de.codecentric.boot.admin.services.ApplicationRegistrator.java Source code

Introduction

Here is the source code for de.codecentric.boot.admin.services.ApplicationRegistrator.java

Source

/*
 * Copyright 2014 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 de.codecentric.boot.admin.services;

import java.util.Collections;
import java.util.Map;
import java.util.concurrent.atomic.AtomicReference;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.web.client.RestTemplate;

import de.codecentric.boot.admin.config.AdminClientProperties;
import de.codecentric.boot.admin.config.AdminProperties;
import de.codecentric.boot.admin.model.Application;

/**
 * Registers the client application at spring-boot-admin-server
 */
public class ApplicationRegistrator {

    private static final Logger LOGGER = LoggerFactory.getLogger(ApplicationRegistrator.class);

    private static HttpHeaders HTTP_HEADERS = createHttpHeaders();

    private final AtomicReference<String> registeredId = new AtomicReference<>();

    private AdminClientProperties client;

    private AdminProperties admin;

    private final RestTemplate template;

    public ApplicationRegistrator(RestTemplate template, AdminProperties admin, AdminClientProperties client) {
        this.client = client;
        this.admin = admin;
        this.template = template;
    }

    private static HttpHeaders createHttpHeaders() {
        HttpHeaders headers = new HttpHeaders();
        headers.setContentType(MediaType.APPLICATION_JSON);
        headers.setAccept(Collections.singletonList(MediaType.APPLICATION_JSON));
        return HttpHeaders.readOnlyHttpHeaders(headers);
    }

    /**
     * Registers the client application at spring-boot-admin-server.
     *
     * @return true if successful registration on at least one admin server
     */
    public boolean register() {
        boolean isRegistrationSuccessful = false;
        Application self = createApplication();
        for (String adminUrl : admin.getAdminUrl()) {
            try {
                @SuppressWarnings("rawtypes")
                ResponseEntity<Map> response = template.postForEntity(adminUrl,
                        new HttpEntity<>(self, HTTP_HEADERS), Map.class);

                if (response.getStatusCode().equals(HttpStatus.CREATED)) {
                    if (registeredId.compareAndSet(null, response.getBody().get("id").toString())) {
                        LOGGER.info("Application registered itself as {}", response.getBody());
                    } else {
                        LOGGER.debug("Application refreshed itself as {}", response.getBody());
                    }

                    isRegistrationSuccessful = true;
                    if (admin.isRegisterOnce()) {
                        break;
                    }
                } else {
                    LOGGER.warn("Application failed to registered itself as {}. Response: {}", self,
                            response.toString());
                }
            } catch (Exception ex) {
                LOGGER.warn("Failed to register application as {} at spring-boot-admin ({}): {}", self,
                        admin.getAdminUrl(), ex.getMessage());
            }
        }

        return isRegistrationSuccessful;
    }

    public void deregister() {
        String id = registeredId.get();
        if (id != null) {
            for (String adminUrl : admin.getAdminUrl()) {
                try {
                    template.delete(adminUrl + "/" + id);
                    registeredId.compareAndSet(id, null);
                    if (admin.isRegisterOnce()) {
                        break;
                    }
                } catch (Exception ex) {
                    LOGGER.warn("Failed to deregister application (id={}) at spring-boot-admin ({}): {}", id,
                            adminUrl, ex.getMessage());
                }
            }
        }
    }

    protected Application createApplication() {
        return Application.create(client.getName()).withHealthUrl(client.getHealthUrl())
                .withManagementUrl(client.getManagementUrl()).withServiceUrl(client.getServiceUrl()).build();
    }
}