Java tutorial
/** * 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 com.jive.myco.seyren.core.service.notification; import static com.google.common.collect.Iterables.*; import java.util.ArrayList; import java.util.List; import javax.inject.Inject; import javax.inject.Named; import org.apache.http.HttpResponse; import org.apache.http.client.HttpClient; import org.apache.http.client.entity.UrlEncodedFormEntity; import org.apache.http.client.methods.HttpPost; import org.apache.http.client.utils.HttpClientUtils; import org.apache.http.impl.client.BasicResponseHandler; import org.apache.http.impl.client.HttpClientBuilder; import org.apache.http.message.BasicNameValuePair; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.google.common.base.Function; import com.google.common.base.Joiner; import com.google.common.base.Splitter; import com.google.common.collect.Iterables; import com.google.common.collect.Lists; import com.jive.myco.seyren.core.domain.Alert; import com.jive.myco.seyren.core.domain.Check; import com.jive.myco.seyren.core.domain.Subscription; import com.jive.myco.seyren.core.domain.SubscriptionType; import com.jive.myco.seyren.core.exception.NotificationFailedException; import com.jive.myco.seyren.core.util.config.SeyrenConfig; @Named public class SlackNotificationService implements NotificationService { private static final Logger LOGGER = LoggerFactory.getLogger(SlackNotificationService.class); private final SeyrenConfig seyrenConfig; private final String baseUrl; @Inject public SlackNotificationService(SeyrenConfig seyrenConfig) { this.seyrenConfig = seyrenConfig; this.baseUrl = "https://slack.com"; } protected SlackNotificationService(SeyrenConfig seyrenConfig, String baseUrl) { this.seyrenConfig = seyrenConfig; this.baseUrl = baseUrl; } @Override public void sendNotification(Check check, Subscription subscription, List<Alert> alerts) throws NotificationFailedException { String token = seyrenConfig.getSlackToken(); String channel = subscription.getTarget(); String username = seyrenConfig.getSlackUsername(); String iconUrl = seyrenConfig.getSlackIconUrl(); List<String> emojis = Lists.newArrayList( Splitter.on(',').omitEmptyStrings().trimResults().split(seyrenConfig.getSlackEmojis())); String url = String.format("%s/api/chat.postMessage", baseUrl); HttpClient client = HttpClientBuilder.create().build(); HttpPost post = new HttpPost(url); post.addHeader("accept", "application/json"); List<BasicNameValuePair> parameters = new ArrayList<BasicNameValuePair>(); parameters.add(new BasicNameValuePair("token", token)); parameters.add(new BasicNameValuePair("channel", channel)); parameters.add(new BasicNameValuePair("text", formatContent(emojis, check, subscription, alerts))); parameters.add(new BasicNameValuePair("username", username)); parameters.add(new BasicNameValuePair("icon_url", iconUrl)); try { post.setEntity(new UrlEncodedFormEntity(parameters)); HttpResponse response = client.execute(post); if (LOGGER.isDebugEnabled()) { LOGGER.debug("Status: {}, Body: {}", response.getStatusLine(), new BasicResponseHandler().handleResponse(response)); } } catch (Exception e) { LOGGER.warn("Error posting to Slack", e); } finally { post.releaseConnection(); HttpClientUtils.closeQuietly(client); } } @Override public boolean canHandle(SubscriptionType subscriptionType) { return subscriptionType == SubscriptionType.SLACK; } private String formatContent(List<String> emojis, Check check, Subscription subscription, List<Alert> alerts) { String url = String.format("%s/#/checks/%s", seyrenConfig.getBaseUrl(), check.getId()); String alertsString = Joiner.on(", ").join(transform(alerts, new Function<Alert, String>() { @Override public String apply(Alert input) { return String.format("%s: %s", input.getTarget(), input.getValue().toString()); } })); return String.format("[%s] %s %s has entered its %s state - [%s] - %s", Iterables.getFirst(alerts, null).getTimestamp(), Iterables.get(emojis, check.getState().ordinal(), ""), check.getName(), check.getState().toString(), alertsString, url); } }