Make sure binder properly resolve resources

This commit makes sure that `@ConfigurationProperties` binding resolves
resources properly. In particular, any `ProtocolResolver` registered on
the `ApplicationContext` is now honoured.

Closes gh-11569

spring-boot/src/main/java/org/springframework/boot/bind/PropertiesConfigurationFactory.java

 /*
- * 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.
@@ -31,6 +31,9 @@ import org.springframework.beans.BeanUtils;
 import org.springframework.beans.PropertyValues;
 import org.springframework.beans.factory.FactoryBean;
 import org.springframework.beans.factory.InitializingBean;
+import org.springframework.beans.support.ResourceEditorRegistrar;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.ApplicationContextAware;
 import org.springframework.context.MessageSource;
 import org.springframework.context.MessageSourceAware;
 import org.springframework.core.convert.ConversionService;
@@ -52,7 +55,7 @@ import org.springframework.validation.Validator;
  * @author Dave Syer
  */
 public class PropertiesConfigurationFactory<T>
-		implements FactoryBean<T>, MessageSourceAware, InitializingBean {
+		implements FactoryBean<T>, ApplicationContextAware, MessageSourceAware, InitializingBean {
 
 	private static final char[] EXACT_DELIMITERS = { '_', '.', '[' };
 
@@ -73,6 +76,8 @@ public class PropertiesConfigurationFactory<T>
 
 	private Validator validator;
 
+	private ApplicationContext applicationContext;
+
 	private MessageSource messageSource;
 
 	private boolean hasBeenBound = false;
@@ -149,6 +154,11 @@ public class PropertiesConfigurationFactory<T>
 		this.targetName = targetName;
 	}
 
+	@Override
+	public void setApplicationContext(ApplicationContext applicationContext) {
+		this.applicationContext = applicationContext;
+	}
+
 	/**
 	 * Set the message source.
 	 * @param messageSource the message source
@@ -265,6 +275,11 @@ public class PropertiesConfigurationFactory<T>
 		dataBinder.setIgnoreInvalidFields(this.ignoreInvalidFields);
 		dataBinder.setIgnoreUnknownFields(this.ignoreUnknownFields);
 		customizeBinder(dataBinder);
+		if (this.applicationContext != null) {
+			ResourceEditorRegistrar resourceEditorRegistrar = new ResourceEditorRegistrar(
+					this.applicationContext, this.applicationContext.getEnvironment());
+			resourceEditorRegistrar.registerCustomEditors(dataBinder);
+		}
 		Iterable<String> relaxedTargetNames = getRelaxedTargetNames();
 		Set<String> names = getNames(relaxedTargetNames);
 		PropertyValues propertyValues = getPropertySourcesPropertyValues(names,

spring-boot/src/main/java/org/springframework/boot/context/properties/ConfigurationPropertiesBindingPostProcessor.java

 /*
- * 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.
@@ -312,6 +312,7 @@ public class ConfigurationPropertiesBindingPostProcessor implements BeanPostProc
 		PropertiesConfigurationFactory<Object> factory = new PropertiesConfigurationFactory<Object>(
 				target);
 		factory.setPropertySources(this.propertySources);
+		factory.setApplicationContext(this.applicationContext);
 		factory.setValidator(determineValidator(bean));
 		// If no explicit conversion service is provided we add one so that (at least)
 		// comma-separated arrays of convertibles can be bound automatically

spring-boot/src/test/java/org/springframework/boot/context/properties/ConfigurationPropertiesBindingPostProcessorTests.java

 /*
- * 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.
@@ -40,6 +40,10 @@ import org.springframework.context.annotation.AnnotationConfigApplicationContext
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.support.PropertySourcesPlaceholderConfigurer;
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.core.io.ProtocolResolver;
+import org.springframework.core.io.Resource;
+import org.springframework.core.io.ResourceLoader;
 import org.springframework.mock.env.MockEnvironment;
 import org.springframework.test.context.support.TestPropertySourceUtils;
 import org.springframework.test.util.ReflectionTestUtils;
@@ -52,6 +56,12 @@ import org.springframework.validation.beanvalidation.LocalValidatorFactoryBean;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.Assert.fail;
+import static org.mockito.BDDMockito.given;
+import static org.mockito.Matchers.any;
+import static org.mockito.Matchers.anyString;
+import static org.mockito.Matchers.eq;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
 
 /**
  * Tests for {@link ConfigurationPropertiesBindingPostProcessor}.
@@ -366,6 +376,38 @@ public class ConfigurationPropertiesBindingPostProcessorTests {
 		}
 	}
 
+	@Test
+	public void customProtocolResolverIsInvoked() {
+		this.context = new AnnotationConfigApplicationContext();
+		TestPropertySourceUtils.addInlinedPropertiesToEnvironment(this.context,
+				"test.resource=application.properties");
+		ProtocolResolver protocolResolver = mock(ProtocolResolver.class);
+		given(protocolResolver.resolve(anyString(), any(ResourceLoader.class)))
+				.willReturn(null);
+		this.context.addProtocolResolver(protocolResolver);
+		this.context.register(PropertiesWithResource.class);
+		this.context.refresh();
+		verify(protocolResolver).resolve(eq("application.properties"),
+				any(ResourceLoader.class));
+	}
+
+	@Test
+	public void customProtocolResolver() {
+		this.context = new AnnotationConfigApplicationContext();
+		TestPropertySourceUtils.addInlinedPropertiesToEnvironment(this.context,
+				"test.resource=test:/application.properties");
+		this.context.addProtocolResolver(new TestProtocolResolver());
+		this.context.register(PropertiesWithResource.class);
+		this.context.refresh();
+		Resource resource = this.context.getBean(PropertiesWithResource.class)
+				.getResource();
+		assertThat(resource).isNotNull();
+		assertThat(resource).isInstanceOf(ClassPathResource.class);
+		assertThat(resource.exists()).isTrue();
+		assertThat(((ClassPathResource) resource).getPath())
+				.isEqualTo("application.properties");
+	}
+
 	@Configuration
 	@EnableConfigurationProperties
 	public static class TestConfigurationWithValidatingSetter {
@@ -819,4 +861,35 @@ public class ConfigurationPropertiesBindingPostProcessorTests {
 
 	}
 
+	@Configuration
+	@EnableConfigurationProperties
+	@ConfigurationProperties(prefix = "test")
+	public static class PropertiesWithResource {
+
+		private Resource resource;
+
+		public Resource getResource() {
+			return this.resource;
+		}
+
+		public void setResource(Resource resource) {
+			this.resource = resource;
+		}
+
+	}
+
+	private static class TestProtocolResolver implements ProtocolResolver {
+
+		public static final String PREFIX = "test:/";
+
+		@Override
+		public Resource resolve(String location, ResourceLoader resourceLoader) {
+			if (location.startsWith(PREFIX)) {
+				String path = location.substring(PREFIX.length(), location.length());
+				return new ClassPathResource(path);
+			}
+			return null;
+		}
+	}
+
 }