Merge pull request #16015 from anandshastri1990

* pr/16015:
  Polish "Add failure analyzer for Flyway's bootstrap failure"
  Add failure analyzer for Flyway's bootstrap failure

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/flyway/FlywayAutoConfiguration.java

@@ -16,7 +16,6 @@
 
 package org.springframework.boot.autoconfigure.flyway;
 
-import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashSet;
@@ -63,7 +62,6 @@ import org.springframework.jdbc.support.JdbcUtils;
 import org.springframework.jdbc.support.MetaDataAccessException;
 import org.springframework.orm.jpa.AbstractEntityManagerFactoryBean;
 import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
-import org.springframework.util.Assert;
 import org.springframework.util.CollectionUtils;
 import org.springframework.util.ObjectUtils;
 import org.springframework.util.StringUtils;
@@ -163,14 +161,11 @@ public class FlywayAutoConfiguration {
 		private void checkLocationExists(DataSource dataSource,
 				FlywayProperties properties, ResourceLoader resourceLoader) {
 			if (properties.isCheckLocation()) {
-				String[] locations = new LocationResolver(dataSource)
+				List<String> locations = new LocationResolver(dataSource)
 						.resolveLocations(properties.getLocations());
-				Assert.state(locations.length != 0,
-						"Migration script locations not configured");
-				boolean exists = hasAtLeastOneLocation(resourceLoader, locations);
-				Assert.state(exists, () -> "Cannot find migrations location in: "
-						+ Arrays.asList(locations)
-						+ " (please add migrations or check your Flyway configuration)");
+				if (!hasAtLeastOneLocation(resourceLoader, locations)) {
+					throw new FlywayMigrationScriptMissingException(locations);
+				}
 			}
 		}
 
@@ -178,7 +173,7 @@ public class FlywayAutoConfiguration {
 				FlywayProperties properties) {
 			PropertyMapper map = PropertyMapper.get().alwaysApplyingWhenNonNull();
 			String[] locations = new LocationResolver(configuration.getDataSource())
-					.resolveLocations(properties.getLocations());
+					.resolveLocations(properties.getLocations()).toArray(new String[0]);
 			map.from(locations).to(configuration::locations);
 			map.from(properties.getEncoding()).to(configuration::encoding);
 			map.from(properties.getConnectRetries()).to(configuration::connectRetries);
@@ -255,7 +250,7 @@ public class FlywayAutoConfiguration {
 		}
 
 		private boolean hasAtLeastOneLocation(ResourceLoader resourceLoader,
-				String... locations) {
+				Collection<String> locations) {
 			for (String location : locations) {
 				if (resourceLoader.getResource(normalizePrefix(location)).exists()) {
 					return true;
@@ -385,11 +380,7 @@ public class FlywayAutoConfiguration {
 			this.dataSource = dataSource;
 		}
 
-		public String[] resolveLocations(Collection<String> locations) {
-			return resolveLocations(StringUtils.toStringArray(locations));
-		}
-
-		public String[] resolveLocations(String[] locations) {
+		public List<String> resolveLocations(List<String> locations) {
 			if (usesVendorLocation(locations)) {
 				DatabaseDriver databaseDriver = getDatabaseDriver();
 				return replaceVendorLocations(locations, databaseDriver);
@@ -397,15 +388,15 @@ public class FlywayAutoConfiguration {
 			return locations;
 		}
 
-		private String[] replaceVendorLocations(String[] locations,
+		private List<String> replaceVendorLocations(List<String> locations,
 				DatabaseDriver databaseDriver) {
 			if (databaseDriver == DatabaseDriver.UNKNOWN) {
 				return locations;
 			}
 			String vendor = databaseDriver.getId();
-			return Arrays.stream(locations)
+			return locations.stream()
 					.map((location) -> location.replace(VENDOR_PLACEHOLDER, vendor))
-					.toArray(String[]::new);
+					.collect(Collectors.toList());
 		}
 
 		private DatabaseDriver getDatabaseDriver() {
@@ -419,7 +410,7 @@ public class FlywayAutoConfiguration {
 
 		}
 
-		private boolean usesVendorLocation(String... locations) {
+		private boolean usesVendorLocation(Collection<String> locations) {
 			for (String location : locations) {
 				if (location.contains(VENDOR_PLACEHOLDER)) {
 					return true;

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/flyway/FlywayMigrationScriptMissingException.java

+/*
+ * Copyright 2012-2019 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 org.springframework.boot.autoconfigure.flyway;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Exception thrown when no Flyway migration script is available.
+ *
+ * @author Anand Shastri
+ * @author Stephane Nicoll
+ * @since 2.2.0
+ */
+public class FlywayMigrationScriptMissingException extends RuntimeException {
+
+	private final List<String> locations;
+
+	FlywayMigrationScriptMissingException(List<String> locations) {
+		super(locations.isEmpty() ? "Migration script locations not configured"
+				: "Cannot find migrations location in: " + locations
+						+ " (please add migrations or check your Flyway configuration)");
+		this.locations = new ArrayList<>(locations);
+	}
+
+	public List<String> getLocations() {
+		return this.locations;
+	}
+
+}

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/flyway/FlywayMigrationScriptMissingFailureAnalyzer.java

+/*
+ * Copyright 2012-2019 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 org.springframework.boot.autoconfigure.flyway;
+
+import org.springframework.boot.diagnostics.AbstractFailureAnalyzer;
+import org.springframework.boot.diagnostics.FailureAnalysis;
+
+/**
+ * A {@code FailureAnalyzer} that performs analysis of failures caused by a
+ * {@link FlywayMigrationScriptMissingException}.
+ *
+ * @author Anand Shastri
+ * @author Stephane Nicoll
+ */
+class FlywayMigrationScriptMissingFailureAnalyzer
+		extends AbstractFailureAnalyzer<FlywayMigrationScriptMissingException> {
+
+	@Override
+	protected FailureAnalysis analyze(Throwable rootFailure,
+			FlywayMigrationScriptMissingException cause) {
+		StringBuilder description = new StringBuilder("Flyway failed to initialize: ");
+		if (cause.getLocations().isEmpty()) {
+			return new FailureAnalysis(description
+					.append("no migration scripts location is configured").toString(),
+					"Check your Flyway configuration", cause);
+		}
+		else {
+			description.append(String.format(
+					"none of the following migration scripts locations could be found:%n%n"));
+			cause.getLocations().forEach((location) -> description
+					.append(String.format("\t- %s%n", location)));
+			return new FailureAnalysis(description.toString(),
+					"Review the locations above or check your Flyway configuration",
+					cause);
+		}
+	}
+
+}

spring-boot-project/spring-boot-autoconfigure/src/main/resources/META-INF/spring.factories

@@ -141,6 +141,7 @@ org.springframework.boot.autoconfigure.webservices.client.WebServiceTemplateAuto
 # Failure analyzers
 org.springframework.boot.diagnostics.FailureAnalyzer=\
 org.springframework.boot.autoconfigure.diagnostics.analyzer.NoSuchBeanDefinitionFailureAnalyzer,\
+org.springframework.boot.autoconfigure.flyway.FlywayMigrationScriptMissingFailureAnalyzer,\
 org.springframework.boot.autoconfigure.jdbc.DataSourceBeanCreationFailureAnalyzer,\
 org.springframework.boot.autoconfigure.jdbc.HikariDriverConfigurationFailureAnalyzer,\
 org.springframework.boot.autoconfigure.session.NonUniqueSessionRepositoryFailureAnalyzer

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/flyway/FlywayMigrationScriptMissingFailureAnalyzerTests.java

+/*
+ * Copyright 2012-2019 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 org.springframework.boot.autoconfigure.flyway;
+
+import java.util.Arrays;
+
+import org.junit.Test;
+
+import org.springframework.boot.diagnostics.FailureAnalysis;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link FlywayMigrationScriptMissingFailureAnalyzer}.
+ *
+ * @author Anand Shastri
+ */
+public class FlywayMigrationScriptMissingFailureAnalyzerTests {
+
+	@Test
+	public void analysisForMissingScriptLocation() {
+		FailureAnalysis failureAnalysis = performAnalysis();
+		assertThat(failureAnalysis.getDescription())
+				.contains("no migration scripts location is configured");
+		assertThat(failureAnalysis.getAction())
+				.contains("Check your Flyway configuration");
+	}
+
+	@Test
+	public void analysisForScriptLocationsNotFound() {
+		FailureAnalysis failureAnalysis = performAnalysis("classpath:db/migration");
+		assertThat(failureAnalysis.getDescription()).contains(
+				"none of the following migration scripts locations could be found")
+				.contains("classpath:db/migration");
+		assertThat(failureAnalysis.getAction()).contains(
+				"Review the locations above or check your Flyway configuration");
+	}
+
+	private FailureAnalysis performAnalysis(String... locations) {
+		FlywayMigrationScriptMissingException exception = new FlywayMigrationScriptMissingException(
+				Arrays.asList(locations));
+		return new FlywayMigrationScriptMissingFailureAnalyzer().analyze(exception);
+	}
+
+}