Improve ConfigData processing code

Refactor `ConfigData` processing code to make it less awkward to
follow.

Prior to this commit the `ConfigDataLocationResolver` would take a
String location and return a `ConfigDataLocation` instance. This was
a little confusing since sometimes we would refer to `location` as the
String value, and sometimes it would be the typed instance. We also
had nowhere sensible to put the `optional:` prefix logic and we needed
to pass a `boolean` parameter to a number of methods. The recently
introduced `Orgin` support also didn't have a good home.

To solve this, `ConfigDataLocation` has been renamed to
`ConfigDataResource`. This frees up `ConfigDataLocation` to be used
as a richer `location` type that holds the String value, the `Orgin`
and provides a home for the `optional:` logic.

This commit also cleans up a few other areas of the code, including
renaming `ResourceConfigData...` to `StandardConfigData...`. It also
introduces a new exception hierarchy for `ConfigDataNotFoundExceptions`.

Closes gh-23711

Author: philwebb

Diff for: spring-boot-project/spring-boot-docs/src/docs/asciidoc/spring-boot-features.adoc

@@ -663,7 +663,7 @@ You can use this prefix with the `spring.config.location` and `spring.config.add
 
 For example, a `spring.config.import` value of `optional:file:./myconfig.properties` allows your application to start, even if the `myconfig.properties` file is missing.
 
-If you want to ignore all `ConfigDataLocationNotFoundExceptions` and always continue to start your application, you can use the `spring.config.on-location-not-found` property.
+If you want to ignore all `ConfigDataLocationNotFoundExceptions` and always continue to start your application, you can use the `spring.config.on-not-found` property.
 Set the value to `ignore` using `SpringApplication.setDefaultProperties(...)` or with a system/environment variable.
 
 

Diff for: spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/config/ConfigData.java

@@ -29,9 +29,9 @@
 import org.springframework.util.Assert;
 
 /**
- * Configuration data that has been loaded from an external {@link ConfigDataLocation
- * location} and may ultimately contribute {@link PropertySource property sources} to
- * Spring's {@link Environment}.
+ * Configuration data that has been loaded from a {@link ConfigDataResource} and may
+ * ultimately contribute {@link PropertySource property sources} to Spring's
+ * {@link Environment}.
  *
  * @author Phillip Webb
  * @author Madhura Bhave

Diff for: spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/config/ConfigDataEnvironment.java

@@ -48,10 +48,10 @@
  * Wrapper around a {@link ConfigurableEnvironment} that can be used to import and apply
  * {@link ConfigData}. Configures the initial set of
  * {@link ConfigDataEnvironmentContributors} by wrapping property sources from the Spring
- * {@link Environment} and adding the initial set of imports.
+ * {@link Environment} and adding the initial set of locations.
  * <p>
- * The initial imports can be influenced via the {@link #LOCATION_PROPERTY},
- * {@value #ADDITIONAL_LOCATION_PROPERTY} and {@value #IMPORT_PROPERTY} properties. If not
+ * The initial locations can be influenced via the {@link #LOCATION_PROPERTY},
+ * {@value #ADDITIONAL_LOCATION_PROPERTY} and {@value #IMPORT_PROPERTY} properties. If no
  * explicit properties are set, the {@link #DEFAULT_SEARCH_LOCATIONS} will be used.
  *
  * @author Phillip Webb
@@ -76,28 +76,41 @@ class ConfigDataEnvironment {
 
 	/**
 	 * Property used to determine what action to take when a
-	 * {@code ConfigDataLocationNotFoundException} is thrown.
-	 * @see ConfigDataLocationNotFoundAction
+	 * {@code ConfigDataNotFoundAction} is thrown.
+	 * @see ConfigDataNotFoundAction
 	 */
-	static final String ON_LOCATION_NOT_FOUND_PROPERTY = "spring.config.on-location-not-found";
+	static final String ON_NOT_FOUND_PROPERTY = "spring.config.on-not-found";
 
 	/**
 	 * Default search locations used if not {@link #LOCATION_PROPERTY} is found.
 	 */
-	static final String[] DEFAULT_SEARCH_LOCATIONS = { "optional:classpath:/", "optional:classpath:/config/",
-			"optional:file:./", "optional:file:./config/*/", "optional:file:./config/" };
-
-	private static final String[] EMPTY_LOCATIONS = new String[0];
+	static final ConfigDataLocation[] DEFAULT_SEARCH_LOCATIONS;
+	static {
+		List<ConfigDataLocation> locations = new ArrayList<>();
+		locations.add(ConfigDataLocation.of("optional:classpath:/"));
+		locations.add(ConfigDataLocation.of("optional:classpath:/config/"));
+		locations.add(ConfigDataLocation.of("optional:file:./"));
+		locations.add(ConfigDataLocation.of("optional:file:./config/*/"));
+		locations.add(ConfigDataLocation.of("optional:file:./config/"));
+		DEFAULT_SEARCH_LOCATIONS = locations.toArray(new ConfigDataLocation[0]);
+	};
+
+	private static final ConfigDataLocation[] EMPTY_LOCATIONS = new ConfigDataLocation[0];
 
 	private static final ConfigurationPropertyName INCLUDE_PROFILES = ConfigurationPropertyName
 			.of(Profiles.INCLUDE_PROFILES_PROPERTY_NAME);
 
+	private static final Bindable<ConfigDataLocation[]> CONFIG_DATA_LOCATION_ARRAY = Bindable
+			.of(ConfigDataLocation[].class);
+
 	private static final Bindable<List<String>> STRING_LIST = Bindable.listOf(String.class);
 
 	private final DeferredLogFactory logFactory;
 
 	private final Log logger;
 
+	private final ConfigDataNotFoundAction notFoundAction;
+
 	private final ConfigurableBootstrapContext bootstrapContext;
 
 	private final ConfigurableEnvironment environment;
@@ -122,25 +135,21 @@ class ConfigDataEnvironment {
 			ConfigurableEnvironment environment, ResourceLoader resourceLoader, Collection<String> additionalProfiles) {
 		Binder binder = Binder.get(environment);
 		UseLegacyConfigProcessingException.throwIfRequested(binder);
-		ConfigDataLocationNotFoundAction locationNotFoundAction = binder
-				.bind(ON_LOCATION_NOT_FOUND_PROPERTY, ConfigDataLocationNotFoundAction.class)
-				.orElse(ConfigDataLocationNotFoundAction.FAIL);
 		this.logFactory = logFactory;
 		this.logger = logFactory.getLog(getClass());
+		this.notFoundAction = binder.bind(ON_NOT_FOUND_PROPERTY, ConfigDataNotFoundAction.class)
+				.orElse(ConfigDataNotFoundAction.FAIL);
 		this.bootstrapContext = bootstrapContext;
 		this.environment = environment;
-		this.resolvers = createConfigDataLocationResolvers(logFactory, bootstrapContext, locationNotFoundAction, binder,
-				resourceLoader);
+		this.resolvers = createConfigDataLocationResolvers(logFactory, bootstrapContext, binder, resourceLoader);
 		this.additionalProfiles = additionalProfiles;
-		this.loaders = new ConfigDataLoaders(logFactory, bootstrapContext, locationNotFoundAction);
+		this.loaders = new ConfigDataLoaders(logFactory, bootstrapContext);
 		this.contributors = createContributors(binder);
 	}
 
 	protected ConfigDataLocationResolvers createConfigDataLocationResolvers(DeferredLogFactory logFactory,
-			ConfigurableBootstrapContext bootstrapContext, ConfigDataLocationNotFoundAction locationNotFoundAction,
-			Binder binder, ResourceLoader resourceLoader) {
-		return new ConfigDataLocationResolvers(logFactory, bootstrapContext, locationNotFoundAction, binder,
-				resourceLoader);
+			ConfigurableBootstrapContext bootstrapContext, Binder binder, ResourceLoader resourceLoader) {
+		return new ConfigDataLocationResolvers(logFactory, bootstrapContext, binder, resourceLoader);
 	}
 
 	private ConfigDataEnvironmentContributors createContributors(Binder binder) {
@@ -172,23 +181,26 @@ ConfigDataEnvironmentContributors getContributors() {
 
 	private List<ConfigDataEnvironmentContributor> getInitialImportContributors(Binder binder) {
 		List<ConfigDataEnvironmentContributor> initialContributors = new ArrayList<>();
+		addInitialImportContributors(initialContributors, bindLocations(binder, IMPORT_PROPERTY, EMPTY_LOCATIONS));
 		addInitialImportContributors(initialContributors,
-				binder.bind(IMPORT_PROPERTY, String[].class).orElse(EMPTY_LOCATIONS));
+				bindLocations(binder, ADDITIONAL_LOCATION_PROPERTY, EMPTY_LOCATIONS));
 		addInitialImportContributors(initialContributors,
-				binder.bind(ADDITIONAL_LOCATION_PROPERTY, String[].class).orElse(EMPTY_LOCATIONS));
-		addInitialImportContributors(initialContributors,
-				binder.bind(LOCATION_PROPERTY, String[].class).orElse(DEFAULT_SEARCH_LOCATIONS));
+				bindLocations(binder, LOCATION_PROPERTY, DEFAULT_SEARCH_LOCATIONS));
 		return initialContributors;
 	}
 
+	private ConfigDataLocation[] bindLocations(Binder binder, String propertyName, ConfigDataLocation[] other) {
+		return binder.bind(propertyName, CONFIG_DATA_LOCATION_ARRAY).orElse(other);
+	}
+
 	private void addInitialImportContributors(List<ConfigDataEnvironmentContributor> initialContributors,
-			String[] locations) {
+			ConfigDataLocation[] locations) {
 		for (int i = locations.length - 1; i >= 0; i--) {
 			initialContributors.add(createInitialImportContributor(locations[i]));
 		}
 	}
 
-	private ConfigDataEnvironmentContributor createInitialImportContributor(String location) {
+	private ConfigDataEnvironmentContributor createInitialImportContributor(ConfigDataLocation location) {
 		this.logger.trace(LogMessage.format("Adding initial config data import from location '%s'", location));
 		return ConfigDataEnvironmentContributor.ofInitialImport(location);
 	}
@@ -198,7 +210,8 @@ private ConfigDataEnvironmentContributor createInitialImportContributor(String l
 	 * {@link Environment}.
 	 */
 	void processAndApply() {
-		ConfigDataImporter importer = new ConfigDataImporter(this.resolvers, this.loaders);
+		ConfigDataImporter importer = new ConfigDataImporter(this.logFactory, this.notFoundAction, this.resolvers,
+				this.loaders);
 		this.bootstrapContext.register(Binder.class, InstanceSupplier
 				.from(() -> this.contributors.getBinder(null, BinderOption.FAIL_ON_BIND_TO_INACTIVE_SOURCE)));
 		ConfigDataEnvironmentContributors contributors = processInitial(this.contributors, importer);

Diff for: spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/config/ConfigDataEnvironmentContributor.java

@@ -28,7 +28,6 @@
 
 import org.springframework.boot.context.properties.bind.Binder;
 import org.springframework.boot.context.properties.source.ConfigurationPropertySource;
-import org.springframework.boot.origin.Origin;
 import org.springframework.core.env.Environment;
 import org.springframework.core.env.PropertySource;
 
@@ -52,7 +51,7 @@
  */
 class ConfigDataEnvironmentContributor implements Iterable<ConfigDataEnvironmentContributor> {
 
-	private final ConfigDataLocation location;
+	private final ConfigDataResource resource;
 
 	private final PropertySource<?> propertySource;
 
@@ -69,19 +68,19 @@ class ConfigDataEnvironmentContributor implements Iterable<ConfigDataEnvironment
 	/**
 	 * Create a new {@link ConfigDataEnvironmentContributor} instance.
 	 * @param kind the contributor kind
-	 * @param location the location that contributed the data or {@code null}
+	 * @param resource the resource that contributed the data or {@code null}
 	 * @param propertySource the property source for the data or {@code null}
 	 * @param configurationPropertySource the configuration property source for the data
 	 * or {@code null}
 	 * @param properties the config data properties or {@code null}
 	 * @param ignoreImports if import properties should be ignored
 	 * @param children the children of this contributor at each {@link ImportPhase}
 	 */
-	ConfigDataEnvironmentContributor(Kind kind, ConfigDataLocation location, PropertySource<?> propertySource,
+	ConfigDataEnvironmentContributor(Kind kind, ConfigDataResource resource, PropertySource<?> propertySource,
 			ConfigurationPropertySource configurationPropertySource, ConfigDataProperties properties,
 			boolean ignoreImports, Map<ImportPhase, List<ConfigDataEnvironmentContributor>> children) {
 		this.kind = kind;
-		this.location = location;
+		this.resource = resource;
 		this.properties = properties;
 		this.propertySource = propertySource;
 		this.configurationPropertySource = configurationPropertySource;
@@ -107,11 +106,11 @@ boolean isActive(ConfigDataActivationContext activationContext) {
 	}
 
 	/**
-	 * Return the location that contributed this instance.
-	 * @return the location or {@code null}
+	 * Return the resource that contributed this instance.
+	 * @return the resource or {@code null}
 	 */
-	ConfigDataLocation getLocation() {
-		return this.location;
+	ConfigDataResource getResource() {
+		return this.resource;
 	}
 
 	/**
@@ -134,14 +133,10 @@ ConfigurationPropertySource getConfigurationPropertySource() {
 	 * Return any imports requested by this contributor.
 	 * @return the imports
 	 */
-	List<String> getImports() {
+	List<ConfigDataLocation> getImports() {
 		return (this.properties != null) ? this.properties.getImports() : Collections.emptyList();
 	}
 
-	Origin getImportOrigin(String importLocation) {
-		return (this.properties != null) ? this.properties.getImportOrigin(importLocation) : null;
-	}
-
 	/**
 	 * Return true if this contributor has imports that have not yet been processed in the
 	 * given phase.
@@ -184,13 +179,19 @@ public Iterator<ConfigDataEnvironmentContributor> iterator() {
 		return new ContributorIterator();
 	}
 
+	/**
+	 * Create an new {@link ConfigDataEnvironmentContributor} with bound
+	 * {@link ConfigDataProperties}.
+	 * @param binder the binder to use
+	 * @return a new contributor instance
+	 */
 	ConfigDataEnvironmentContributor withBoundProperties(Binder binder) {
 		UseLegacyConfigProcessingException.throwIfRequested(binder);
 		ConfigDataProperties properties = ConfigDataProperties.get(binder);
 		if (this.ignoreImports) {
 			properties = properties.withoutImports();
 		}
-		return new ConfigDataEnvironmentContributor(Kind.BOUND_IMPORT, this.location, this.propertySource,
+		return new ConfigDataEnvironmentContributor(Kind.BOUND_IMPORT, this.resource, this.propertySource,
 				this.configurationPropertySource, properties, this.ignoreImports, null);
 	}
 
@@ -205,7 +206,7 @@ ConfigDataEnvironmentContributor withChildren(ImportPhase importPhase,
 			List<ConfigDataEnvironmentContributor> children) {
 		Map<ImportPhase, List<ConfigDataEnvironmentContributor>> updatedChildren = new LinkedHashMap<>(this.children);
 		updatedChildren.put(importPhase, children);
-		return new ConfigDataEnvironmentContributor(this.kind, this.location, this.propertySource,
+		return new ConfigDataEnvironmentContributor(this.kind, this.resource, this.propertySource,
 				this.configurationPropertySource, this.properties, this.ignoreImports, updatedChildren);
 	}
 
@@ -230,7 +231,7 @@ ConfigDataEnvironmentContributor withReplacement(ConfigDataEnvironmentContributo
 			}
 			updatedChildren.put(importPhase, Collections.unmodifiableList(updatedContributors));
 		});
-		return new ConfigDataEnvironmentContributor(this.kind, this.location, this.propertySource,
+		return new ConfigDataEnvironmentContributor(this.kind, this.resource, this.propertySource,
 				this.configurationPropertySource, this.properties, this.ignoreImports, updatedChildren);
 	}
 
@@ -249,11 +250,11 @@ static ConfigDataEnvironmentContributor of(List<ConfigDataEnvironmentContributor
 	 * Factory method to create a {@link Kind#INITIAL_IMPORT initial import} contributor.
 	 * This contributor is used to trigger initial imports of additional contributors. It
 	 * does not contribute any properties itself.
-	 * @param importLocation the initial import location (with placeholder resolved)
+	 * @param initialImport the initial import location (with placeholders resolved)
 	 * @return a new {@link ConfigDataEnvironmentContributor} instance
 	 */
-	static ConfigDataEnvironmentContributor ofInitialImport(String importLocation) {
-		List<String> imports = Collections.singletonList(importLocation);
+	static ConfigDataEnvironmentContributor ofInitialImport(ConfigDataLocation initialImport) {
+		List<ConfigDataLocation> imports = Collections.singletonList(initialImport);
 		ConfigDataProperties properties = new ConfigDataProperties(imports, null);
 		return new ConfigDataEnvironmentContributor(Kind.INITIAL_IMPORT, null, null, null, properties, false, null);
 	}
@@ -274,17 +275,17 @@ static ConfigDataEnvironmentContributor ofExisting(PropertySource<?> propertySou
 	 * Factory method to create an {@link Kind#UNBOUND_IMPORT unbound import} contributor.
 	 * This contributor has been actively imported from another contributor and may itself
 	 * import further contributors later.
-	 * @param location the location of imported config data
+	 * @param resource the condig data resource
 	 * @param configData the config data
 	 * @param propertySourceIndex the index of the property source that should be used
 	 * @return a new {@link ConfigDataEnvironmentContributor} instance
 	 */
-	static ConfigDataEnvironmentContributor ofUnboundImport(ConfigDataLocation location, ConfigData configData,
+	static ConfigDataEnvironmentContributor ofUnboundImport(ConfigDataResource resource, ConfigData configData,
 			int propertySourceIndex) {
 		PropertySource<?> propertySource = configData.getPropertySources().get(propertySourceIndex);
 		ConfigurationPropertySource configurationPropertySource = ConfigurationPropertySource.from(propertySource);
 		boolean ignoreImports = configData.getOptions().contains(ConfigData.Option.IGNORE_IMPORTS);
-		return new ConfigDataEnvironmentContributor(Kind.UNBOUND_IMPORT, location, propertySource,
+		return new ConfigDataEnvironmentContributor(Kind.UNBOUND_IMPORT, resource, propertySource,
 				configurationPropertySource, null, ignoreImports, null);
 	}
 

Diff for: spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/config/ConfigDataEnvironmentContributorPlaceholdersResolver.java

@@ -64,9 +64,9 @@ private String resolvePlaceholder(String placeholder) {
 			Object value = (propertySource != null) ? propertySource.getProperty(placeholder) : null;
 			if (value != null && !contributor.isActive(this.activationContext)) {
 				if (this.failOnResolveFromInactiveContributor) {
+					ConfigDataResource resource = contributor.getResource();
 					Origin origin = OriginLookup.getOrigin(propertySource, placeholder);
-					throw new InactiveConfigDataAccessException(propertySource, contributor.getLocation(), placeholder,
-							origin);
+					throw new InactiveConfigDataAccessException(propertySource, resource, placeholder, origin);
 				}
 				value = null;
 			}

Diff for: spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/config/ConfigDataEnvironmentContributors.java

@@ -39,7 +39,6 @@
 import org.springframework.boot.context.properties.source.ConfigurationPropertyName;
 import org.springframework.boot.context.properties.source.ConfigurationPropertySource;
 import org.springframework.boot.logging.DeferredLogFactory;
-import org.springframework.boot.origin.Origin;
 import org.springframework.core.log.LogMessage;
 import org.springframework.util.ObjectUtils;
 
@@ -114,12 +113,12 @@ ConfigDataEnvironmentContributors withProcessedImports(ConfigDataImporter import
 			ConfigDataLocationResolverContext locationResolverContext = new ContributorConfigDataLocationResolverContext(
 					result, contributor, activationContext);
 			ConfigDataLoaderContext loaderContext = new ContributorDataLoaderContext(this);
-			List<String> imports = contributor.getImports();
+			List<ConfigDataLocation> imports = contributor.getImports();
 			this.logger.trace(LogMessage.format("Processing imports %s", imports));
-			Map<ConfigDataLocation, ConfigData> imported = importer.resolveAndLoad(activationContext,
+			Map<ConfigDataResource, ConfigData> imported = importer.resolveAndLoad(activationContext,
 					locationResolverContext, loaderContext, imports);
 			this.logger.trace(LogMessage.of(() -> imported.isEmpty() ? "Nothing imported" : "Imported "
-					+ imported.size() + " location " + ((imported.size() != 1) ? "s" : "") + imported.keySet()));
+					+ imported.size() + " resource " + ((imported.size() != 1) ? "s" : "") + imported.keySet()));
 			ConfigDataEnvironmentContributor contributorAndChildren = contributor.withChildren(importPhase,
 					asContributors(imported));
 			result = new ConfigDataEnvironmentContributors(this.logger, this.bootstrapContext,
@@ -148,7 +147,7 @@ private boolean isActiveWithUnprocessedImports(ConfigDataActivationContext activ
 		return contributor.isActive(activationContext) && contributor.hasUnprocessedImports(importPhase);
 	}
 
-	private List<ConfigDataEnvironmentContributor> asContributors(Map<ConfigDataLocation, ConfigData> imported) {
+	private List<ConfigDataEnvironmentContributor> asContributors(Map<ConfigDataResource, ConfigData> imported) {
 		List<ConfigDataEnvironmentContributor> contributors = new ArrayList<>(imported.size() * 5);
 		imported.forEach((location, data) -> {
 			for (int i = data.getPropertySources().size() - 1; i >= 0; i--) {
@@ -259,20 +258,15 @@ public Binder getBinder() {
 		}
 
 		@Override
-		public ConfigDataLocation getParent() {
-			return this.contributor.getLocation();
+		public ConfigDataResource getParent() {
+			return this.contributor.getResource();
 		}
 
 		@Override
 		public ConfigurableBootstrapContext getBootstrapContext() {
 			return this.contributors.getBootstrapContext();
 		}
 
-		@Override
-		public Origin getLocationOrigin(String location) {
-			return this.contributor.getImportOrigin(location);
-		}
-
 	}
 
 	private class InactiveSourceChecker implements BindHandler {

Diff for: spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/config/ConfigDataEnvironmentPostProcessor.java

@@ -53,9 +53,9 @@ public class ConfigDataEnvironmentPostProcessor implements EnvironmentPostProces
 	/**
 	 * Property used to determine what action to take when a
 	 * {@code ConfigDataLocationNotFoundException} is thrown.
-	 * @see ConfigDataLocationNotFoundAction
+	 * @see ConfigDataNotFoundAction
 	 */
-	public static final String ON_LOCATION_NOT_FOUND_PROPERTY = ConfigDataEnvironment.ON_LOCATION_NOT_FOUND_PROPERTY;
+	public static final String ON_LOCATION_NOT_FOUND_PROPERTY = ConfigDataEnvironment.ON_NOT_FOUND_PROPERTY;
 
 	private final DeferredLogFactory logFactory;