#22 fix missing optional dependencies

Author: tomix26

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

@@ -57,6 +57,7 @@
 import org.springframework.test.context.ContextCustomizerFactory;
 import org.springframework.test.context.MergedContextConfiguration;
 import org.springframework.util.Assert;
+import org.springframework.util.ClassUtils;
 import org.springframework.util.ObjectUtils;
 
 import javax.sql.DataSource;
@@ -192,10 +193,19 @@ public void postProcessBeanDefinitionRegistry(BeanDefinitionRegistry registry) t
             ConfigurableListableBeanFactory beanFactory = (ConfigurableListableBeanFactory) registry;
 
             registerBeanIfMissing(registry, "defaultDatabaseProvider", PrefetchingDatabaseProvider.class);
-            registerBeanIfMissing(registry, "dockerPostgresProvider", DockerPostgresDatabaseProvider.class);
-            registerBeanIfMissing(registry, "zonkyPostgresProvider", ZonkyPostgresDatabaseProvider.class);
-            registerBeanIfMissing(registry, "openTablePostgresProvider", OpenTablePostgresDatabaseProvider.class);
-            registerBeanIfMissing(registry, "yandexPostgresProvider", YandexPostgresDatabaseProvider.class);
+
+            if (ClassUtils.isPresent("org.testcontainers.containers.PostgreSQLContainer", null)) {
+                registerBeanIfMissing(registry, "dockerPostgresProvider", DockerPostgresDatabaseProvider.class);
+            }
+            if (ClassUtils.isPresent("io.zonky.test.db.postgres.embedded.EmbeddedPostgres", null)) {
+                registerBeanIfMissing(registry, "zonkyPostgresProvider", ZonkyPostgresDatabaseProvider.class);
+            }
+            if (ClassUtils.isPresent("com.opentable.db.postgres.embedded.EmbeddedPostgres", null)) {
+                registerBeanIfMissing(registry, "openTablePostgresProvider", OpenTablePostgresDatabaseProvider.class);
+            }
+            if (ClassUtils.isPresent("ru.yandex.qatools.embed.postgresql.EmbeddedPostgres", null)) {
+                registerBeanIfMissing(registry, "yandexPostgresProvider", YandexPostgresDatabaseProvider.class);
+            }
 
             for (AutoConfigureEmbeddedDatabase databaseAnnotation : databaseAnnotations) {
                 DatabaseDescriptor databaseDescriptor = resolveDatabaseDescriptor(environment, databaseAnnotation);

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

@@ -0,0 +1,35 @@
+/*
+ * 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.provider;
+
+public class MissingDatabaseProviderException extends IllegalStateException {
+
+    private final DatabaseDescriptor descriptor;
+
+    public MissingDatabaseProviderException(DatabaseDescriptor descriptor) {
+        this.descriptor = descriptor;
+    }
+
+    public DatabaseDescriptor getDescriptor() {
+        return descriptor;
+    }
+
+    @Override
+    public String getMessage() {
+        return String.format("Missing database provider for descriptor: %s", descriptor);
+    }
+}

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

@@ -0,0 +1,36 @@
+/*
+ * 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.provider;
+
+public class MissingProviderDependencyException extends MissingDatabaseProviderException {
+
+    public MissingProviderDependencyException(DatabaseDescriptor descriptor) {
+        super(descriptor);
+    }
+
+    @Override
+    public String getMessage() {
+        ProviderType providerType = getDescriptor().getProviderType();
+        String dependencyInfo = providerType.getDependencyInfo();
+
+        if (dependencyInfo != null) {
+            return String.format("You must add the following Maven dependency: '%s'", dependencyInfo);
+        } else {
+            return String.format("You must add a Maven dependency for '%s' provider", providerType);
+        }
+    }
+}

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

@@ -19,29 +19,42 @@
 import org.springframework.util.Assert;
 
 import java.util.Objects;
+import java.util.stream.Stream;
 
 public final class ProviderType {
 
-    public static final ProviderType DOCKER = ProviderType.valueOf("docker");
-    public static final ProviderType ZONKY = ProviderType.valueOf("zonky");
-    public static final ProviderType OPENTABLE = ProviderType.valueOf("opentable");
-    public static final ProviderType YANDEX = ProviderType.valueOf("yandex");
+    public static final ProviderType DOCKER = new ProviderType("docker", "org.testcontainers:postgresql");
+    public static final ProviderType ZONKY = new ProviderType("zonky", "io.zonky.test:embedded-postgres");
+    public static final ProviderType OPENTABLE = new ProviderType("opentable", "com.opentable.components:otj-pg-embedded");
+    public static final ProviderType YANDEX = new ProviderType("yandex", "ru.yandex.qatools.embed:postgresql-embedded");
 
     private final String name;
+    private final String dependency;
 
     public static ProviderType valueOf(String name) {
         Assert.notNull(name, "Provider name must not be null");
-        return new ProviderType(name.toLowerCase());
+        return Stream.of(DOCKER, ZONKY, OPENTABLE, YANDEX)
+                .filter(type -> type.name().equals(name.toLowerCase()))
+                .findFirst().orElse(new ProviderType(name.toLowerCase()));
     }
 
     private ProviderType(String name) {
+        this(name, null);
+    }
+
+    private ProviderType(String name, String dependency) {
         this.name = name;
+        this.dependency = dependency;
     }
 
     public String name() {
         return name;
     }
 
+    String getDependencyInfo() {
+        return dependency;
+    }
+
     @Override
     public boolean equals(Object o) {
         if (this == o) return true;

embedded-database-spring-test/src/main/java/io/zonky/test/db/provider/impl/DockerPostgresDatabaseProvider.java

@@ -60,12 +60,7 @@ public class DockerPostgresDatabaseProvider implements DatabaseProvider {
     private static final LoadingCache<DatabaseConfig, DatabaseInstance> databases = CacheBuilder.newBuilder()
             .build(new CacheLoader<DatabaseConfig, DatabaseInstance>() {
                 public DatabaseInstance load(DatabaseConfig config) {
-                    try {
-                        return new DatabaseInstance(config);
-                    } catch (NoClassDefFoundError e) {
-                        logger.error("\n\nHINT: You may have to add org.testcontainers:postgresql dependency!!!\n");
-                        throw e;
-                    }
+                    return new DatabaseInstance(config);
                 }
             });
 

embedded-database-spring-test/src/main/java/io/zonky/test/db/provider/impl/OpenTablePostgresDatabaseProvider.java

@@ -60,12 +60,7 @@ public class OpenTablePostgresDatabaseProvider implements DatabaseProvider {
     private static final LoadingCache<DatabaseConfig, DatabaseInstance> databases = CacheBuilder.newBuilder()
             .build(new CacheLoader<DatabaseConfig, DatabaseInstance>() {
                 public DatabaseInstance load(DatabaseConfig config) throws IOException {
-                    try {
-                        return new DatabaseInstance(config);
-                    } catch (NoClassDefFoundError e) {
-                        logger.error("\n\nHINT: You may have to add com.opentable.components:otj-pg-embedded dependency!!!\n");
-                        throw e;
-                    }
+                    return new DatabaseInstance(config);
                 }
             });
 

embedded-database-spring-test/src/main/java/io/zonky/test/db/provider/impl/PrefetchingDatabaseProvider.java

@@ -23,6 +23,8 @@
 import io.zonky.test.db.provider.DatabasePreparer;
 import io.zonky.test.db.provider.DatabaseProvider;
 import io.zonky.test.db.provider.GenericDatabaseProvider;
+import io.zonky.test.db.provider.MissingDatabaseProviderException;
+import io.zonky.test.db.provider.MissingProviderDependencyException;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.ObjectProvider;
@@ -92,7 +94,7 @@ public DataSource getDatabase(DatabasePreparer preparer, DatabaseDescriptor desc
 
         DatabaseProvider provider = databaseProviders.get(descriptor);
         if (provider == null) {
-            throw new IllegalStateException(String.format("Missing database provider for descriptor: %s", descriptor));
+            throw missingDatabaseProviderException(descriptor);
         }
 
         PipelineKey key = new PipelineKey(preparer, descriptor, provider);
@@ -126,6 +128,17 @@ public DataSource getDatabase(DatabasePreparer preparer, DatabaseDescriptor desc
         return dataSource;
     }
 
+    protected MissingDatabaseProviderException missingDatabaseProviderException(DatabaseDescriptor descriptor) {
+        boolean isProviderPresent = databaseProviders.keySet().stream()
+                .map(DatabaseDescriptor::getProviderType)
+                .anyMatch(p -> p.equals(descriptor.getProviderType()));
+        if (isProviderPresent) {
+            return new MissingDatabaseProviderException(descriptor);
+        } else {
+            return new MissingProviderDependencyException(descriptor);
+        }
+    }
+
     private ListenableFutureTask<DataSource> prepareDatabase(PipelineKey key, int priority) {
         PrefetchingTask task = new PrefetchingTask(key.provider, key.preparer, priority);
         DatabasePipeline pipeline = pipelines.get(key);

embedded-database-spring-test/src/main/java/io/zonky/test/db/provider/impl/YandexPostgresDatabaseProvider.java

@@ -64,12 +64,7 @@ public class YandexPostgresDatabaseProvider implements DatabaseProvider {
     private static final LoadingCache<DatabaseConfig, DatabaseInstance> databases = CacheBuilder.newBuilder()
             .build(new CacheLoader<DatabaseConfig, DatabaseInstance>() {
                 public DatabaseInstance load(DatabaseConfig config) throws IOException {
-                    try {
-                        return new DatabaseInstance(config);
-                    } catch (NoClassDefFoundError e) {
-                        logger.error("\n\nHINT: You may have to add ru.yandex.qatools.embed:postgresql-embedded dependency!!!\n");
-                        throw e;
-                    }
+                    return new DatabaseInstance(config);
                 }
             });
 

embedded-database-spring-test/src/main/java/io/zonky/test/db/provider/impl/ZonkyPostgresDatabaseProvider.java

@@ -60,12 +60,7 @@ public class ZonkyPostgresDatabaseProvider implements DatabaseProvider {
     private static final LoadingCache<DatabaseConfig, DatabaseInstance> databases = CacheBuilder.newBuilder()
             .build(new CacheLoader<DatabaseConfig, DatabaseInstance>() {
                 public DatabaseInstance load(DatabaseConfig config) throws IOException {
-                    try {
-                        return new DatabaseInstance(config);
-                    } catch (NoClassDefFoundError e) {
-                        logger.error("\n\nHINT: You may have to add io.zonky.test:embedded-postgres dependency!!!\n");
-                        throw e;
-                    }
+                    return new DatabaseInstance(config);
                 }
             });