Handling period durations of days with `T` prefix (#74) (c39b4544) · Commits · e / os / ical4android

src/androidTest/java/at/bitfire/ical4android/ICalPreprocessorTest.kt

+54 −3

Original line number	Diff line number	Diff line
		@@ -13,6 +13,7 @@ import org.junit.Assert.assertEquals
		import org.junit.Test
		import java.io.InputStreamReader
		import java.io.StringReader
		import java.time.Duration

		class ICalPreprocessorTest {

		@@ -56,10 +57,60 @@ class ICalPreprocessorTest {
		"TZNAME:EST" +
		"END:STANDARD\n" +
		"END:VTIMEZONE"
		ICalPreprocessor.fixInvalidUtcOffset(StringReader(invalid)).let { result ->
		ICalPreprocessor.preprocessStream(StringReader(invalid)).let { result ->
		assertEquals(valid, IOUtils.toString(result))
		}
		ICalPreprocessor.fixInvalidUtcOffset(StringReader(valid)).let { result ->
		ICalPreprocessor.preprocessStream(StringReader(valid)).let { result ->
		assertEquals(valid, IOUtils.toString(result))
		}
		}

		@Test
		fun testFixInvalidDuration() {
		val invalid = "BEGIN:VEVENT\n" +
		"LAST-MODIFIED:20230108T011226Z\n" +
		"DTSTAMP:20230108T011226Z\n" +
		"X-ECAL-SCHEDULE:63b0e38979739f000d5c1724\n" +
		"DTSTART:20230101T015100Z\n" +
		"DTEND:20230101T020600Z\n" +
		"SUMMARY:This is a test event\n" +
		"TRANSP:TRANSPARENT\n" +
		"SEQUENCE:0\n" +
		"UID:63b0e389453c5d000e1161ae\n" +
		"PRIORITY:5\n" +
		"X-MICROSOFT-CDO-IMPORTANCE:1\n" +
		"CLASS:PUBLIC\n" +
		"DESCRIPTION:Example description\n" +
		"BEGIN:VALARM\n" +
		"TRIGGER:-PT2D\n" +
		"ACTION:DISPLAY\n" +
		"DESCRIPTION:Reminder\n" +
		"END:VALARM\n" +
		"END:VEVENT"
		val valid = "BEGIN:VEVENT\n" +
		"LAST-MODIFIED:20230108T011226Z\n" +
		"DTSTAMP:20230108T011226Z\n" +
		"X-ECAL-SCHEDULE:63b0e38979739f000d5c1724\n" +
		"DTSTART:20230101T015100Z\n" +
		"DTEND:20230101T020600Z\n" +
		"SUMMARY:This is a test event\n" +
		"TRANSP:TRANSPARENT\n" +
		"SEQUENCE:0\n" +
		"UID:63b0e389453c5d000e1161ae\n" +
		"PRIORITY:5\n" +
		"X-MICROSOFT-CDO-IMPORTANCE:1\n" +
		"CLASS:PUBLIC\n" +
		"DESCRIPTION:Example description\n" +
		"BEGIN:VALARM\n" +
		"TRIGGER:-P2D\n" +
		"ACTION:DISPLAY\n" +
		"DESCRIPTION:Reminder\n" +
		"END:VALARM\n" +
		"END:VEVENT"
		ICalPreprocessor.preprocessStream(StringReader(invalid)).let { result ->
		assertEquals(valid, IOUtils.toString(result))
		}
		ICalPreprocessor.preprocessStream(StringReader(valid)).let { result ->
		assertEquals(valid, IOUtils.toString(result))
		}
		}
		@@ -72,7 +123,7 @@ class ICalPreprocessorTest {
		val vEvent = calendar.getComponent(Component.VEVENT) as VEvent

		assertEquals("W. Europe Standard Time", vEvent.startDate.timeZone.id)
		ICalPreprocessor.preProcess(calendar)
		ICalPreprocessor.preprocessCalendar(calendar)
		assertEquals("Europe/Vienna", vEvent.startDate.timeZone.id)
		}
		}

src/main/java/at/bitfire/ical4android/ICalendar.kt

+4 −4

Original line number	Diff line number	Diff line
		@@ -80,13 +80,13 @@ open class ICalendar {
		Ical4Android.log.fine("Parsing iCalendar stream")
		Ical4Android.checkThreadContextClassLoader()

		// apply hacks and workarounds that operate on plain text level
		val reader2 = ICalPreprocessor.fixInvalidUtcOffset(reader)
		// preprocess stream to work around some problems that can't be fixed later
		val preprocessed = ICalPreprocessor.preprocessStream(reader)

		// parse stream
		val calendar: Calendar
		try {
		calendar = CalendarBuilder().build(reader2)
		calendar = CalendarBuilder().build(preprocessed)
		} catch(e: ParserException) {
		throw InvalidCalendarException("Couldn't parse iCalendar", e)
		} catch(e: IllegalArgumentException) {
		@@ -95,7 +95,7 @@ open class ICalendar {

		// apply ICalPreprocessor for increased compatibility
		try {
		ICalPreprocessor.preProcess(calendar)
		ICalPreprocessor.preprocessCalendar(calendar)
		} catch (e: Exception) {
		Ical4Android.log.log(Level.WARNING, "Couldn't pre-process iCalendar", e)
		}

src/main/java/at/bitfire/ical4android/validation/FixInvalidDayOffsetPreprocessor.kt

0 → 100644

+30 −0

Original line number	Diff line number	Diff line
		/***************************************************************************************************
		* Copyright © All Contributors. See LICENSE and AUTHORS in the root directory for details.
		**************************************************************************************************/

		package at.bitfire.ical4android.validation

		/**
		* Fixes durations with day offsets with the 'T' prefix.
		* See also https://github.com/bitfireAT/icsx5/issues/100
		*/
		object FixInvalidDayOffsetPreprocessor : StreamPreprocessor() {

		override fun regexpForProblem() = Regex(
		"^(DURATION\|TRIGGER):-?PT-?\\d+D$",
		setOf(RegexOption.MULTILINE, RegexOption.IGNORE_CASE)
		)

		override fun fixString(original: String): String {
		var s: String = original

		// Find all matches for the expression
		val found = regexpForProblem().find(s) ?: return s
		for (match in found.groupValues) {
		val fixed = match.replace("PT", "P")
		s = s.replace(match, fixed)
		}
		return s
		}

		}
		No newline at end of file

src/main/java/at/bitfire/ical4android/validation/FixInvalidUtcOffsetPreprocessor.kt

0 → 100644

+31 −0

Original line number	Diff line number	Diff line
		/***************************************************************************************************
		* Copyright © All Contributors. See LICENSE and AUTHORS in the root directory for details.
		**************************************************************************************************/

		package at.bitfire.ical4android.validation

		import at.bitfire.ical4android.Ical4Android
		import at.bitfire.ical4android.validation.FixInvalidUtcOffsetPreprocessor.TZOFFSET_REGEXP
		import java.util.logging.Level


		/**
		* Some servers modify UTC offsets in TZOFFSET(FROM,TO) like "+005730" to an invalid "+5730".
		*
		* Rewrites values of all TZOFFSETFROM and TZOFFSETTO properties which match [TZOFFSET_REGEXP]
		* so that an hour value of 00 is inserted.
		*/
		object FixInvalidUtcOffsetPreprocessor: StreamPreprocessor() {

		private val TZOFFSET_REGEXP = Regex("^(TZOFFSET(FROM\|TO):[+\\-]?)((18\|19\|[2-6]\\d)\\d\\d)$",
		setOf(RegexOption.MULTILINE, RegexOption.IGNORE_CASE))

		override fun regexpForProblem() = TZOFFSET_REGEXP

		override fun fixString(original: String) =
		original.replace(TZOFFSET_REGEXP) {
		Ical4Android.log.log(Level.FINE, "Applying Synology WebDAV fix to invalid utc-offset", it.value)
		"${it.groupValues[1]}00${it.groupValues[3]}"
		}

		}
		No newline at end of file

src/main/java/at/bitfire/ical4android/validation/ICalPreprocessor.kt

+22 −52

Original line number	Diff line number	Diff line
		@@ -11,10 +11,7 @@ import net.fortuna.ical4j.transform.rfc5545.CreatedPropertyRule
		import net.fortuna.ical4j.transform.rfc5545.DateListPropertyRule
		import net.fortuna.ical4j.transform.rfc5545.DatePropertyRule
		import net.fortuna.ical4j.transform.rfc5545.Rfc5545PropertyRule
		import org.apache.commons.io.IOUtils
		import java.io.IOException
		import java.io.Reader
		import java.io.StringReader
		import java.util.*
		import java.util.logging.Level

		@@ -28,8 +25,6 @@ import java.util.logging.Level
		*/
		object ICalPreprocessor {

		private val TZOFFSET_REGEXP = Regex("^(TZOFFSET(FROM\|TO):[+\\-]?)((18\|19\|[2-6]\\d)\\d\\d)$", RegexOption.MULTILINE)

		private val propertyRules = arrayOf(
		CreatedPropertyRule(), // make sure CREATED is UTC

		@@ -37,46 +32,22 @@ object ICalPreprocessor {
		DateListPropertyRule(), // ... by the ical4j VTIMEZONE with the same TZID!
		)

		val streamPreprocessors = arrayOf(
		FixInvalidUtcOffsetPreprocessor, // fix things like TZOFFSET(FROM,TO):+5730
		FixInvalidDayOffsetPreprocessor // fix things like DURATION:PT2D
		)

		/**
		* Some servers modify UTC offsets in TZOFFSET(FROM,TO) like "+005730" to an invalid "+5730".
		*
		* Rewrites values of all TZOFFSETFROM and TZOFFSETTO properties which match [TZOFFSET_REGEXP]
		* so that an hour value of 00 is inserted.
		* Applies [streamPreprocessors] to a given [Reader] that reads an iCalendar object
		* in order to repair some things that must be fixed before parsing.
		*
		* @param reader Reader that reads the potentially broken iCalendar (which for instance contains `TZOFFSETFROM:+5730`)
		* @return Reader that reads the fixed iCalendar (for instance `TZOFFSETFROM:+005730`)
		* @param original original iCalendar object
		* @return the potentially repaired iCalendar object
		*/
		fun fixInvalidUtcOffset(reader: Reader): Reader {
		fun fixStringFromReader() =
		IOUtils.toString(reader).replace(TZOFFSET_REGEXP) {
		Ical4Android.log.log(Level.FINE, "Applying Synology WebDAV fix to invalid utc-offset", it.value)
		"${it.groupValues[1]}00${it.groupValues[3]}"
		}

		var result: String? = null

		val resetSupported = try {
		reader.reset()
		true
		} catch(e: IOException) {
		false
		}

		if (resetSupported) {
		// reset is supported, no need to copy the whole stream to another String (unless we have to fix the TZOFFSET)
		if (Scanner(reader).findWithinHorizon(TZOFFSET_REGEXP.toPattern(), 0) != null) {
		reader.reset()
		result = fixStringFromReader()
		}
		} else
		result = fixStringFromReader()

		if (result != null)
		return StringReader(result)

		// not modified, return original iCalendar
		reader.reset()
		fun preprocessStream(original: Reader): Reader {
		var reader = original
		for (preprocessor in streamPreprocessors)
		reader = preprocessor.preprocess(reader)
		return reader
		}

		@@ -86,12 +57,11 @@ object ICalPreprocessor {
		*
		* @param calendar the calendar object that is going to be modified
		*/
		fun preProcess(calendar: Calendar) {
		for (component in calendar.components) {
		fun preprocessCalendar(calendar: Calendar) {
		for (component in calendar.components)
		for (property in component.properties)
		applyRules(property)
		}
		}

		@Suppress("UNCHECKED_CAST")
		private fun applyRules(property: Property) {