167                         boolean fullReset = configuration.containsKey(DEFAULT_LEVEL_PROPERTY);
 168                         try {
 169                                 properties: for (String property : configuration.keySet()) {
 170                                         if (!property.startsWith(LEVEL_PROPERTY_PREFIX))
 171                                                 continue properties;
 172                                         String levelStr = configuration.get(property).toString();
 173                                         Level level = Level.valueOf(levelStr);
 174                                         levels.put(property.substring(LEVEL_PROPERTY_PREFIX.length()), level);
 175                                 }
 176
 177                                 if (fullReset) {
 178                                         Iterator<Map.Entry<String, Level>> it = levels.entrySet().iterator();
 179                                         while (it.hasNext()) {
 180                                                 Map.Entry<String, Level> entry = it.next();
 181                                                 String name = entry.getKey();
 182                                                 if (!configuration.containsKey(LEVEL_PROPERTY_PREFIX + name)) {
 183                                                         it.remove();
 184                                                 }
 185                                         }
 186                                         Level newDefaultLevel = Level.valueOf(configuration.get(DEFAULT_LEVEL_PROPERTY).toString());
 187                                         levels.put(DEFAULT_LEVEL_NAME, newDefaultLevel);
 188                                         // TODO notify everyone?
 189                                 }
 190                                 assert levels.containsKey(DEFAULT_LEVEL_NAME);
 191
 192                                 // recompute all levels
 193                                 for (String name : loggers.keySet()) {
 194                                         ThinLogger logger = loggers.get(name);
 195                                         logger.setLevel(computeApplicableLevel(name));
 196                                 }
 197                         } catch (IllegalArgumentException e) {
 198                                 e.printStackTrace();
 199                                 levels.clear();
 200                                 levels.putAll(backup);
 201                         }
 202                         updatingConfiguration = false;
 203                         levels.notifyAll();
 204                 }
 205
 206         }
 207
 208         Flow.Publisher<Map<String, Serializable>> getLogEntryPublisher() {
 209                 return publisher;
 210         }
 211
 212         Map<String, Level> getLevels() {
 213                 return Collections.unmodifiableNavigableMap(levels);
 214         }
 215
 216         /*
 217          * INTERNAL CLASSES
 218          */
 219
 220         private class ThinLogger implements System.Logger {
 221                 private final String name;
 222
 223                 private Level level;
 224
 225                 protected ThinLogger(String name, Level level) {
 226                         assert Objects.nonNull(name);
 227                         this.name = name;
 228                         this.level = level;
 229                 }
 230
 231                 @Override
 232                 public String getName() {
 233                         return name;
 234                 }
 235
 236                 @Override
 237                 public boolean isLoggable(Level level) {
 238                         return level.getSeverity() >= getLevel().getSeverity();
 239                         // TODO optimise by referencing the applicable level in this class?
 240 //                      return ThinLogging.this.isLoggable(name, level);
 241                 }
 242
 243                 private Level getLevel() {
 244                         if (updatingConfiguration) {
 245                                 synchronized (levels) {
 246                                         try {
 247                                                 levels.wait();
 248                                                 // TODO make exit more robust
 249                                         } catch (InterruptedException e) {
 250                                                 throw new IllegalStateException(e);
 251                                         }
 252                                 }
 253                         }
 254                         return level;
 255                 }
 256
 257                 @Override
 258                 public void log(Level level, ResourceBundle bundle, String msg, Throwable thrown) {
 259                         if (!isLoggable(level))
 260                                 return;
 261                         // measure timestamp first
 262                         Instant now = Instant.now();
 263                         Thread thread = Thread.currentThread();
 264                         publisher.log(this, level, bundle, msg, now, thread, thrown, findCallLocation(level, thread));
 265                 }
 266
 267                 @Override
 268                 public void log(Level level, ResourceBundle bundle, String format, Object... params) {
 269                         if (!isLoggable(level))
 270                                 return;
 271                         // measure timestamp first
 272                         Instant now = Instant.now();
 273                         Thread thread = Thread.currentThread();
 274
 275                         // NOTE: this is the method called when logging a plain message without
 276                         // exception, so it should be considered as a format only when args are not null
 277                         String msg = params == null ? format : MessageFormat.format(format, params);
 278                         publisher.log(this, level, bundle, msg, now, thread, (Throwable) null, findCallLocation(level, thread));
 279                 }
 280
 281                 private void setLevel(Level level) {
 282                         this.level = level;
 283                 }
 284
 285                 private StackTraceElement findCallLocation(Level level, Thread thread) {
 286                         assert level != null;
 287                         assert thread != null;
 288                         StackTraceElement callLocation = null;
 289                         if (level.getSeverity() >= callLocationLevel.getSeverity()) {
 290                                 StackTraceElement[] stack = thread.getStackTrace();
 291                                 int lowestLoggerInterface = 0;
 292                                 stack: for (int i = 2; i < stack.length; i++) {
 293                                         String className = stack[i].getClassName();
 294                                         switch (className) {
 295                                         // TODO make it more configurable
 296                                         case "java.lang.System$Logger":
 297                                         case "java.util.logging.Logger":
 298                                         case "org.apache.commons.logging.Log":
 299                                         case "org.osgi.service.log.Logger":
 300                                         case "org.argeo.cms.Log":
 301                                         case "org.slf4j.impl.ArgeoLogger":
 302                                         case "org.eclipse.jetty.util.log.Slf4jLog":
 303                                                 lowestLoggerInterface = i;
 304                                                 continue stack;
 305                                         default:
 306                                         }
 307                                 }
 308                                 if (stack.length > lowestLoggerInterface + 1)
 309                                         callLocation = stack[lowestLoggerInterface + 1];
 310                         }
 311                         return callLocation;
 312                 }
 313
 314         }
 315
 316         private final static String KEY_LOGGER = Logger.class.getName();
 317         private final static String KEY_LEVEL = Level.class.getName();
 318         private final static String KEY_MSG = String.class.getName();
 319         private final static String KEY_THROWABLE = Throwable.class.getName();
 320         private final static String KEY_INSTANT = Instant.class.getName();
 321         private final static String KEY_CALL_LOCATION = StackTraceElement.class.getName();
 322         private final static String KEY_THREAD = Thread.class.getName();
 323
 324         private class LogEntryPublisher extends SubmissionPublisher<Map<String, Serializable>> {
 325
 326                 private LogEntryPublisher(Executor executor, int maxBufferCapacity) {
 327                         super(executor, maxBufferCapacity);
 328                 }
 329
 330                 private void log(ThinLogger logger, Level level, ResourceBundle bundle, String msg, Instant instant,
 331                                 Thread thread, Throwable thrown, StackTraceElement callLocation) {
 332                         assert level != null;
 333                         assert logger != null;
 334                         assert msg != null;
 335                         assert instant != null;
 336                         assert thread != null;
 337
 338                         final long sequence = nextEntry.incrementAndGet();
 339
 340                         Map<String, Serializable> logEntry = new LogEntryMap(sequence);
 341
 342                         // same object as key class name
 343                         logEntry.put(KEY_LEVEL, level);
 344                         logEntry.put(KEY_MSG, msg);
 345                         logEntry.put(KEY_INSTANT, instant);
 346                         if (thrown != null)
 347                                 logEntry.put(KEY_THROWABLE, thrown);
 348                         if (callLocation != null)
 349                                 logEntry.put(KEY_CALL_LOCATION, callLocation);
 350
 351                         // object is a string
 352                         logEntry.put(KEY_LOGGER, logger.getName());
 353                         logEntry.put(KEY_THREAD, thread.getName());
 354
 355                         // should be unmodifiable for security reasons
 356                         submit(Collections.unmodifiableMap(logEntry));
 357                 }
 358
 359         }
 360
 361         /**
 362          * An internal optimisation for collections. It should not be referred to
 363          * directly as a type.
 364          */
 365         // TODO optimise memory with a custom map implementation?
 366         // but access may be slower
 367         private static class LogEntryMap extends HashMap<String, Serializable> {
 368                 private static final long serialVersionUID = 7361434381922521356L;
 369
 370                 private final long sequence;
 371
 372                 private LogEntryMap(long sequence) {
 373                         // maximum 7 fields, so using default load factor 0.75
 374                         // an initial size of 10 should prevent rehashing (7 / 0.75 ~ 9.333)
 375                         // see HashMap class description for more details
 376                         super(10, 0.75f);
 377                         this.sequence = sequence;
 378                 }
 379
 380                 @Override
 381                 public boolean equals(Object o) {
 382                         if (o instanceof LogEntryMap)
 383                                 return sequence == ((LogEntryMap) o).sequence;
 384                         else if (o instanceof Map) {
 385                                 Map<?, ?> map = (Map<?, ?>) o;
 386                                 return get(KEY_INSTANT).equals(map.get(KEY_INSTANT)) && get(KEY_THREAD).equals(map.get(KEY_THREAD));
 387                         } else
 388                                 return false;
 389                 }
 390
 391                 @Override
 392                 public int hashCode() {
 393                         return (int) sequence;
 394                 }
 395
 396         }
 397
 398         private class PrintStreamSubscriber implements Flow.Subscriber<Map<String, Serializable>> {
 399                 private PrintStream out;
 400                 private PrintStream err;
 401                 private int writeToErrLevel = Level.WARNING.getSeverity();
 402
 403                 protected PrintStreamSubscriber() {
 404                         this(System.out, System.err);
 405                 }
 406
 407                 protected PrintStreamSubscriber(PrintStream out, PrintStream err) {
 408                         this.out = out;
 409                         this.err = err;
 410                 }
 411
 412                 private Level getLevel(Map<String, Serializable> logEntry) {
 413                         return (Level) logEntry.get(KEY_LEVEL);
 414                 }
 415
 416                 @Override
 417                 public void onSubscribe(Subscription subscription) {
 418                         subscription.request(Long.MAX_VALUE);
 419                 }
 420
 421                 @Override
 422                 public void onNext(Map<String, Serializable> item) {
 423                         if (getLevel(item).getSeverity() >= writeToErrLevel) {
 424                                 err.print(toPrint(item));
 425                         } else {
 426                                 out.print(toPrint(item));
 427                         }
 428                         // TODO flush for journald?
 429                 }
 430
 431                 @Override
 432                 public void onError(Throwable throwable) {
 433                         throwable.printStackTrace(err);
 434                 }
 435
 436                 @Override
 437                 public void onComplete() {
 438                         out.flush();
 439                         err.flush();
 440                 }
 441
 442                 protected String firstLinePrefix(Map<String, Serializable> logEntry) {
 443                         Level level = getLevel(logEntry);
 444                         String spaces;
 445                         switch (level) {
 446                         case ERROR:
 447                         case DEBUG:
 448                         case TRACE:
 449                                 spaces = "   ";
 450                                 break;
 451                         case INFO:
 452                                 spaces = "    ";
 453                                 break;
 454                         case WARNING:
 455                                 spaces = " ";
 456                                 break;
 457                         case ALL:
 458                                 spaces = "     ";
 459                                 break;
 460                         default:
 461                                 throw new IllegalArgumentException("Unsupported level " + level);
 462                         }
 463                         return journald ? linePrefix(logEntry) : logEntry.get(KEY_INSTANT) + " " + level + spaces;
 464                 }
 465
 466                 protected String firstLineSuffix(Map<String, Serializable> logEntry) {
 467                         return " - " + (logEntry.containsKey(KEY_CALL_LOCATION) ? logEntry.get(KEY_CALL_LOCATION)
 468                                         : logEntry.get(KEY_LOGGER)) + " [" + logEntry.get(KEY_THREAD) + "]";
 469                 }
 470
 471                 protected String linePrefix(Map<String, Serializable> logEntry) {
 472                         return journald ? "<" + levelToJournald(getLevel(logEntry)) + ">" : "";
 473                 }
 474
 475                 protected int levelToJournald(Level level) {
 476                         int severity = level.getSeverity();
 477                         if (severity >= Level.ERROR.getSeverity())
 478                                 return 3;
 479                         else if (severity >= Level.WARNING.getSeverity())
 480                                 return 4;
 481                         else if (severity >= Level.INFO.getSeverity())
 482                                 return 6;
 483                         else
 484                                 return 7;
 485                 }
 486
 487                 protected String toPrint(Map<String, Serializable> logEntry) {
 488                         StringBuilder sb = new StringBuilder();
 489                         StringTokenizer st = new StringTokenizer((String) logEntry.get(KEY_MSG), "\r\n");
 490                         assert st.hasMoreTokens();
 491
 492                         // first line
 493                         String firstLine = st.nextToken();
 494                         sb.append(firstLinePrefix(logEntry));
 495                         sb.append(firstLine);
 496                         sb.append(firstLineSuffix(logEntry));
 497                         sb.append('\n');
 498
 499                         // other lines
 500                         String prefix = linePrefix(logEntry);
 501                         while (st.hasMoreTokens()) {
 502                                 sb.append(prefix);
 503                                 sb.append(st.nextToken());
 504                                 sb.append('\n');
 505                         }
 506
 507                         if (logEntry.containsKey(KEY_THROWABLE)) {
 508                                 Throwable throwable = (Throwable) logEntry.get(KEY_THROWABLE);
 509                                 sb.append(prefix);
 510                                 addThrowable(sb, prefix, throwable);
 511                         }
 512                         return sb.toString();
 513                 }
 514
 515                 protected void addThrowable(StringBuilder sb, String prefix, Throwable throwable) {
 516                         sb.append(throwable.getClass().getName());
 517                         sb.append(": ");
 518                         sb.append(throwable.getMessage());
 519                         sb.append('\n');
 520                         for (StackTraceElement ste : throwable.getStackTrace()) {
 521                                 sb.append(prefix);
 522                                 sb.append(ste.toString());
 523                                 sb.append('\n');
 524                         }
 525                         if (throwable.getCause() != null) {
 526                                 sb.append(prefix);
 527                                 sb.append("caused by ");
 528                                 addThrowable(sb, prefix, throwable.getCause());
 529                         }
 530                 }
 531         }
 532
 533         public static void main(String args[]) {
 534                 Logger logger = System.getLogger(ThinLogging.class.getName());
 535                 logger.log(Logger.Level.ALL, "Log all");
 536                 logger.log(Logger.Level.TRACE, "Multi\nline\ntrace");
 537                 logger.log(Logger.Level.DEBUG, "Log debug");
 538                 logger.log(Logger.Level.INFO, "Log info");
 539                 logger.log(Logger.Level.WARNING, "Log warning");
 540                 logger.log(Logger.Level.ERROR, "Log exception", new Throwable());
 541         }
 542
 543 }