spring boot admin slack報警

slack配置

spring.boot.admin:
  notify:
    slack:
      enabled: true
      ignore-changes: #empty, nothing to ignore
      webhook-url: https://hooks.slack.com/services/xxxxxxx
      channel: general
      username: spring cloud admin
      message: "*#{application.name}* (#{application.id}) is *#{to.status}*"

排程配置

@Configuration
@EnableScheduling
public class NotifierConfiguration {

    @Autowired
    private Notifier notifier;

    @Bean
    @Primary
    public RemindingNotifier remindingNotifier() {
        RemindingNotifier remindingNotifier = new RemindingNotifier(notifier);
        //時間視窗,每次報警的間隔,即這個時間視窗內不重複報警
        remindingNotifier.setReminderPeriod(TimeUnit.SECONDS.toMillis(10));
        return remindingNotifier;
    }

    @Scheduled(fixedRate = 5_000L) //每5秒排程一次
    public void remind() {
        System.out.println("remind....");
        remindingNotifier().sendReminders();
    }
}

時間視窗

~/.m2/repository/de/codecentric/spring-boot-admin-server/1.4.6/spring-boot-admin-server-1.4.6-sources.jar!/de/codecentric/boot/admin/notify/RemindingNotifier.java

    public void sendReminders() {
        long now = System.currentTimeMillis();
        for (Reminder reminder : new ArrayList<>(reminders.values())) {
            if (now - reminder.getLastNotification() > reminderPeriod) {
                reminder.setLastNotification(now);
                delegate.notify(reminder.getEvent());
            }
        }
    }

是否該報警的判斷

    private String[] reminderStatuses = { "DOWN", "OFFLINE" };

    @Override
    public void doNotify(ClientApplicationEvent event) {
        delegate.notify(event);
        if (shouldEndReminder(event)) {
            reminders.remove(event.getApplication().getId());
        } else if (shouldStartReminder(event)) {
            reminders.putIfAbsent(event.getApplication().getId(), new Reminder(event));
        }
    }

    public void sendReminders() {
        long now = System.currentTimeMillis();
        for (Reminder reminder : new ArrayList<>(reminders.values())) {
            if (now - reminder.getLastNotification() > reminderPeriod) {
                reminder.setLastNotification(now);
                delegate.notify(reminder.getEvent());
            }
        }
    }

    protected boolean shouldStartReminder(ClientApplicationEvent event) {
        if (event instanceof ClientApplicationStatusChangedEvent) {
            return Arrays.binarySearch(reminderStatuses,
                    event.getApplication().getStatusInfo().getStatus()) >= 0;
        }
        return false;
    }

    protected boolean shouldEndReminder(ClientApplicationEvent event) {
        if (event instanceof ClientApplicationDeregisteredEvent) {
            return true;
        }
        if (event instanceof ClientApplicationStatusChangedEvent) {
            return Arrays.binarySearch(reminderStatuses,
                    event.getApplication().getStatusInfo().getStatus()) < 0;
        }
        return false;
    }

狀態在{"DOWN", "OFFLINE"}的，就加入到reminders中，不在的話，從reminders中移除。
在排程期間，如果status變為up了，會先報警，然後再判斷是否應該刪除該事件。

notifier

delegate.notify(event);

這裡的delegate為SlackNotifier

public class SlackNotifier extends AbstractStatusChangeNotifier {
   //...
}

繼承了AbstractStatusChangeNotifier

public abstract class AbstractStatusChangeNotifier extends AbstractEventNotifier {

    /**
     * List of changes to ignore. Must be in Format OLD:NEW, for any status use * as wildcard, e.g.
     * *:UP or OFFLINE:*
     */
    private String[] ignoreChanges = { "UNKNOWN:UP" };

    @Override
    protected boolean shouldNotify(ClientApplicationEvent event) {
        if (event instanceof ClientApplicationStatusChangedEvent) {
            ClientApplicationStatusChangedEvent statusChange = (ClientApplicationStatusChangedEvent) event;
            String from = statusChange.getFrom().getStatus();
            String to = statusChange.getTo().getStatus();
            return Arrays.binarySearch(ignoreChanges, from + ":" + to) < 0
                    && Arrays.binarySearch(ignoreChanges, "*:" + to) < 0
                    && Arrays.binarySearch(ignoreChanges, from + ":*") < 0;
        }
        return false;
    }

    public void setIgnoreChanges(String[] ignoreChanges) {
        String[] copy = Arrays.copyOf(ignoreChanges, ignoreChanges.length);
        Arrays.sort(copy);
        this.ignoreChanges = copy;
    }

}

這裡對ignore的邏輯進行了判斷，不滿足條件的不會呼叫doNotify

public void notify(ClientApplicationEvent event) {
        if (enabled && shouldNotify(event)) {
            try {
                doNotify(event);
            } catch (Exception ex) {
                getLogger().error("Couldn't notify for event {} ", event, ex);
            }
        }
    }

doNotify才是真正的傳送slack

    @Override
    protected void doNotify(ClientApplicationEvent event) throws Exception {
        restTemplate.postForEntity(webhookUrl, createMessage(event), Void.class);
    }

例項

doc

• notifications