Add support for configuring the path of disk space metrics

See gh-27660

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/system/DiskSpaceMetricsBinder.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2012-2021 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.boot.actuate.metrics.system;
+
+import java.io.File;
+import java.util.List;
+
+import io.micrometer.core.instrument.MeterRegistry;
+import io.micrometer.core.instrument.Tag;
+import io.micrometer.core.instrument.binder.MeterBinder;
+import io.micrometer.core.instrument.binder.jvm.DiskSpaceMetrics;
+
+import org.springframework.util.Assert;
+
+/**
+ * A {@link MeterBinder} that binds one or more {@link DiskSpaceMetrics}.
+ *
+ * @author Chris Bono
+ * @since 2.6.0
+ */
+public class DiskSpaceMetricsBinder implements MeterBinder {
+
+	private final List<File> paths;
+
+	private final Iterable<Tag> tags;
+
+	public DiskSpaceMetricsBinder(List<File> paths, Iterable<Tag> tags) {
+		Assert.notEmpty(paths, "Paths must not be empty");
+		this.paths = paths;
+		this.tags = tags;
+	}
+
+	@Override
+	public void bindTo(MeterRegistry registry) {
+		this.paths.forEach((path) -> new DiskSpaceMetrics(path, this.tags).bindTo(registry));
+	}
+
+}

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/metrics/system/package-info.java

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+/*
+ * Copyright 2012-2021 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.
+ */
+
+/**
+ * Actuator support for system metrics.
+ */
+package org.springframework.boot.actuate.metrics.system;

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/metrics/system/DiskSpaceMetricsBinderTests.java

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+/*
+ * Copyright 2012-2021 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.boot.actuate.metrics.system;
+
+import java.io.File;
+import java.util.Arrays;
+import java.util.Collections;
+
+import io.micrometer.core.instrument.MeterRegistry;
+import io.micrometer.core.instrument.Tags;
+import io.micrometer.core.instrument.simple.SimpleMeterRegistry;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link DiskSpaceMetricsBinder}.
+ *
+ * @author Chris Bono
+ */
+class DiskSpaceMetricsBinderTests {
+
+	@Test
+	void diskSpaceMetricsWithSinglePath() {
+		MeterRegistry meterRegistry = new SimpleMeterRegistry();
+		File path = new File(".");
+		DiskSpaceMetricsBinder metricsBinder = new DiskSpaceMetricsBinder(Collections.singletonList(path),
+				Tags.empty());
+		metricsBinder.bindTo(meterRegistry);
+
+		Tags tags = Tags.of("path", path.getAbsolutePath());
+		assertThat(meterRegistry.get("disk.free").tags(tags).gauge()).isNotNull();
+		assertThat(meterRegistry.get("disk.total").tags(tags).gauge()).isNotNull();
+	}
+
+	@Test
+	void diskSpaceMetricsWithMultiplePaths() {
+		MeterRegistry meterRegistry = new SimpleMeterRegistry();
+		File path1 = new File(".");
+		File path2 = new File("..");
+		DiskSpaceMetricsBinder metricsBinder = new DiskSpaceMetricsBinder(Arrays.asList(path1, path2), Tags.empty());
+		metricsBinder.bindTo(meterRegistry);
+
+		Tags tags = Tags.of("path", path1.getAbsolutePath());
+		assertThat(meterRegistry.get("disk.free").tags(tags).gauge()).isNotNull();
+		assertThat(meterRegistry.get("disk.total").tags(tags).gauge()).isNotNull();
+		tags = Tags.of("path", path2.getAbsolutePath());
+		assertThat(meterRegistry.get("disk.free").tags(tags).gauge()).isNotNull();
+		assertThat(meterRegistry.get("disk.total").tags(tags).gauge()).isNotNull();
+	}
+
+	@Test
+	void diskSpaceMetricsWithCustomTags() {
+		MeterRegistry meterRegistry = new SimpleMeterRegistry();
+		File path = new File(".");
+		Tags customTags = Tags.of("foo", "bar");
+		DiskSpaceMetricsBinder metricsBinder = new DiskSpaceMetricsBinder(Collections.singletonList(path), customTags);
+		metricsBinder.bindTo(meterRegistry);
+
+		Tags tags = Tags.of("path", path.getAbsolutePath(), "foo", "bar");
+		assertThat(meterRegistry.get("disk.free").tags(tags).gauge()).isNotNull();
+		assertThat(meterRegistry.get("disk.total").tags(tags).gauge()).isNotNull();
+	}
+
+}