org.vbossica.springbox.metrics.HealthCheckController.java Source code

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Here is the source code for org.vbossica.springbox.metrics.HealthCheckController.java

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/*
 * Copyright 2012-2013 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
 *
 *      http://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.vbossica.springbox.metrics;

import com.codahale.metrics.health.HealthCheck;
import com.codahale.metrics.health.HealthCheckRegistry;
import com.codahale.metrics.json.HealthCheckModule;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;

import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Map;
import java.util.SortedMap;

import static javax.servlet.http.HttpServletResponse.*;

@Controller
public class HealthCheckController implements InitializingBean {

    @Autowired
    private HealthCheckRegistry registry;
    private ObjectMapper mapper;

    @Override
    public void afterPropertiesSet() throws Exception {
        mapper = new ObjectMapper().registerModule(new HealthCheckModule());
    }

    @RequestMapping(value = "/metrics/healthcheck", method = RequestMethod.GET)
    public void process(
            @RequestParam(value = "pretty", required = false, defaultValue = "true") boolean prettyPrint,
            HttpServletResponse resp) throws IOException {
        SortedMap<String, HealthCheck.Result> results = registry.runHealthChecks();
        resp.setContentType("application/json");
        resp.setHeader("Cache-Control", "must-revalidate,no-cache,no-store");
        if (results.isEmpty()) {
            resp.setStatus(SC_NOT_IMPLEMENTED);
        } else {
            resp.setStatus(isAllHealthy(results) ? SC_OK : SC_INTERNAL_SERVER_ERROR);
        }

        OutputStream output = resp.getOutputStream();
        try {
            (prettyPrint ? mapper.writerWithDefaultPrettyPrinter() : mapper.writer()).writeValue(output, results);
        } finally {
            output.close();
        }
    }

    private boolean isAllHealthy(Map<String, HealthCheck.Result> results) {
        for (HealthCheck.Result result : results.values()) {
            if (!result.isHealthy()) {
                return false;
            }
        }
        return true;
    }

}