org.graylog2.alarmcallbacks.HTTPAlarmCallback.java Source code

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Here is the source code for org.graylog2.alarmcallbacks.HTTPAlarmCallback.java

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/**
 * This file is part of Graylog.
 *
 * Graylog is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Graylog is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Graylog.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.graylog2.alarmcallbacks;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.google.common.collect.Maps;
import com.squareup.okhttp.MediaType;
import com.squareup.okhttp.OkHttpClient;
import com.squareup.okhttp.Request;
import com.squareup.okhttp.RequestBody;
import com.squareup.okhttp.Response;
import org.graylog2.plugin.alarms.AlertCondition;
import org.graylog2.plugin.alarms.callbacks.AlarmCallback;
import org.graylog2.plugin.alarms.callbacks.AlarmCallbackConfigurationException;
import org.graylog2.plugin.alarms.callbacks.AlarmCallbackException;
import org.graylog2.plugin.configuration.Configuration;
import org.graylog2.plugin.configuration.ConfigurationException;
import org.graylog2.plugin.configuration.ConfigurationRequest;
import org.graylog2.plugin.configuration.fields.ConfigurationField;
import org.graylog2.plugin.configuration.fields.TextField;
import org.graylog2.plugin.streams.Stream;

import javax.inject.Inject;

import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Map;

import static com.google.common.base.Strings.isNullOrEmpty;
import static javax.ws.rs.core.MediaType.APPLICATION_JSON;

public class HTTPAlarmCallback implements AlarmCallback {
    private static final String CK_URL = "url";
    private static final MediaType CONTENT_TYPE = MediaType.parse(APPLICATION_JSON + ";charset=utf-8;");

    private final OkHttpClient httpClient;
    private final ObjectMapper objectMapper;
    private Configuration configuration;

    @Inject
    public HTTPAlarmCallback(final OkHttpClient httpClient, final ObjectMapper objectMapper) {
        this.httpClient = httpClient;
        this.objectMapper = objectMapper;
    }

    @Override
    public void initialize(final Configuration config) throws AlarmCallbackConfigurationException {
        this.configuration = config;
    }

    @Override
    public void call(final Stream stream, final AlertCondition.CheckResult result) throws AlarmCallbackException {
        final Map<String, Object> event = Maps.newHashMap();
        event.put("stream", stream);
        event.put("check_result", result);

        final Response r;
        try {
            final byte[] body = objectMapper.writeValueAsBytes(event);
            final URL url = new URL(configuration.getString(CK_URL));
            final Request request = new Request.Builder().url(url).header("charset", "utf-8")
                    .header("content-type", "application/json").post(RequestBody.create(CONTENT_TYPE, body))
                    .build();
            r = httpClient.newCall(request).execute();
        } catch (JsonProcessingException e) {
            throw new AlarmCallbackException("Unable to serialize alarm", e);
        } catch (MalformedURLException e) {
            throw new AlarmCallbackException("Malformed URL", e);
        } catch (IOException e) {
            throw new AlarmCallbackException(e.getMessage(), e);
        }

        if (!r.isSuccessful()) {
            throw new AlarmCallbackException("Expected successful HTTP response [2xx] but got [" + r.code() + "].");
        }
    }

    @Override
    public ConfigurationRequest getRequestedConfiguration() {
        final ConfigurationRequest configurationRequest = new ConfigurationRequest();
        configurationRequest.addField(new TextField(CK_URL, "URL", "https://example.org/alerts",
                "The URL to POST to when an alert is triggered", ConfigurationField.Optional.NOT_OPTIONAL));

        return configurationRequest;
    }

    @Override
    public String getName() {
        return "HTTP Alarm Callback";
    }

    @Override
    public Map<String, Object> getAttributes() {
        return configuration.getSource();
    }

    @Override
    public void checkConfiguration() throws ConfigurationException {
        if (isNullOrEmpty(configuration.getString(CK_URL))) {
            throw new ConfigurationException("URL parameter is missing!");
        }

        try {
            new URL(configuration.getString(CK_URL));
        } catch (MalformedURLException e) {
            throw new ConfigurationException("Malformed URL", e);
        }
    }
}