Fix Flyway filesystem prefix location check

Co-authored-by: Andy Bell <andyrbell@gmail.com>

Closes gh-13863

Author: snicoll

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

@@ -117,13 +117,17 @@ public void checkLocationExists() {
 
 		private boolean hasAtLeastOneLocation() {
 			for (String location : this.properties.getLocations()) {
-				if (this.resourceLoader.getResource(location).exists()) {
+				if (this.resourceLoader.getResource(normalizePrefix(location)).exists()) {
 					return true;
 				}
 			}
 			return false;
 		}
 
+		private String normalizePrefix(String location) {
+			return location.replace("filesystem:", "file:");
+		}
+
 		@Bean
 		@ConfigurationProperties(prefix = "flyway")
 		public Flyway flyway() {

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2018 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.
@@ -153,7 +153,7 @@ public void overrideSchemas() throws Exception {
 	@Test
 	public void changeLogDoesNotExist() throws Exception {
 		EnvironmentTestUtils.addEnvironment(this.context,
-				"flyway.locations:file:no-such-dir");
+				"flyway.locations:filesystem:no-such-dir");
 		this.thrown.expect(BeanCreationException.class);
 		registerAndRefresh(EmbeddedDataSourceConfiguration.class,
 				FlywayAutoConfiguration.class,
@@ -192,6 +192,16 @@ public void checkLocationsAllExistWithImplicitClasspathPrefix() throws Exception
 				PropertyPlaceholderAutoConfiguration.class);
 	}
 
+	@Test
+	public void checkLocationsAllExistWithImplicitFilesystemPrefix() {
+		EnvironmentTestUtils.addEnvironment(this.context,
+				"flyway.locations:filesystem:src/test/resources/db/migration",
+				"flyway.check-location:true");
+		registerAndRefresh(EmbeddedDataSourceConfiguration.class,
+				FlywayAutoConfiguration.class,
+				PropertyPlaceholderAutoConfiguration.class);
+	}
+
 	@Test
 	public void customFlywayMigrationStrategy() throws Exception {
 		registerAndRefresh(EmbeddedDataSourceConfiguration.class,

spring-boot-docs/src/main/asciidoc/howto.adoc

@@ -2246,8 +2246,18 @@ To automatically run Flyway database migrations on startup, add the
 
 The migrations are scripts in the form `V<VERSION>__<NAME>.sql` (with `<VERSION>` an
 underscore-separated version, e.g. '`1`' or '`2_1`'). By default they live in a folder
-`classpath:db/migration` but you can modify that using `flyway.locations`. You can also
-add a special `{vendor}` placeholder to use vendor-specific scripts. Assume the following:
+`classpath:db/migration` but you can modify that using `flyway.locations`. This is a
+comma-separated list of one or more `classpath:` or `filesystem:` locations. For example,
+the following configuration would search for scripts in both the default classpath
+location and the `/opt/migration` directory:
+
+[source,properties,indent=0]
+----
+	spring.flyway.locations=classpath:db/migration,filesystem:/opt/migration
+----
+
+You can also add a special `{vendor}` placeholder to use vendor-specific scripts. Assume
+the following:
 
 [source,properties,indent=0]
 ----