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/* * Copyright 2012-2019 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.health; import java.util.Collections; import java.util.LinkedHashMap; import java.util.Map; import com.fasterxml.jackson.annotation.JsonInclude; import com.fasterxml.jackson.annotation.JsonInclude.Include; import com.fasterxml.jackson.annotation.JsonUnwrapped; import org.springframework.util.Assert; /** * Carries information about the health of a component or subsystem. * <p> * {@link Health} contains a {@link Status} to express the state of a component or * subsystem and some additional details to carry some contextual information. * <p> * {@link Health} instances can be created by using {@link Builder}'s fluent API. Typical * usage in a {@link HealthIndicator} would be: * * <pre class="code"> * try { * // do some test to determine state of component * return new Health.Builder().up().withDetail("version", "1.1.2").build(); * } * catch (Exception ex) { * return new Health.Builder().down(ex).build(); * } * </pre> * * @author Christian Dupuis * @author Phillip Webb * @author Michael Pratt * @since 1.1.0 */ @JsonInclude(Include.NON_EMPTY) public final class Health { private final Status status; private final Map<String, Object> details; /** * Create a new {@link Health} instance with the specified status and details. * @param builder the Builder to use */ private Health(Builder builder) { Assert.notNull(builder, "Builder must not be null"); this.status = builder.status; this.details = Collections.unmodifiableMap(builder.details); } /** * Return the status of the health. * @return the status (never {@code null}) */ @JsonUnwrapped public Status getStatus() { return this.status; } /** * Return the details of the health. * @return the details (or an empty map) */ public Map<String, Object> getDetails() { return this.details; } @Override public boolean equals(Object obj) { if (obj == this) { return true; } if (obj != null && obj instanceof Health) { Health other = (Health) obj; return this.status.equals(other.status) && this.details.equals(other.details); } return false; } @Override public int hashCode() { int hashCode = this.status.hashCode(); return 13 * hashCode + this.details.hashCode(); } @Override public String toString() { return getStatus() + " " + getDetails(); } /** * Create a new {@link Builder} instance with an {@link Status#UNKNOWN} status. * @return a new {@link Builder} instance */ public static Builder unknown() { return status(Status.UNKNOWN); } /** * Create a new {@link Builder} instance with an {@link Status#UP} status. * @return a new {@link Builder} instance */ public static Builder up() { return status(Status.UP); } /** * Create a new {@link Builder} instance with an {@link Status#DOWN} status and the * specified exception details. * @param ex the exception * @return a new {@link Builder} instance */ public static Builder down(Exception ex) { return down().withException(ex); } /** * Create a new {@link Builder} instance with a {@link Status#DOWN} status. * @return a new {@link Builder} instance */ public static Builder down() { return status(Status.DOWN); } /** * Create a new {@link Builder} instance with an {@link Status#OUT_OF_SERVICE} status. * @return a new {@link Builder} instance */ public static Builder outOfService() { return status(Status.OUT_OF_SERVICE); } /** * Create a new {@link Builder} instance with a specific status code. * @param statusCode the status code * @return a new {@link Builder} instance */ public static Builder status(String statusCode) { return status(new Status(statusCode)); } /** * Create a new {@link Builder} instance with a specific {@link Status}. * @param status the status * @return a new {@link Builder} instance */ public static Builder status(Status status) { return new Builder(status); } /** * Builder for creating immutable {@link Health} instances. */ public static class Builder { private Status status; private Map<String, Object> details; /** * Create new Builder instance. */ public Builder() { this.status = Status.UNKNOWN; this.details = new LinkedHashMap<>(); } /** * Create new Builder instance, setting status to given {@code status}. * @param status the {@link Status} to use */ public Builder(Status status) { Assert.notNull(status, "Status must not be null"); this.status = status; this.details = new LinkedHashMap<>(); } /** * Create new Builder instance, setting status to given {@code status} and details * to given {@code details}. * @param status the {@link Status} to use * @param details the details {@link Map} to use */ public Builder(Status status, Map<String, ?> details) { Assert.notNull(status, "Status must not be null"); Assert.notNull(details, "Details must not be null"); this.status = status; this.details = new LinkedHashMap<>(details); } /** * Record detail for given {@link Exception}. * @param ex the exception * @return this {@link Builder} instance */ public Builder withException(Throwable ex) { Assert.notNull(ex, "Exception must not be null"); return withDetail("error", ex.getClass().getName() + ": " + ex.getMessage()); } /** * Record detail using given {@code key} and {@code value}. * @param key the detail key * @param value the detail value * @return this {@link Builder} instance */ public Builder withDetail(String key, Object value) { Assert.notNull(key, "Key must not be null"); Assert.notNull(value, "Value must not be null"); this.details.put(key, value); return this; } /** * Record details from the given {@code details} map. Keys from the given map * replace any existing keys if there are duplicates. * @param details map of details * @return this {@link Builder} instance * @since 2.1.0 */ public Builder withDetails(Map<String, ?> details) { Assert.notNull(details, "Details must not be null"); this.details.putAll(details); return this; } /** * Set status to {@link Status#UNKNOWN} status. * @return this {@link Builder} instance */ public Builder unknown() { return status(Status.UNKNOWN); } /** * Set status to {@link Status#UP} status. * @return this {@link Builder} instance */ public Builder up() { return status(Status.UP); } /** * Set status to {@link Status#DOWN} and add details for given {@link Throwable}. * @param ex the exception * @return this {@link Builder} instance */ public Builder down(Throwable ex) { return down().withException(ex); } /** * Set status to {@link Status#DOWN}. * @return this {@link Builder} instance */ public Builder down() { return status(Status.DOWN); } /** * Set status to {@link Status#OUT_OF_SERVICE}. * @return this {@link Builder} instance */ public Builder outOfService() { return status(Status.OUT_OF_SERVICE); } /** * Set status to given {@code statusCode}. * @param statusCode the status code * @return this {@link Builder} instance */ public Builder status(String statusCode) { return status(new Status(statusCode)); } /** * Set status to given {@link Status} instance. * @param status the status * @return this {@link Builder} instance */ public Builder status(Status status) { this.status = status; return this; } /** * Create a new {@link Health} instance with the previously specified code and * details. * @return a new {@link Health} instance */ public Health build() { return new Health(this); } } }