Added support for parsing VEVENT from iCal format

Author: iainbeeston

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## Current
+
+* [FEATURE]     Added support for parsing VEVENT from iCal format (#465)
+
 ## 0.16.3 / 2018-07-23
 
 * [FEATURE]     Added support for parsing RDATE from iCal format

lib/ice_cube/parsers/ical_parser.rb

@@ -2,28 +2,57 @@ module IceCube
   class IcalParser
     def self.schedule_from_ical(ical_string, options = {})
       data = {}
+      parser = :parse_line
       ical_string.each_line do |line|
         (property, value) = line.split(':')
         (property, tzid) = property.split(';')
-        case property
+
+        parser, attr, occurrences = *send(parser, property, value)
+
+        case attr
+        when :start_time,
+             :end_time
+          data[attr] = occurrences
+        when :rtimes,
+             :rrules,
+             :extimes
+          data[attr] ||= []
+          data[attr] += occurrences
+        end
+      end
+      Schedule.from_hash data
+    end
+
+    def self.parse_line(property, value)
+      result = case property
         when 'DTSTART'
-          data[:start_time] = TimeUtil.deserialize_time(value)
+          [:parse_line, :start_time, TimeUtil.deserialize_time(value)]
         when 'DTEND'
-          data[:end_time] = TimeUtil.deserialize_time(value)
+          [:parse_line, :end_time, TimeUtil.deserialize_time(value)]
         when 'RDATE'
-          data[:rtimes] ||= []
-          data[:rtimes] += value.split(',').map { |v| TimeUtil.deserialize_time(v) }
+          [:parse_line, :rtimes, value.split(',').map { |v| TimeUtil.deserialize_time(v) }]
         when 'EXDATE'
-          data[:extimes] ||= []
-          data[:extimes] += value.split(',').map { |v| TimeUtil.deserialize_time(v) }
+          [:parse_line, :extimes, value.split(',').map { |v| TimeUtil.deserialize_time(v) }]
         when 'DURATION'
-          data[:duration] # FIXME
+          nil # FIXME
         when 'RRULE'
-          data[:rrules] ||= []
-          data[:rrules] += [rule_from_ical(value)]
+          [:parse_line, :rrules, [rule_from_ical(value)]]
+        when 'BEGIN'
+          [:parse_vevent_line] if value.chomp == 'VEVENT'
         end
-      end
-      Schedule.from_hash data
+
+      result || [:parse_line]
+    end
+
+    def self.parse_vevent_line(property, value)
+      result = case property
+        when 'DTSTART'
+          [:parse_vevent_line, :rtimes, [TimeUtil.deserialize_time(value)]]
+        when 'END'
+          [:parse_line] if value.chomp == 'VEVENT'
+        end
+
+      result || [:parse_vevent_line]
     end
 
     def self.rule_from_ical(ical)

spec/examples/from_ical_spec.rb

@@ -119,6 +119,17 @@ module IceCube
   RRULE:FREQ=WEEKLY;INTERVAL=2;WKST=SU;BYDAY=FR
     ICAL
 
+    ical_string_with_events = <<-ICAL.gsub(/^\s*/, '' )
+  BEGIN:VEVENT
+  DTSTART;VALUE=DATE:20120406
+  DTEND;VALUE=DATE:20120407
+  END:VEVENT
+  BEGIN:VEVENT
+  DTSTART;VALUE=DATE:20120409
+  DTEND;VALUE=DATE:20120410
+  END:VEVENT
+    ICAL
+
     def sorted_ical(ical)
       ical.split(/\n/).sort.map { |field|
         k, v = field.split(':')
@@ -383,13 +394,44 @@ def sorted_ical(ical)
       end
     end
 
+    describe 'one-off dates' do
+      it 'handles a specific day as a recurrence time' do
+        start_time = Time.now
+
+        schedule = IceCube::Schedule.new(start_time)
+        schedule.add_recurrence_time(start_time)
+
+        ical = schedule.to_ical
+        expect(sorted_ical(IceCube::Schedule.from_ical(ical).to_ical)).to eq(sorted_ical(ical))
+      end
+
+      it 'converts events to recurrence times' do
+        start_time = Time.utc(2019, 1, 16)
+
+        schedule = IceCube::Schedule.new(start_time)
+        schedule.add_recurrence_time(start_time)
+
+        event_ical = "DTSTART:20190116T000000Z\nBEGIN:VEVENT\nDTSTART:20190116T000000Z\nDTEND:20190117T000000Z\nEND:VEVENT"
+
+        ical = schedule.to_ical
+        expect(sorted_ical(IceCube::Schedule.from_ical(event_ical).to_ical)).to eq(sorted_ical(ical))
+      end
+    end
+
     describe 'multiple rules' do
       it 'handles multiple recurrence rules' do
         schedule = IceCube::Schedule.from_ical ical_string_with_multiple_rules
         expect(schedule.recurrence_rules.count).to eq(2)
       end
     end
 
+    describe 'events' do
+      it "converts each event into it's own recurrence time" do
+        schedule = IceCube::Schedule.from_ical ical_string_with_events
+        expect(schedule.recurrence_times.count).to eq(2)
+      end
+    end
+
     describe 'invalid ical data' do
       shared_examples_for('an invalid ical string') do
         it do