D-Net

package eu.dnetlib.msro.notification;

import java.util.Arrays;

import java.util.Date;

import java.util.Map;

import java.util.Properties;

import java.util.Set;

import java.util.concurrent.BlockingQueue;

import java.util.concurrent.LinkedBlockingQueue;

import javax.mail.Authenticator;

import javax.mail.Message;

import javax.mail.MessagingException;

import javax.mail.PasswordAuthentication;

import javax.mail.Session;

import javax.mail.Transport;

import javax.mail.internet.InternetAddress;

import javax.mail.internet.MimeMessage;

import org.antlr.stringtemplate.StringTemplate;

import org.apache.commons.io.IOUtils;

import org.apache.commons.logging.Log;

import org.apache.commons.logging.LogFactory;

import org.springframework.beans.factory.annotation.Required;

import com.google.common.base.Splitter;

import com.google.common.collect.Maps;

public class EmailDispatcher {

	private String from;

	private String fromName;

	private String cc;

	private String smtpHost;

	private int smtpPort = 587;

	private String smtpUser;

	private String smtpPassword;

	private String baseUrl;

	private static final Log log = LogFactory.getLog(EmailDispatcher.class);

	private final BlockingQueue<Message> queue = new LinkedBlockingQueue<Message>();

	public void sendMail(final Set<String> to, final String subject, final String template, final Map<String, Object> tmplParams) {

		try {

			final StringTemplate st = new StringTemplate(template);

			st.setAttributes(tmplParams);

			st.setAttribute("baseUrl", baseUrl);

			final Session session = Session.getInstance(obtainProperties(), obtainAuthenticator());

			final MimeMessage message = new MimeMessage(session);

			message.setFrom(new InternetAddress(from, fromName));

			message.setSubject(subject);

			message.setContent(st.toString(), "text/html; charset=utf-8");

			message.setSentDate(new Date());

			for (String s : to) {

				message.addRecipient(Message.RecipientType.TO, new InternetAddress(s));

			}

			if ((cc != null) && !cc.isEmpty()) {

				for (String aCC : Splitter.on(",").omitEmptyStrings().trimResults().split(getCc())) {

					message.addRecipient(Message.RecipientType.CC, new InternetAddress(aCC));

				}

			}

			queue.add(message);

			log.info("Mail to " + Arrays.toString(to.toArray()) + " in queue");

		} catch (Exception e) {

			log.error("Error sending mail", e);

		}

	}

	public void processMailQueue() {

		while (true) {

			final Message message = queue.poll();

			if (message == null) {

				return;

			} else {

				try {

					log.info("Sending mail...");

					Transport.send(message);

					log.info("...sent");

				} catch (MessagingException e) {

					log.error("Error sending email", e);

					queue.add(message);

					return;

				}

			}

		}

	}

	private void sendWfStatusMail(final boolean success,

			final Set<String> to,

			final String wfId,

			final String procId,

			final String wfName,

			final Map<String, String> pendingWfs,

			final Map<String, String> responses,

			final String error) {

		try {

			final Map<String, Object> map = Maps.newHashMap();

			map.put("wfId", wfId);

			map.put("wfName", wfName);

			map.put("procId", procId);

			if ((pendingWfs != null) && !pendingWfs.isEmpty()) {

				map.put("pendingWfs", pendingWfs);

			}

			if ((responses != null) && !responses.isEmpty()) {

				map.put("responses", responses);

			}

			if ((error != null) && !error.isEmpty()) {

				map.put("error", error);

			}

			final String subject = success ? "Workflow '" + wfName + "' has been completed successfully" : "Workflow '" + wfName + "' is failed";

			final String tmplName = success ? "wf_success.mail.st" : "wf_failed.mail.st";

			final String template = IOUtils.toString(getClass().getResourceAsStream("/eu/dnetlib/msro/mail/" + tmplName));

			sendMail(to, subject, template, map);

		} catch (Exception e) {

			log.error("Error generating success-mail", e);

		}

	}

	public void sendSuccessMail(final Set<String> to,

			final String wfId,

			final String procId,

			final String wfName,

			final Map<String, String> pendingWfs,

			final Map<String, String> responses) {

		sendWfStatusMail(true, to, wfId, procId, wfName, pendingWfs, responses, "");

	}

	public void sendFailedMail(final Set<String> to,

			final String wfId,

			final String procId,

			final String wfName,

			final Map<String, String> pendingWfs,

			final Map<String, String> responses,

			final String error) {

		sendWfStatusMail(false, to, wfId, procId, wfName, pendingWfs, responses, error);

	}

	private Properties obtainProperties() {

		final Properties props = new Properties();

		props.put("mail.transport.protocol", "smtp");

		props.put("mail.smtp.host", smtpHost);

		props.put("mail.smtp.port", smtpPort);

		props.put("mail.smtp.auth", Boolean.toString((smtpUser != null) && !smtpUser.isEmpty()));

		return props;

	}

	private Authenticator obtainAuthenticator() {

		if ((smtpUser == null) || smtpUser.isEmpty()) { return null; }

		return new Authenticator() {

			private final PasswordAuthentication authentication = new PasswordAuthentication(smtpUser, smtpPassword);

			@Override

			protected PasswordAuthentication getPasswordAuthentication() {

				return authentication;

			}

		};

	}

	public String getFrom() {

		return from;

	}

	@Required

	public void setFrom(final String from) {

		this.from = from;

	}

	public String getFromName() {

		return fromName;

	}

	@Required

	public void setFromName(final String fromName) {

		this.fromName = fromName;

	}

	public String getCc() {

		return cc;

	}

	@Required

	public void setCc(final String cc) {

		this.cc = cc;

	}

	public String getSmtpHost() {

		return smtpHost;

	}

	@Required

	public void setSmtpHost(final String smtpHost) {

		this.smtpHost = smtpHost;

	}

	public int getSmtpPort() {

		return smtpPort;

	}

	public void setSmtpPort(final int smtpPort) {

		this.smtpPort = smtpPort;

	}

	public String getSmtpUser() {

		return smtpUser;

	}

	public void setSmtpUser(final String smtpUser) {

		this.smtpUser = smtpUser;

	}

	public String getSmtpPassword() {

		return smtpPassword;

	}

	public void setSmtpPassword(final String smtpPassword) {

		this.smtpPassword = smtpPassword;

	}

	public String getBaseUrl() {

		return baseUrl;

	}

	@Required

	public void setBaseUrl(final String baseUrl) {

		this.baseUrl = baseUrl;

	}

}