Adds timezone drop down for dynamic configuration modals

laoer · Oct 28, 2021 · 5b39367 · 5b39367
1 parent e6f2fb2
commit 5b39367
Show file tree

Hide file tree

Showing 2 changed files with 96 additions and 2 deletions.
diff --git a/graylog2-server/src/main/java/org/graylog2/plugin/configuration/fields/DropdownField.java b/graylog2-server/src/main/java/org/graylog2/plugin/configuration/fields/DropdownField.java
@@ -17,10 +17,19 @@
 package org.graylog2.plugin.configuration.fields;
 
 import com.google.common.collect.Maps;
+import org.graylog2.shared.SuppressForbidden;
+import org.joda.time.DateTime;
+import org.joda.time.DateTimeZone;
+import org.joda.time.Instant;
 
+import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Comparator;
+import java.util.LinkedHashMap;
+import java.util.List;
 import java.util.Locale;
 import java.util.Map;
+import java.util.TreeMap;
 import java.util.concurrent.TimeUnit;
 import java.util.function.Function;
 import java.util.stream.Collectors;
@@ -31,6 +40,8 @@ public class DropdownField extends AbstractConfigurationField {
 
     private String defaultValue;
     private final Map<String, String> values;
+    private static final int MILLIS_PER_HOUR = 3600000;
+    private static final int MILLIS_PER_MINUTE = 60000;
 
     public DropdownField(String name, String humanName, String defaultValue, Map<String, String> values, Optional isOptional) {
         this(name, humanName, defaultValue, values, null, isOptional);
@@ -79,10 +90,63 @@ public static Map<String, String> timeUnits() {
             return units;
         }
 
+        /**
+         * Returns a sorted map of available Time Zones that is first sorted by UTC offset and then alphabetically
+         *
+         * @return map of sorted timezones
+         */
+        public static Map<String, String> timeZones() {
+            Map<Integer, List<DateTimeZone>> offsetsAndTimezones = buildSortedTimeZoneMap();
+            Map<String, String> timezones = new LinkedHashMap<>();
+            for (List<DateTimeZone> dtzList : offsetsAndTimezones.values()) {
+                for (DateTimeZone dtz : dtzList) {
+                    timezones.put(dtz.getID(), buildTimeZoneDisplayName(dtz));
+                }
+            }
+            return timezones;
+        }
+
         public static Map<String, String> valueMapFromEnum(Class<? extends Enum> enumClass, Function<Enum, String> valueMapping) {
             return Arrays.stream(enumClass.getEnumConstants()).collect(Collectors.toMap(Enum::toString, valueMapping));
         }
 
+        // Builds an ordered map of timezones sorted first by the timezone offset (keys of the TreeMap) and then
+        // alphabetically the timezones in that specific offset. Iterating over the map and keys maintains that order
+        @SuppressForbidden("Intentionally use system default timezone")
+        private static Map<Integer, List<DateTimeZone>> buildSortedTimeZoneMap() {
+            // get a sorted list of DateTimeZones based on their IDs
+            List<DateTimeZone> dtzList = DateTimeZone.getAvailableIDs().stream()
+                    .map(DateTimeZone::forID)
+                    .sorted(Comparator.comparing(DateTimeZone::getID, String.CASE_INSENSITIVE_ORDER))
+                    .collect(Collectors.toList());
+
+            // iterate over the sorted list and group each DateTimeZone by offset
+            // TreeMap is an implementation of an OrderedMap where keys are ordered
+            Map<Integer, List<DateTimeZone>> offsetsAndTimezones = new TreeMap<>();
+            Instant now = new DateTime(DateTimeZone.getDefault()).toInstant();
+            for (DateTimeZone dtz : dtzList) {
+                int rawOffset = dtz.getOffset(now);
+                List<DateTimeZone> timezonesForOffset = offsetsAndTimezones.getOrDefault(rawOffset, new ArrayList<>());
+                timezonesForOffset.add(dtz);
+                offsetsAndTimezones.put(rawOffset, timezonesForOffset);
+            }
+
+            return offsetsAndTimezones;
+        }
+
+        @SuppressForbidden("Intentionally use system default timezone")
+        private static String buildTimeZoneDisplayName(DateTimeZone dtz) {
+            Instant now = new DateTime(DateTimeZone.getDefault()).toInstant();
+            int offset = dtz.getOffset(now);
+            int offsetHours = offset / MILLIS_PER_HOUR;
+            int remainderOffset = offset % MILLIS_PER_HOUR;
+            if (remainderOffset < 0) {
+                remainderOffset *= -1;
+            }
+            // some timezones have a half hour or three-quarter hour offsets included - handle them here
+            int offsetMinutes = remainderOffset / MILLIS_PER_MINUTE;
+            return String.format(Locale.getDefault(), "UTC%+03d:%02d - %s", offsetHours, offsetMinutes, dtz.getID());
+        }
     }
 
 }
diff --git a/...c/test/java/org/graylog2/plugin/configuration/fields/DropdownFieldValueTemplatesTest.java b/...c/test/java/org/graylog2/plugin/configuration/fields/DropdownFieldValueTemplatesTest.java
@@ -16,6 +16,10 @@
  */
 package org.graylog2.plugin.configuration.fields;
 
+import org.graylog2.shared.SuppressForbidden;
+import org.joda.time.DateTime;
+import org.joda.time.DateTimeZone;
+import org.joda.time.Instant;
 import org.junit.Test;
 
 import java.util.Locale;
@@ -32,7 +36,33 @@ private enum TestEnum {
     public void testBuildEnumMap() throws Exception {
         final Map<String, String> enumMap = DropdownField.ValueTemplates.valueMapFromEnum(TestEnum.class, (t) -> t.name().toLowerCase(Locale.ENGLISH));
         assertThat(enumMap)
-            .containsEntry("ONE", "one")
-            .containsEntry("TWO", "two");
+                .containsEntry("ONE", "one")
+                .containsEntry("TWO", "two");
+    }
+
+    /**
+     * Test that the timezone map for DropdownFields is ordered first by offset and then alphabetically
+     */
+    @Test
+    @SuppressForbidden("Intentionally use system default timezone")
+    public void testBuildTimeZoneMap() {
+        Map<String, String> timezones = DropdownField.ValueTemplates.timeZones();
+        DateTimeZone curDTZ = null;
+        int curOffset = 0;
+        Instant now = new DateTime().withZone(DateTimeZone.getDefault()).toInstant();
+        for (String tz : timezones.keySet()) {
+            DateTimeZone nextDTZ = DateTimeZone.forID(tz);
+            int nextOffset = nextDTZ.getOffset(now);
+            if (curDTZ != null) {
+                // current offset should always be less than or equal to the next
+                assertThat(curOffset).isLessThanOrEqualTo(nextOffset);
+                // if the timezones have the same offset, current should come before next alphabetically
+                if (curOffset == nextOffset) {
+                    assertThat(curDTZ.getID().toLowerCase().compareTo(nextDTZ.getID().toLowerCase())).isLessThan(0);
+                }
+            }
+            curDTZ = nextDTZ;
+            curOffset = nextOffset;
+        }
     }
 }