Initial support for HclPropertySourceLoader

spring-cloud-consul-config/pom.xml

@@ -37,6 +37,11 @@
 			<artifactId>consul-api</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>com.bertramlabs.plugins</groupId>
+			<artifactId>hcl4j</artifactId>
+			<version>0.3.3</version>
+		</dependency>
 		<dependency>
 			<groupId>org.springframework.cloud</groupId>
 			<artifactId>spring-cloud-consul-core</artifactId>

spring-cloud-consul-config/src/main/java/org/springframework/cloud/consul/hcl/HclPropertySourceLoader.java

@@ -0,0 +1,121 @@
+/*
+ * Copyright 2013-2020 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
+ *
+ *      https://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.cloud.consul.hcl;
+
+import java.io.IOException;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+
+import com.bertramlabs.plugins.hcl4j.HCLParser;
+import com.bertramlabs.plugins.hcl4j.HCLParserException;
+
+import org.springframework.beans.factory.config.YamlProcessor;
+import org.springframework.boot.env.OriginTrackedMapPropertySource;
+import org.springframework.boot.env.PropertySourceLoader;
+import org.springframework.core.env.PropertySource;
+import org.springframework.core.io.Resource;
+import org.springframework.lang.Nullable;
+import org.springframework.util.StringUtils;
+
+public class HclPropertySourceLoader implements PropertySourceLoader {
+
+	@Override
+	public String[] getFileExtensions() {
+		return new String[] {"hcl"};
+	}
+
+	@Override
+	public List<PropertySource<?>> load(String name, Resource resource) throws IOException {
+		Map<String, ?> properties = loadProperties(resource);
+		if (properties.isEmpty()) {
+			return Collections.emptyList();
+		}
+		return Collections
+			.singletonList(new OriginTrackedMapPropertySource(name, Collections
+				.unmodifiableMap(properties), true));
+
+	}
+
+	private Map<String, ?> loadProperties(Resource resource) throws IOException {
+		try {
+			Map<String, Object> map = new HCLParser().parse(resource.getInputStream());
+			map = getFlattenedMap(map);
+			return map;
+		}
+		catch (HCLParserException e) {
+			throw new IOException("Error parsing " + resource.getFilename(), e);
+		}
+	}
+
+	/**
+	 * Return a flattened version of the given map, recursively following any nested Map
+	 * or Collection values. Entries from the resulting map retain the same order as the
+	 * source. When called with the Map from a {@link YamlProcessor.MatchCallback} the result will
+	 * contain the same values as the {@link YamlProcessor.MatchCallback} Properties.
+	 * @param source the source map
+	 * @return a flattened map
+	 * @since 4.1.3
+	 */
+	protected final Map<String, Object> getFlattenedMap(Map<String, Object> source) {
+		Map<String, Object> result = new LinkedHashMap<>();
+		buildFlattenedMap(result, source, null);
+		return result;
+	}
+
+	private void buildFlattenedMap(Map<String, Object> result, Map<String, Object> source, @Nullable String path) {
+		source.forEach((key, value) -> {
+			if (StringUtils.hasText(path)) {
+				if (key.startsWith("[")) {
+					key = path + key;
+				}
+				else {
+					key = path + '.' + key;
+				}
+			}
+			if (value instanceof String) {
+				result.put(key, value);
+			}
+			else if (value instanceof Map) {
+				// Need a compound key
+				@SuppressWarnings("unchecked")
+				Map<String, Object> map = (Map<String, Object>) value;
+				buildFlattenedMap(result, map, key);
+			}
+			else if (value instanceof Collection) {
+				// Need a compound key
+				@SuppressWarnings("unchecked")
+				Collection<Object> collection = (Collection<Object>) value;
+				if (collection.isEmpty()) {
+					result.put(key, "");
+				}
+				else {
+					int count = 0;
+					for (Object object : collection) {
+						buildFlattenedMap(result, Collections.singletonMap(
+							"[" + (count++) + "]", object), key);
+					}
+				}
+			}
+			else {
+				result.put(key, (value != null ? value : ""));
+			}
+		});
+	}
+}

spring-cloud-consul-config/src/main/resources/META-INF/spring.factories

@@ -4,3 +4,7 @@ org.springframework.cloud.consul.config.ConsulConfigAutoConfiguration
 # Bootstrap Configuration
 org.springframework.cloud.bootstrap.BootstrapConfiguration=\
 org.springframework.cloud.consul.config.ConsulConfigBootstrapConfiguration
+
+# PropertySource Loaders
+org.springframework.boot.env.PropertySourceLoader=\
+org.springframework.cloud.consul.hcl.HclPropertySourceLoader

spring-cloud-consul-config/src/test/java/org/springframework/cloud/consul/hcl/HclPropertySourceLoaderIntegrationTests.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2013-2020 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
+ *
+ *      https://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.cloud.consul.hcl;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.SpringBootConfiguration;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.core.env.Environment;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@SpringBootTest(properties = { "spring.cloud.consul.config.enabled=false",
+		"spring.profiles.active=hcltest" })
+public class HclPropertySourceLoaderIntegrationTests {
+
+	@Autowired
+	Environment env;
+
+	@Test
+	void loadProperties() throws Exception {
+		assertThat(env.getProperty("variable.region.description"))
+				.isEqualTo("This is the location where the Linode instance is deployed.");
+	}
+
+	@SpringBootConfiguration
+	protected static class TestConfig {
+
+	}
+
+}

spring-cloud-consul-config/src/test/java/org/springframework/cloud/consul/hcl/HclPropertySourceLoaderTests.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2013-2020 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
+ *
+ *      https://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.cloud.consul.hcl;
+
+import java.util.List;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.core.env.PropertySource;
+import org.springframework.core.io.ClassPathResource;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class HclPropertySourceLoaderTests {
+
+	private HclPropertySourceLoader loader = new HclPropertySourceLoader();
+
+	@Test
+	void getFileExtensions() {
+		assertThat(this.loader.getFileExtensions()).isEqualTo(new String[] { "hcl" });
+	}
+
+	@Test
+	void loadProperties() throws Exception {
+		List<PropertySource<?>> loaded = this.loader.load("test.hcl",
+				new ClassPathResource("test.hcl", getClass()));
+		PropertySource<?> source = loaded.get(0);
+		assertThat(source.getProperty("variable.region.description"))
+				.isEqualTo("This is the location where the Linode instance is deployed.");
+	}
+}

spring-cloud-consul-config/src/test/resources/application-hcltest.hcl

@@ -0,0 +1,19 @@
+# Linode provider block. Installs Linode plugin.
+provider "linode" {
+	token = "${var.token}"
+}
+
+variable "region" {
+	description = "This is the location where the Linode instance is deployed."
+}
+
+/* A multi
+   line comment. */
+resource "linode_instance" "example_linode" {
+	image = "linode/ubuntu18.04"
+	label = "example-linode"
+	region = "${var.region}"
+	type = "g6-standard-1"
+	authorized_keys = [ "my-key" ]
+	root_pass = "example-password"
+}

spring-cloud-consul-config/src/test/resources/org/springframework/cloud/consul/hcl/test.hcl

@@ -0,0 +1,19 @@
+# Linode provider block. Installs Linode plugin.
+provider "linode" {
+	token = "${var.token}"
+}
+
+variable "region" {
+	description = "This is the location where the Linode instance is deployed."
+}
+
+/* A multi
+   line comment. */
+resource "linode_instance" "example_linode" {
+	image = "linode/ubuntu18.04"
+	label = "example-linode"
+	region = "${var.region}"
+	type = "g6-standard-1"
+	authorized_keys = [ "my-key" ]
+	root_pass = "example-password"
+}