Introduce MigrationContext to be prepared for JDBC migration refactor

ebean-migration/src/main/java/io/ebean/migration/MigrationContext.java

@@ -0,0 +1,41 @@
+package io.ebean.migration;
+
+import java.sql.Connection;
+
+/**
+ * The current context while a migration runs.
+ * <p>
+ * This is used to provide meta-informations in JDBC migrations and mainly provides a read-only access
+ * to a subset of MigrationConfig.
+ * <p>
+ * It is possible to provide an extended implementation in <code>MigrationEngine.run(context)</code>,
+ * which is accessible in JdbcMigration. So you can create a EbeanMigrationContext, so that you can
+ * access the current ebean server in the JDBC migration.
+ *
+ * @author Roland Praml, FOCONIS AG
+ */
+public interface MigrationContext {
+  /**
+   * The current connection. Note: During migration, this connection is always the same.
+   * You must not close this connection!
+   */
+  Connection connection();
+
+  /**
+   * The migration path of SQL migrations. You can use this, to load additional SQL resources
+   * in your JDBC migration or determine, if this JDBC migration is for a particular path.
+   * This can be used if you have multiple ebean servers for different databases.
+   */
+  String migrationPath();
+
+  /**
+   * The platform of the current migration run. (e.g. <code>sqlserver17</code>)
+   */
+  String platform();
+
+  /**
+   * The base platform of the current migration run. (e.g. <code>sqlserver</code>)
+   */
+  String basePlatform();
+
+}

ebean-migration/src/main/java/io/ebean/migration/runner/DefaultMigrationContext.java

@@ -0,0 +1,45 @@
+package io.ebean.migration.runner;
+
+import io.ebean.migration.MigrationConfig;
+import io.ebean.migration.MigrationContext;
+
+import java.sql.Connection;
+
+/**
+ * A default implementation of the MigrationContext.
+ *
+ * @author Roland Praml, FOCONIS AG
+ */
+public class DefaultMigrationContext implements MigrationContext {
+  private final Connection connection;
+  private final String migrationPath;
+  private final String platform;
+  private final String basePlatform;
+
+  public DefaultMigrationContext(MigrationConfig config, Connection connection) {
+    this.connection = connection;
+    this.migrationPath = config.getMigrationPath();
+    this.platform = config.getPlatform();
+    this.basePlatform = config.getBasePlatform();
+  }
+
+  @Override
+  public Connection connection() {
+    return connection;
+  }
+
+  @Override
+  public String migrationPath() {
+    return migrationPath;
+  }
+
+  @Override
+  public String platform() {
+    return platform;
+  }
+
+  @Override
+  public String basePlatform() {
+    return basePlatform;
+  }
+}

ebean-migration/src/main/java/io/ebean/migration/runner/FirstCheck.java

@@ -1,6 +1,7 @@
 package io.ebean.migration.runner;
 
 import io.ebean.migration.MigrationConfig;
+import io.ebean.migration.MigrationContext;
 
 import java.sql.Connection;
 import java.sql.SQLException;
@@ -15,17 +16,17 @@ final class FirstCheck {
 
   final MigrationConfig config;
   final MigrationPlatform platform;
-  final Connection connection;
+  final MigrationContext context;
   final String schema;
   final String table;
   final String sqlTable;
   boolean tableKnownToExist;
   private int count;
 
-  FirstCheck(MigrationConfig config, Connection connection, MigrationPlatform platform) {
+  FirstCheck(MigrationConfig config, MigrationContext context, MigrationPlatform platform) {
     this.config = config;
     this.platform = platform;
-    this.connection = connection;
+    this.context = context;
     this.schema = config.getDbSchema();
     this.table = config.getMetaTable();
     this.sqlTable = schema != null ? schema + '.' + table : table;
@@ -80,7 +81,7 @@ private int checksumFor(LocalMigrationResource local) {
   }
 
   List<MigrationMetaRow> fastRead() throws SQLException {
-    return platform.fastReadMigrations(sqlTable, connection);
+    return platform.fastReadMigrations(sqlTable, context.connection());
   }
 
   int count() {

ebean-migration/src/main/java/io/ebean/migration/runner/MigrationEngine.java

@@ -2,6 +2,7 @@
 
 import io.avaje.applog.AppLog;
 import io.ebean.migration.MigrationConfig;
+import io.ebean.migration.MigrationContext;
 import io.ebean.migration.MigrationException;
 import io.ebean.migration.MigrationResource;
 
@@ -35,51 +36,63 @@ public MigrationEngine(MigrationConfig migrationConfig, boolean checkStateOnly)
 
   /**
    * Run the migrations if there are any that need running.
+   *
+   * @param connection the connection to run on. Note the connection will be closed.
    */
   public List<MigrationResource> run(Connection connection) {
     try {
-      long startMs = System.currentTimeMillis();
-      LocalMigrationResources resources = new LocalMigrationResources(migrationConfig);
-      if (!resources.readResources() && !resources.readInitResources()) {
-        log.log(DEBUG, "no migrations to check");
-        return emptyList();
-      }
-      long splitMs = System.currentTimeMillis() - startMs;
-      final var platform = derivePlatform(migrationConfig, connection);
-      final var firstCheck = new FirstCheck(migrationConfig, connection, platform);
-      if (fastMode && firstCheck.fastModeCheck(resources.versions())) {
-        long checkMs = System.currentTimeMillis() - startMs;
-        log.log(INFO, "DB migrations completed in {0}ms - totalMigrations:{1} readResources:{2}ms", checkMs, firstCheck.count(), splitMs);
-        return emptyList();
-      }
-      // ensure running with autoCommit false
-      setAutoCommitFalse(connection);
-
-      final MigrationTable table = initialiseMigrationTable(firstCheck, connection);
-      try {
-        List<MigrationResource> result = runMigrations(table, resources.versions());
-        connection.commit();
-        if (!checkStateOnly) {
-          long commitMs = System.currentTimeMillis();
-          log.log(INFO, "DB migrations completed in {0}ms - executed:{1} totalMigrations:{2} mode:{3}", (commitMs - startMs), table.count(), table.size(), table.mode());
-          int countNonTransactional = table.runNonTransactional();
-          if (countNonTransactional > 0) {
-            log.log(INFO, "Non-transactional DB migrations completed in {0}ms - executed:{1}", (System.currentTimeMillis() - commitMs), countNonTransactional);
-          }
+      return run(new DefaultMigrationContext(migrationConfig, connection));
+    } finally {
+      close(connection);
+    }
+  }
+
+  /**
+   * Run the migrations if there are any that need running. (Does not close connection)
+   */
+  public List<MigrationResource> run(MigrationContext context) {
+
+    long startMs = System.currentTimeMillis();
+    LocalMigrationResources resources = new LocalMigrationResources(migrationConfig);
+    if (!resources.readResources() && !resources.readInitResources()) {
+      log.log(DEBUG, "no migrations to check");
+      return emptyList();
+    }
+
+    var connection = context.connection();
+    long splitMs = System.currentTimeMillis() - startMs;
+    final var platform = derivePlatform(migrationConfig, connection);
+    final var firstCheck = new FirstCheck(migrationConfig, context, platform);
+    if (fastMode && firstCheck.fastModeCheck(resources.versions())) {
+      long checkMs = System.currentTimeMillis() - startMs;
+      log.log(INFO, "DB migrations completed in {0}ms - totalMigrations:{1} readResources:{2}ms", checkMs, firstCheck.count(), splitMs);
+      return emptyList();
+    }
+    // ensure running with autoCommit false
+    setAutoCommitFalse(connection);
+
+    final MigrationTable table = initialiseMigrationTable(firstCheck, connection);
+    try {
+      List<MigrationResource> result = runMigrations(table, resources.versions());
+      connection.commit();
+      if (!checkStateOnly) {
+        long commitMs = System.currentTimeMillis();
+        log.log(INFO, "DB migrations completed in {0}ms - executed:{1} totalMigrations:{2} mode:{3}", (commitMs - startMs), table.count(), table.size(), table.mode());
+        int countNonTransactional = table.runNonTransactional();
+        if (countNonTransactional > 0) {
+          log.log(INFO, "Non-transactional DB migrations completed in {0}ms - executed:{1}", (System.currentTimeMillis() - commitMs), countNonTransactional);
         }
-        return result;
-      } catch (MigrationException e) {
-        rollback(connection);
-        throw e;
-      } catch (Throwable e) {
-        log.log(ERROR, "Perform rollback due to DB migration error", e);
-        rollback(connection);
-        throw new MigrationException("Error running DB migrations", e);
-      } finally {
-        table.unlockMigrationTable();
       }
+      return result;
+    } catch (MigrationException e) {
+      rollback(connection);
+      throw e;
+    } catch (Throwable e) {
+      log.log(ERROR, "Perform rollback due to DB migration error", e);
+      rollback(connection);
+      throw new MigrationException("Error running DB migrations", e);
     } finally {
-      close(connection);
+      table.unlockMigrationTable();
     }
   }
 

ebean-migration/src/main/java/io/ebean/migration/runner/MigrationTable.java

@@ -26,7 +26,7 @@ final class MigrationTable {
   private static final int AUTO_PATCH_CHECKSUM = -1;
 
   private final MigrationConfig config;
-  private final Connection connection;
+  private final MigrationContext context;
   private final boolean checkStateOnly;
   private boolean earlyChecksumMode;
   private final MigrationPlatform platform;
@@ -72,18 +72,18 @@ final class MigrationTable {
   private int executionCount;
   private boolean patchLegacyChecksums;
   private MigrationMetaRow initMetaRow;
-  private boolean tableKnownToExist;
+  private final boolean tableKnownToExist;
 
   public MigrationTable(FirstCheck firstCheck, boolean checkStateOnly) {
     this.config = firstCheck.config;
     this.platform = firstCheck.platform;
-    this.connection = firstCheck.connection;
+    this.context = firstCheck.context;
     this.schema = firstCheck.schema;
     this.table = firstCheck.table;
     this.sqlTable = firstCheck.sqlTable;
     this.tableKnownToExist = firstCheck.tableKnownToExist;
 
-    this.scriptRunner = new MigrationScriptRunner(connection, platform);
+    this.scriptRunner = new MigrationScriptRunner(context.connection(), platform);
     this.checkStateOnly = checkStateOnly;
     this.earlyChecksumMode = config.isEarlyChecksumMode();
     this.migrations = new LinkedHashMap<>();
@@ -142,7 +142,7 @@ private ScriptTransform createScriptTransform(MigrationConfig config) {
   void createIfNeededAndLock() throws SQLException, IOException {
     SQLException suppressedException = null;
     if (!tableKnownToExist) {
-      MigrationSchema.createIfNeeded(config, connection);
+      MigrationSchema.createIfNeeded(config, context.connection());
       if (!tableExists()) {
         try {
           createTable();
@@ -174,14 +174,14 @@ void createIfNeededAndLock() throws SQLException, IOException {
    * contain all the executed migrations in that case.
    */
   private void obtainLockWithWait() throws SQLException {
-    platform.lockMigrationTable(sqlTable, connection);
+    platform.lockMigrationTable(sqlTable, context.connection());
   }
 
   /**
    * Release a lock on the migration table (MySql, MariaDB only).
    */
   void unlockMigrationTable() {
-    platform.unlockMigrationTable(sqlTable, connection);
+    platform.unlockMigrationTable(sqlTable, context.connection());
   }
 
   /**
@@ -191,12 +191,13 @@ void unlockMigrationTable() {
    * executed during the wait for the lock.
    */
   private void readExistingMigrations() throws SQLException {
-    for (MigrationMetaRow metaRow : platform.readExistingMigrations(sqlTable, connection)) {
+    for (MigrationMetaRow metaRow : platform.readExistingMigrations(sqlTable, context.connection())) {
       addMigration(metaRow.version(), metaRow);
     }
   }
 
   void createTable() throws IOException, SQLException {
+    Connection connection = context.connection();
     try {
       scriptRunner.runScript(createTableDdl(), "create migration table");
       createInitMetaRow().executeInsert(connection, insertSql);
@@ -253,6 +254,7 @@ private ClassLoader classLoader() {
    * Return true if the table exists.
    */
   boolean tableExists() throws SQLException {
+    Connection connection = context.connection();
     String migTable = table;
     DatabaseMetaData metaData = connection.getMetaData();
     if (metaData.storesUpperCaseIdentifiers()) {
@@ -351,7 +353,7 @@ boolean skipMigration(int checksum, int checksum2, LocalMigrationResource local,
     } else if (patchLegacyChecksums && (existing.checksum() == checksum2 || checksum2 == AUTO_PATCH_CHECKSUM)) {
       if (!checkStateOnly) {
         log.log(INFO, "Auto patch migration, set early mode checksum on {0} to {1,number} from {2,number}", local.location(), checksum, existing.checksum());
-        existing.resetChecksum(checksum, connection, updateChecksumSql);
+        existing.resetChecksum(checksum, context.connection(), updateChecksumSql);
       }
       return true;
 
@@ -373,7 +375,7 @@ boolean skipMigration(int checksum, int checksum2, LocalMigrationResource local,
   private boolean patchResetChecksum(MigrationMetaRow existing, int newChecksum) throws SQLException {
     if (isResetOnVersion(existing.version())) {
       if (!checkStateOnly) {
-        existing.resetChecksum(newChecksum, connection, updateChecksumSql);
+        existing.resetChecksum(newChecksum, context.connection(), updateChecksumSql);
       }
       return true;
     } else {
@@ -405,7 +407,7 @@ private void executeMigration(LocalMigrationResource local, String script, int c
       }
       if (existing != null) {
         existing.rerun(checksum, exeMillis, envUserName, runOn);
-        existing.executeUpdate(connection, updateSql);
+        existing.executeUpdate(context.connection(), updateSql);
       } else {
         insertIntoHistory(local, checksum, exeMillis);
       }
@@ -424,7 +426,7 @@ private long executeMigration(LocalMigrationResource local, String script) throw
     if (local instanceof LocalJdbcMigrationResource) {
       JdbcMigration migration = ((LocalJdbcMigrationResource) local).migration();
       log.log(INFO, "Executing jdbc migration version: {0} - {1}", local.version(), migration);
-      migration.migrate(connection);
+      migration.migrate(context.connection());
     } else {
       log.log(DEBUG, "run migration {0}", local.location());
       scriptRunner.runScript(script, "run migration version: " + local.version());
@@ -435,7 +437,7 @@ private long executeMigration(LocalMigrationResource local, String script) throw
 
   private void insertIntoHistory(LocalMigrationResource local, int checksum, long exeMillis) throws SQLException {
     MigrationMetaRow metaRow = createMetaRow(local, checksum, exeMillis);
-    metaRow.executeInsert(connection, insertSql);
+    metaRow.executeInsert(context.connection(), insertSql);
     addMigration(local.key(), metaRow);
   }
 
@@ -525,7 +527,7 @@ List<MigrationResource> runAll(List<LocalMigrationResource> localVersions) throw
     }
     if (patchLegacyChecksums && !checkStateOnly) {
       // only patch the legacy checksums once
-      initMetaRow.resetChecksum(EARLY_MODE_CHECKSUM, connection, updateChecksumSql);
+      initMetaRow.resetChecksum(EARLY_MODE_CHECKSUM, context.connection(), updateChecksumSql);
     }
     return checkMigrations;
   }

ebean-migration/src/test/java/io/ebean/migration/runner/MigrationTable1Test.java

@@ -44,7 +44,7 @@ public void shutdown() {
 
 
   private MigrationTable migrationTable(Connection conn) {
-    var fc = new FirstCheck(config, conn, platform);
+    var fc = new FirstCheck(config, new DefaultMigrationContext(config, conn), platform);
     return new MigrationTable(fc, false);
   }
 

ebean-migration/src/test/java/io/ebean/migration/runner/MigrationTable2Test.java

@@ -12,7 +12,7 @@ public class MigrationTable2Test {
 
 
   private static MigrationTable migrationTable(MigrationConfig config) {
-    var fc = new FirstCheck(config, null, new MigrationPlatform());
+    var fc = new FirstCheck(config, new DefaultMigrationContext(config, null), new MigrationPlatform());
     return new MigrationTable(fc, false);
   }
 

ebean-migration/src/test/java/io/ebean/migration/runner/MigrationTableAsyncTest.java

@@ -204,7 +204,7 @@ private void runTest(boolean withExisting) throws SQLException, InterruptedExcep
   }
 
   private static MigrationTable migrationTable(MigrationPlatform platform, Connection connection) {
-    var fc = new FirstCheck(config, connection, platform);
+    var fc = new FirstCheck(config, new DefaultMigrationContext(config, connection), platform);
     return new MigrationTable(fc, false);
   }