Keep buffer of Jdbc writer after connection loss

Fixes #91
tinylog-org · May 8, 2022 · e234a16 · e234a16
1 parent 5622635
commit e234a16
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Showing 2 changed files with 45 additions and 17 deletions.
diff --git a/tinylog-impl/src/main/java/org/tinylog/writers/JdbcWriter.java b/tinylog-impl/src/main/java/org/tinylog/writers/JdbcWriter.java
@@ -55,10 +55,10 @@ public final class JdbcWriter extends AbstractWriter {
  private final Object mutex;
  private final String sql;
  private final List<Token> tokens;
+ private final List<LogEntry> entries;
 
  private Connection connection;
  private PreparedStatement statement;
- private long batchCount;
  private long lostCount;
  private long reconnectTimestamp;
 
@@ -92,6 +92,7 @@ public JdbcWriter(final Map<String, String> properties) throws NamingException,
 
  mutex = getBooleanValue("writingthread") ? null : new Object();
 
+ entries = new ArrayList<LogEntry>();
  connection = connect(url, user, password);
  sql = renderSql(properties, connection.getMetaData().getIdentifierQuoteString());
  statement = connection.prepareStatement(sql);
@@ -154,13 +155,11 @@ public void close() throws SQLException {
  private void doWrite(final LogEntry logEntry) throws SQLException {
  if (checkConnection()) {
  if (batch) {
- batchCount += 1;
+ entries.add(logEntry);
  }
 
  try {
- for (int i = 0; i < tokens.size(); ++i) {
- tokens.get(i).apply(logEntry, statement, i + 1);
- }
+ applyLogEntry(logEntry);
  } catch (SQLException ex) {
  resetConnection();
  throw ex;
@@ -169,9 +168,9 @@ private void doWrite(final LogEntry logEntry) throws SQLException {
  try {
  if (batch) {
  statement.addBatch();
- if (batchCount >= MAX_BATCH_SIZE) {
+ if (entries.size() >= MAX_BATCH_SIZE) {
  statement.executeBatch();
- batchCount = 0;
+ entries.clear();
  }
  } else {
  statement.executeUpdate();
@@ -180,6 +179,8 @@ private void doWrite(final LogEntry logEntry) throws SQLException {
  resetConnection();
  throw ex;
  }
+ } else if (batch && entries.size() < MAX_BATCH_SIZE) {
+ entries.add(logEntry);
  } else {
  lostCount += 1;
  }
@@ -192,10 +193,10 @@ private void doWrite(final LogEntry logEntry) throws SQLException {
  * Database access failed
  */
  private void doFlush() throws SQLException {
- if (batchCount > 0) {
+ if (entries.size() > 0) {
  try {
  statement.executeBatch();
- batchCount = 0;
+ entries.clear();
  } catch (SQLException ex) {
  resetConnection();
  throw ex;
@@ -215,6 +216,10 @@ private void doClose() throws SQLException {
  doFlush();
  }
  } finally {
+ if (!entries.isEmpty()) {
+ lostCount += entries.size();
+ }
+
  if (lostCount > 0) {
  InternalLogger.log(Level.ERROR, "Lost log entries due to broken database connection: " + lostCount);
  }
@@ -237,8 +242,21 @@ private boolean checkConnection() {
  try {
  connection = connect(url, user, password);
  statement = connection.prepareStatement(sql);
- InternalLogger.log(Level.ERROR, "Lost log entries due to broken database connection: " + lostCount);
- lostCount = 0;
+
+ if (!entries.isEmpty()) {
+ for (LogEntry entry : entries) {
+ applyLogEntry(entry);
+ statement.addBatch();
+ }
+ statement.executeBatch();
+ entries.clear();
+ }
+
+ if (lostCount > 0) {
+ InternalLogger.log(Level.ERROR, "Lost log entries due to broken database connection: " + lostCount);
+ lostCount = 0;
+ }
+
  return true;
  } catch (NamingException ex) {
  long now = System.currentTimeMillis();
@@ -266,8 +284,7 @@ private void resetConnection() {
  if (reconnect) {
  closeConnectionSilently();
  statement = null;
- lostCount = batch ? batchCount : 1;
- batchCount = 0;
+ lostCount = batch ? 0 : 1;
  reconnectTimestamp = 0;
  }
  }
@@ -289,13 +306,25 @@ private void closeConnectionSilently() {
  }
  }
 
+ /**
+ * Applies a log entry to the current {@link PreparedStatement}.
+ *
+ * @param logEntry Log entry to apply
+ * @throws SQLException Failed to apply the passed log entry
+ */
+ private void applyLogEntry(final LogEntry logEntry) throws SQLException {
+ for (int i = 0; i < tokens.size(); ++i) {
+ tokens.get(i).apply(logEntry, statement, i + 1);
+ }
+ }
+
  /**
  * Establishes the connection to the database.
  *
  * @param url
  * JDBC or data source URL
  * @param user
- * User name for login (can be {@code null} if no login is required)
+ * Username for login (can be {@code null} if no login is required)
  * @param password
  * Password for login (can be {@code null} if no login is required)
  * @return Connection to the database

diff --git a/tinylog-impl/src/test/java/org/tinylog/writers/JdbcWriterTest.java b/tinylog-impl/src/test/java/org/tinylog/writers/JdbcWriterTest.java
@@ -496,11 +496,10 @@ public void repairBrokenBatchedConnection() throws NamingException, SQLException
  Thread.sleep(1000);
 
  writer.write(LogEntryBuilder.empty().message("Three").create());
- assertThat(systemStream.consumeErrorOutput()).containsOnlyOnce("ERROR").containsOnlyOnce("2");
-
  writer.close();
 
- assertThat(fetchTable(TABLE_NAME)).column("MESSAGE").containsValues("Three");
+ assertThat(fetchTable(TABLE_NAME)).column("MESSAGE").containsValues("One", "Two", "Three");
+ assertThat(systemStream.consumeErrorOutput()).isEmpty();
  }
 
  /**