https://gitlab.com/jottyfan/camporganizer2/-/issues/16

src/main/java/de/jottyfan/camporganizer/module/ical/ICalController.java

@@ -0,0 +1,31 @@
+package de.jottyfan.camporganizer.module.ical;
+
+import java.io.IOException;
+
+import javax.servlet.http.HttpServletResponse;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.GetMapping;
+
+/**
+ *
+ * @author jotty
+ *
+ */
+@Controller
+public class ICalController {
+
+	@Autowired
+	private IICalService service;
+
+	/**
+	 * generate the ical response stream
+	 *
+	 * @throws IOException on io errors
+	 */
+	@GetMapping("/ical")
+	public void generate(HttpServletResponse response) throws IOException {
+		service.generate(response);
+	}
+}

src/main/java/de/jottyfan/camporganizer/module/ical/IICalService.java

@@ -0,0 +1,23 @@
+package de.jottyfan.camporganizer.module.ical;
+
+import java.io.IOException;
+
+import javax.servlet.http.HttpServletResponse;
+
+/**
+ *
+ * @author jotty
+ *
+ */
+public interface IICalService {
+
+	/**
+	 * generate the ical
+	 *
+	 * @param response the response for the output stream
+	 *
+	 * @return true if successful, false otherwise
+	 * @throws IOException on io errors
+	 */
+	public Boolean generate(HttpServletResponse response) throws IOException;
+}

src/main/java/de/jottyfan/camporganizer/module/ical/impl/ICalGateway.java

@@ -0,0 +1,76 @@
+package de.jottyfan.camporganizer.module.ical.impl;
+
+import static de.jottyfan.camporganizer.db.jooq.Tables.T_CAMP;
+import static de.jottyfan.camporganizer.db.jooq.Tables.T_LOCATION;
+
+import java.time.LocalDateTime;
+import java.time.ZoneId;
+import java.util.Date;
+import java.util.TimeZone;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.jooq.DSLContext;
+import org.jooq.Record5;
+import org.jooq.SelectOnConditionStep;
+import org.jooq.exception.DataAccessException;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Repository;
+import org.springframework.transaction.annotation.Transactional;
+
+import biweekly.ICalendar;
+import biweekly.component.VEvent;
+import biweekly.io.TimezoneAssignment;
+import biweekly.property.Summary;
+
+/**
+*
+* @author jotty
+*
+*/
+@Repository
+@Transactional(transactionManager = "transactionManager")
+public class ICalGateway {
+	private static final Logger LOGGER = LogManager.getLogger(ICalGateway.class);
+
+	@Autowired
+	private DSLContext jooq;
+
+	/**
+	 * load all camp dates from db and generate an ical from it
+	 *
+	 * @return ical containing all (at least none) of the camp dates
+	 * @throws DataAccessException
+	 */
+	public ICalendar getIcal() throws DataAccessException {
+		SelectOnConditionStep<Record5<String, LocalDateTime, LocalDateTime, String, String>> sql = jooq
+		// @formatter:off
+			.select(T_CAMP.NAME,
+					    T_CAMP.ARRIVE,
+					    T_CAMP.DEPART,
+					    T_LOCATION.NAME,
+					    T_LOCATION.URL)
+			.from(T_CAMP)
+		  .leftJoin(T_LOCATION).on(T_LOCATION.PK.eq(T_CAMP.FK_LOCATION));
+		// @formatter:on
+		LOGGER.debug(sql.toString());
+		ICalendar ical = new ICalendar();
+		ical.getTimezoneInfo().setDefaultTimezone(TimezoneAssignment.download(TimeZone.getTimeZone("Europe/Berlin"), false));
+		for (Record5<String, LocalDateTime, LocalDateTime, String, String> r : sql.fetch()) {
+			VEvent event = new VEvent();
+			Summary summary = event.setSummary(r.get(T_CAMP.NAME));
+			summary.setLanguage("de");
+			LocalDateTime startDate = r.get(T_CAMP.ARRIVE);
+			LocalDateTime endDate = r.get(T_CAMP.DEPART);
+			// because of the specification, end dates are exclusive - and without time, the day won't be counted
+			endDate = endDate.plusDays(1l);
+			event.setLocation(r.get(T_LOCATION.NAME));
+			event.setDateStart(startDate == null ? null : Date.from(startDate.atZone(ZoneId.of("Europe/Berlin")).toInstant()), false);
+			event.setDateEnd(endDate == null ? null : Date.from(endDate.atZone(ZoneId.of("Europe/Berlin")).toInstant()), false);
+			event.setUrl(r.get(T_LOCATION.URL));
+			event.setDescription("zur Anmeldung: http://anmeldung.onkelwernerfreizeiten.de");
+			ical.addEvent(event);
+		}
+		return ical;
+	}
+}

src/main/java/de/jottyfan/camporganizer/module/ical/impl/ICalService.java

@@ -0,0 +1,41 @@
+package de.jottyfan.camporganizer.module.ical.impl;
+
+import java.io.IOException;
+
+import javax.servlet.http.HttpServletResponse;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+import biweekly.Biweekly;
+import biweekly.ICalendar;
+import de.jottyfan.camporganizer.module.ical.IICalService;
+
+/**
+ *
+ * @author jotty
+ *
+ */
+@Service
+public class ICalService implements IICalService {
+
+	@Autowired
+	private ICalGateway gateway;
+
+	@Override
+	public Boolean generate(HttpServletResponse response) throws IOException {
+		ICalendar ical = gateway.getIcal();
+		String content = Biweekly.write(ical).go();
+
+		response.setHeader("charset", "UTF-8");
+		response.setHeader("Content-Type", "text/calendar");
+		response.setHeader("Content-Disposition", "attachment; filename=\"onkelwernerfreizeiten.de.ics\"");
+
+		response.getWriter().write(content);
+		response.getWriter().flush();
+		response.flushBuffer();
+
+		return true;
+	}
+
+}

src/main/resources/templates/index.html

@@ -7,15 +7,15 @@
 </head>
 <body>
 	<header>
-		<a th:href="@{/}" class="btn btn-secondary btn-icon-silent" title="aktualisieren"><i class="fas fa-sync"></i></a>
-		<span>Das Buchungsportal des Onkel Werner Freizeiten e.V.</span>
+		<a th:href="@{/ical}" class="btn btn-secondary btn-icon-silent" target="_blank" title="Freizeitdaten als ical herunterladen"><i class="far fa-calendar-alt"></i></a> <a th:href="@{/}"
+			class="btn btn-secondary btn-icon-silent" title="aktualisieren"><i class="fas fa-sync"></i></a>
+		<a class="btn btn-icon-silent" style="color: black !important; font-size: larger" href="http://anmeldung.onkelwernerfreizeiten.de">Unsere Freizeiten</a>
 	</header>
 	<content>
 	<div class="mainpage">
 		<script type="text/javascript">
 			var mytoggle = new MyToggle();
 		</script>
-		<h1>Unsere Freizeiten</h1>
 		<div class="card bottomdist16" th:each="c : ${camps}">
 			<div class="card-header mytoggle_btn" th:onclick="mytoggle.toggle('campdiv_[[${c.pk}]]')">
 				<span th:text="${c.name}"></span>&nbsp;<span th:text="${#numbers.formatInteger(c.year, 0)}" th:if="${c.year != null}"></span>