Merge pull request #38 from zonkyio/multiple-datasources

#33 Support repeatable @AutoConfigureEmbeddedDatabase annotations

Author: tomix26

README.md

@@ -71,6 +71,31 @@ public class EmptyDatabaseIntegrationTest {
 }
 ```
 
+### Creating multiple independent databases
+
+Because the `@AutoConfigureEmbeddedDatabase` is a repeatable annotation, you can annotate a test class with multiple annotations to create multiple independent databases.
+Each of them may have completely different configuration parameters, including the database provider as demonstrated in the example below.
+
+Note that if multiple annotations on a single class are applied, some optimization techniques can not be used and database initialization may be slower.
+
+```java
+@RunWith(SpringRunner.class)
+@AutoConfigureEmbeddedDatabase(beanName = "dataSource1")
+@AutoConfigureEmbeddedDatabase(beanName = "dataSource2")
+@AutoConfigureEmbeddedDatabase(beanName = "dataSource3", provider = DOCKER)
+public class MultipleDatabasesIntegrationTest {
+    
+    @Autowired
+    private DataSource dataSource1;
+    @Autowired
+    private DataSource dataSource2;
+    @Autowired
+    private DataSource dataSource3;
+    
+    // class body...
+}
+```
+
 ### Using `@FlywayTest` annotation on a test class
 
 The library supports the use of `@FlywayTest` annotation. If you use it, the embedded database will be automatically initialized and cleaned by Flyway database migration tool. If you don't specify any custom migration locations the default path `db/migration` will be applied.

embedded-database-spring-test/src/main/java/io/zonky/test/db/AutoConfigureEmbeddedDatabase.java

@@ -20,13 +20,16 @@
 import java.lang.annotation.Documented;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Inherited;
+import java.lang.annotation.Repeatable;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
 /**
  * Annotation that can be applied to a test class to configure an embedded database to use
  * instead of any application defined {@link DataSource}.
+ * <p>
+ * This annotation may be used as a <em>meta-annotation</em> to create custom <em>composed annotations</em>.
  *
  * @see io.zonky.test.db.postgres.EmbeddedPostgresContextCustomizerFactory
  * @see io.zonky.test.db.flyway.OptimizedFlywayTestExecutionListener
@@ -35,6 +38,7 @@
 @Inherited
 @Target(ElementType.TYPE)
 @Retention(RetentionPolicy.RUNTIME)
+@Repeatable(AutoConfigureEmbeddedDatabases.class)
 public @interface AutoConfigureEmbeddedDatabase {
 
     /**

embedded-database-spring-test/src/main/java/io/zonky/test/db/AutoConfigureEmbeddedDatabases.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.zonky.test.db;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Inherited;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Container annotation that aggregates several {@link AutoConfigureEmbeddedDatabase} annotations.
+ * <p>
+ * Can be used natively, declaring several nested {@link AutoConfigureEmbeddedDatabase} annotations.
+ * Can also be used in conjunction with Java 8's support for <em>repeatable annotations</em>,
+ * where {@link AutoConfigureEmbeddedDatabase} can simply be declared several times on the same
+ * {@linkplain ElementType#TYPE type}, implicitly generating this container annotation.
+ * <p>
+ * This annotation may be used as a <em>meta-annotation</em> to create custom <em>composed annotations</em>.
+ *
+ * @see AutoConfigureEmbeddedDatabase
+ */
+@Documented
+@Inherited
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.RUNTIME)
+public @interface AutoConfigureEmbeddedDatabases {
+
+    AutoConfigureEmbeddedDatabase[] value();
+
+}

embedded-database-spring-test/src/main/java/io/zonky/test/db/flyway/DefaultFlywayDataSourceContext.java

@@ -18,9 +18,7 @@
 
 import io.zonky.test.db.provider.DatabaseDescriptor;
 import io.zonky.test.db.provider.DatabasePreparer;
-import io.zonky.test.db.provider.DatabaseType;
 import io.zonky.test.db.provider.GenericDatabaseProvider;
-import io.zonky.test.db.provider.ProviderType;
 import org.apache.commons.lang3.exception.ExceptionUtils;
 import org.flywaydb.core.Flyway;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -63,6 +61,8 @@ public class DefaultFlywayDataSourceContext implements FlywayDataSourceContext {
     @Autowired
     protected GenericDatabaseProvider databaseProvider;
 
+    protected DatabaseDescriptor databaseDescriptor;
+
     protected int maxAttempts = DEFAULT_MAX_RETRY_ATTEMPTS;
 
     protected TaskExecutor bootstrapExecutor;
@@ -98,17 +98,20 @@ public void releaseTarget(Object target) {
         // nothing to do
     }
 
+    @Override
+    public void setDescriptor(DatabaseDescriptor descriptor) {
+        this.databaseDescriptor = descriptor;
+    }
+
     @Override
     public synchronized ListenableFuture<DataSource> reload(Flyway flyway) {
         Executor executor = bootstrapExecutor != null ? bootstrapExecutor : Runnable::run;
 
         CompletableFuture<DataSource> reloadFuture = dataSourceFuture.thenApplyAsync(x -> {
             for (int current = 1; current <= maxAttempts; current++) {
                 try {
-                    String providerName = environment.getProperty("embedded-database.provider", ProviderType.ZONKY.toString());
-                    FlywayDatabasePreparer preparer = new FlywayDatabasePreparer(flyway);
-                    DatabaseDescriptor descriptor = new DatabaseDescriptor(DatabaseType.POSTGRES, ProviderType.valueOf(providerName));
-                    return databaseProvider.getDatabase(preparer, descriptor);
+                    FlywayDatabasePreparer databasePreparer = new FlywayDatabasePreparer(flyway);
+                    return databaseProvider.getDatabase(databasePreparer, databaseDescriptor);
                 } catch (Exception e) {
                     if (ExceptionUtils.indexOfType(e, IOException.class) == -1 || current == maxAttempts) {
                         throw new CompletionException(e);

embedded-database-spring-test/src/main/java/io/zonky/test/db/flyway/FlywayDataSourceContext.java

@@ -16,6 +16,7 @@
 
 package io.zonky.test.db.flyway;
 
+import io.zonky.test.db.provider.DatabaseDescriptor;
 import org.flywaydb.core.Flyway;
 import org.springframework.aop.TargetSource;
 import org.springframework.util.concurrent.ListenableFuture;
@@ -30,4 +31,6 @@ public interface FlywayDataSourceContext extends TargetSource {
 
     ListenableFuture<DataSource> reload(Flyway flyway);
 
+    void setDescriptor(DatabaseDescriptor descriptor);
+
 }