Automatically enable earlyChecksumMode when using index file with pre-computed checksums and automatically patch legacy checksums for this case

Author: rob-bygrave

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

@@ -48,6 +48,8 @@ boolean readInitResources() {
    */
   boolean readResources() {
     if (readFromIndex()) {
+      // automatically enable earlyChecksumMode when using index file with pre-computed checksums
+      migrationConfig.setEarlyChecksumMode(true);
       return true;
     }
     return readResourcesForPath(migrationConfig.getMigrationPath());
@@ -86,7 +88,7 @@ private boolean loadFromIndexFile(URL idx, String base) {
           if (pair.length == 2) {
             final var checksum = Integer.parseInt(pair[0]);
             final var location = pair[1].trim();
-            final String substring = location.substring(0, location.length() - 4);
+            final var substring = location.substring(0, location.length() - 4);
             final var version = MigrationVersion.parse(substring);
             final var url = resource(base + location);
             versions.add(new LocalUriMigrationResource(version, location, url, checksum));

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

@@ -23,6 +23,7 @@ final class MigrationTable {
   private static final String INIT_VER_0 = "0";
   private static final int LEGACY_MODE_CHECKSUM = 0;
   private static final int EARLY_MODE_CHECKSUM = 1;
+  private static final int AUTO_PATCH_CHECKSUM = -1;
 
   private final Connection connection;
   private final boolean checkStateOnly;
@@ -305,6 +306,7 @@ private boolean runMigration(LocalMigrationResource local, MigrationMetaRow exis
     int checksum2 = 0;
     if (local instanceof LocalUriMigrationResource) {
       checksum = ((LocalUriMigrationResource)local).checksum();
+      checksum2 = patchLegacyChecksums ? AUTO_PATCH_CHECKSUM : 0;
       script = convertScript(local.content());
     } else if (local instanceof LocalDdlMigrationResource) {
       final String content = local.content();
@@ -349,7 +351,7 @@ boolean skipMigration(int checksum, int checksum2, LocalMigrationResource local,
       log.log(TRACE, "skip unchanged migration {0}", local.location());
       return true;
 
-    } else if (patchLegacyChecksums && existing.checksum() == checksum2) {
+    } else if (patchLegacyChecksums && (existing.checksum() == checksum2 || checksum2 == AUTO_PATCH_CHECKSUM)) {
       if (!checkStateOnly) {
         log.log(INFO, "Patch migration, set early mode checksum on {0}", local.location());
         existing.resetChecksum(checksum, connection, updateChecksumSql);

ebean-migration/src/test/java/io/ebean/migration/MigrationRunner_FastCheckTest.java

@@ -1,7 +1,15 @@
 package io.ebean.migration;
 
+import io.ebean.datasource.DataSourceConfig;
+import io.ebean.datasource.DataSourceFactory;
+import io.ebean.datasource.DataSourcePool;
 import org.junit.jupiter.api.Test;
 
+import java.util.List;
+import java.util.Map;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
 public class MigrationRunner_FastCheckTest {
 
   private MigrationConfig createMigrationConfig() {
@@ -39,4 +47,54 @@ public void run_when() {
     runner.run();
   }
 
+  @Test
+  public void autoEnableEarlyMode_when_indexFileAddedToExistingMigrations() {
+
+    String url = "jdbc:h2:mem:autoEnableEarlyMode";
+    DataSourceConfig dataSourceConfig = new DataSourceConfig()
+      .setUrl(url)
+      .setUsername("sa")
+      .setPassword("");
+
+    DataSourcePool dataSource = DataSourceFactory.create("test", dataSourceConfig);
+
+    MigrationConfig config = new MigrationConfig();
+    config.setPlatform("h2");
+    config.setRunPlaceholderMap(Map.of("my_table_name", "bar"));
+
+    // initial traditional migration
+    config.setMigrationPath("indexB_0");
+    MigrationRunner runner = new MigrationRunner(config);
+    runner.run(dataSource);
+
+    assertThat(config.isEarlyChecksumMode()).isFalse();
+
+    // add an index file now, expect automatically go to early mode + patch checksums
+    config.setMigrationPath("indexB_1");
+    new MigrationRunner(config).run(dataSource);
+    assertThat(config.isEarlyChecksumMode()).isTrue();
+
+    // early mode via <init> row + add an extra migration
+    config.setMigrationPath("indexB_2");
+    new MigrationRunner(config).run(dataSource);
+
+    dataSource.shutdown();
+  }
+
+  @Test
+  public void autoEnableEarlyMode() {
+
+    MigrationConfig config = createMigrationConfig();
+
+    config.setPlatform("h2");
+    config.setMigrationPath("indexB_1");
+    config.setDbUrl("jdbc:h2:mem:autoEnableEarlyMode_simple");
+    config.setRunPlaceholderMap(Map.of("my_table_name", "bar"));
+
+    MigrationRunner runner = new MigrationRunner(config);
+    runner.run();
+
+    assertThat(config.isEarlyChecksumMode()).isTrue();
+  }
+
 }

ebean-migration/src/test/resources/indexB_0/1.0__initial.sql

@@ -0,0 +1,6 @@
+-- apply changes
+create table ${my_table_name} (
+  id                            integer generated by default as identity not null,
+  name                          varchar(255),
+  constraint pk_${my_table_name} primary key (id)
+);

ebean-migration/src/test/resources/indexB_0/1.1.sql

@@ -0,0 +1 @@
+insert into ${my_table_name} (name) values ('hi');

ebean-migration/src/test/resources/indexB_0/1.2.sql

@@ -0,0 +1 @@
+create table foo (acol varchar(10));

ebean-migration/src/test/resources/indexB_1/1.0__initial.sql

@@ -0,0 +1,6 @@
+-- apply changes
+create table ${my_table_name} (
+  id                            integer generated by default as identity not null,
+  name                          varchar(255),
+  constraint pk_${my_table_name} primary key (id)
+);

ebean-migration/src/test/resources/indexB_1/1.1.sql

@@ -0,0 +1 @@
+insert into ${my_table_name} (name) values ('hi');

ebean-migration/src/test/resources/indexB_1/1.2.sql

@@ -0,0 +1 @@
+create table foo (acol varchar(10));

ebean-migration/src/test/resources/indexB_1/idx_h2.migrations

@@ -0,0 +1,4 @@
+845768926,      1.0__initial.sql
+19858255,       1.1.sql
+513154593,      1.2.sql
+