Merge pull request #12 from InsanusMokrassar/0.5.0

0.5.0

CHANGELOG.md

@@ -1,5 +1,24 @@
 # Changelog
 
+## 0.5.0 Years
+
+**BREAKING CHANGES**
+
+* `CronDateTimeScheduler` has been marked as `internal` and no longer accessible outside of internal functions
+  * Old methods `merge` and `plus` related to `CronDateTimeScheduler` has been marked as `deprecated` and changed their
+  parameters types - it is `KronScheduler` now
+* New methods `merge` has been added
+* **`KronScheduler#next` method now is nullable. Use `nextOrRelative`/`nextOrNow` to get next time certainly**
+* **Years was added as optional part of krontab template and opportunity in `SchedulerBuilder`**
+  * New builder `YearsBuilder`
+  * `SchedulerFlow#collectSafely` will be normally (without exceptions) finish when `next` of scheduler will return
+    null
+* `KronScheduler#doOnce` will run code immediately in case when `next` is returning null value
+* `KrontabTemplateWrapper` has been added
+* New extension `KrontabTemplate#toKronScheduler` (works as `toSchedule`)
+* **Fixed issue related to the fact that `toNearDateTime` of `CronDateTime` incorrectly handled months
+* **Android target has been added**
+
 ## 0.4.2
 
 * Versions

README.md

@@ -53,18 +53,18 @@ For old version of Gradle, instead of `implementation` word developers must use
 Developers can use more simple way to configure repeat times is string. String configuring
 like a `crontab`, but with a little bit different meanings:
 ```
-/-------- Seconds
-| /------ Minutes
-| | /---- Hours
-| | | /-- Days of months
-| | | | / Months
-| | | | |
-* * * * *
+/---------- Seconds
+| /-------- Minutes
+| | /------ Hours
+| | | /---- Days of months
+| | | | /-- Months
+| | | | | / (optional) Year
+* * * * * *
 ```
 
 It is different with original `crontab` syntax for the reason, that expected that in practice developers
-will use seconds and minutes with more probability than months (for example). In fact, developers will use something
-like:
+will use seconds and minutes with more probability than months (for example) or even years. In fact, developers will use
+something like:
 
 ```kotlin
 doWhile("/5 * * * *") {
@@ -73,7 +73,7 @@ doWhile("/5 * * * *") {
 }
 ```
 
-Or more version:
+An other version:
 
 ```kotlin
 doInfinity("/5 * * * *") {
@@ -85,7 +85,7 @@ Both of examples will print `Called` message every five seconds.
 
 ### Config via builder
 
-Also this library currently supports DSL for creating the same goals:
+Also, this library currently supports DSL for creating the same goals:
 
 ```kotlin
 val kronScheduler = buildSchedule {

build.gradle

@@ -3,11 +3,14 @@ buildscript {
         mavenLocal()
         jcenter()
         mavenCentral()
+        google()
     }
 
     dependencies {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         classpath "com.github.breadmoirai:github-release:$github_release_plugin_version"
+        classpath "com.getkeepsafe.dexcount:dexcount-gradle-plugin:$dexcount_version"
+        classpath 'com.android.tools.build:gradle:4.0.2'
     }
 }
 
@@ -15,8 +18,9 @@ plugins {
     id "org.jetbrains.kotlin.multiplatform" version "$kotlin_version"
     id "org.jetbrains.dokka" version "$dokka_version"
 }
+apply plugin: "com.android.library"
 
-project.version = "0.4.2"
+project.version = "$version"
 project.group = "dev.inmo"
 
 apply from: "publish.gradle"
@@ -27,6 +31,7 @@ repositories {
     jcenter()
     mavenCentral()
     maven { url "https://kotlin.bintray.com/kotlinx" }
+    google()
 }
 
 apply from: './dokka.gradle'
@@ -37,6 +42,9 @@ kotlin {
         browser()
         nodejs()
     }
+    android {
+        publishAllLibraryVariants()
+    }
 
 
     sourceSets {
@@ -48,6 +56,13 @@ kotlin {
                 api "com.soywiz.korlibs.klock:klock:$klockVersion"
             }
         }
+
+        androidMain {
+            dependencies {
+                api "androidx.work:work-runtime-ktx:$androidx_work_version"
+            }
+        }
+
         commonTest {
             dependencies {
                 implementation kotlin('test-common')
@@ -64,5 +79,48 @@ kotlin {
                 implementation kotlin('test-js')
             }
         }
+        androidTest {
+            dependencies {
+                implementation kotlin('test-junit')
+            }
+        }
+    }
+}
+
+apply plugin: 'com.getkeepsafe.dexcount'
+
+android {
+    compileSdkVersion "$android_compileSdkVersion".toInteger()
+    buildToolsVersion "$android_buildToolsVersion"
+
+    defaultConfig {
+        minSdkVersion "$android_minSdkVersion".toInteger()
+        targetSdkVersion "$android_compileSdkVersion".toInteger()
+        versionCode "${android_code_version}".toInteger()
+        versionName "$version"
+    }
+    buildTypes {
+        release {
+            minifyEnabled false
+        }
+        debug {
+            debuggable true
+        }
+    }
+
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
+
+    kotlinOptions {
+        jvmTarget = JavaVersion.VERSION_1_8.toString()
+    }
+
+    sourceSets {
+        main.java.srcDirs += 'src/main/kotlin'
+        test {
+            java.srcDir file("src/jvmTest")
+        }
     }
 }

gradle.properties

@@ -4,6 +4,8 @@ kotlin.js.generate.externals=true
 kotlin.incremental=true
 kotlin.incremental.js=true
 kotlin.incremental.multiplatform=true
+android.useAndroidX=true
+android.enableJetifier=false
 
 
 kotlin_version=1.4.21
@@ -13,5 +15,24 @@ dokka_version=1.4.20
 
 klockVersion=2.0.3
 
+## Github reease
+
 github_release_plugin_version=2.2.12
 
+## Android
+
+android_minSdkVersion=19
+android_compileSdkVersion=30
+android_buildToolsVersion=30.0.2
+dexcount_version=2.0.0
+junit_version=4.12
+test_ext_junit_version=1.1.2
+espresso_core=3.3.0
+
+androidx_work_version=2.4.0
+
+## Common
+
+version=0.5.0
+android_code_version=1
+

src/commonMain/kotlin/dev/inmo/krontab/Executes.kt

@@ -7,9 +7,13 @@ import kotlinx.coroutines.delay
  * Execute [block] once at the [KronScheduler.next] time and return result of [block] calculation.
  *
  * WARNING!!! If you want to launch it in parallel, you must do this explicitly.
+ *
+ * WARNING!!! In case if [KronScheduler.next] of [this] instance will return null, [block] will be called immediately
  */
 suspend inline fun <T> KronScheduler.doOnce(noinline block: suspend () -> T): T {
-    delay((next() - DateTime.now()).millisecondsLong)
+    next() ?.let {
+        delay((it - DateTime.now()).millisecondsLong)
+    }
     return block()
 }
 

src/commonMain/kotlin/dev/inmo/krontab/KronScheduler.kt

@@ -1,6 +1,7 @@
 package dev.inmo.krontab
 
 import com.soywiz.klock.DateTime
+import dev.inmo.krontab.internal.toNearDateTime
 
 /**
  * This interface was created for abstraction of [next] operation. Currently, there is only
@@ -17,5 +18,10 @@ interface KronScheduler {
      *
      * @see dev.inmo.krontab.internal.CronDateTimeScheduler.next
      */
-    suspend fun next(relatively: DateTime = DateTime.now()): DateTime
+    suspend fun next(relatively: DateTime = DateTime.now()): DateTime?
+}
+
+suspend fun KronScheduler.nextOrRelative(relatively: DateTime = DateTime.now()): DateTime = next(relatively) ?: getAnyNext(relatively)
+suspend fun KronScheduler.nextOrNow(): DateTime = DateTime.now().let {
+    next(it) ?: getAnyNext(it)
 }

src/commonMain/kotlin/dev/inmo/krontab/KronSchedulersMerging.kt

@@ -0,0 +1,41 @@
+package dev.inmo.krontab
+
+import dev.inmo.krontab.collection.CollectionKronScheduler
+import dev.inmo.krontab.internal.CronDateTime
+import dev.inmo.krontab.internal.CronDateTimeScheduler
+
+/**
+ * Create new one [CollectionKronScheduler] to include all [KronScheduler]s of [this] [Iterator]
+ *
+ * @see CollectionKronScheduler
+ * @see CollectionKronScheduler.include
+ */
+fun Iterator<KronScheduler>.merge(): KronScheduler {
+    val cronDateTimes = mutableListOf<CronDateTime>()
+    val collectionScheduler = CollectionKronScheduler()
+    forEach {
+        when (it) {
+            is CronDateTimeScheduler -> cronDateTimes.addAll(it.cronDateTimes)
+            else -> collectionScheduler.include(it)
+        }
+    }
+    if (cronDateTimes.isNotEmpty()) {
+        collectionScheduler.include(CronDateTimeScheduler(cronDateTimes))
+    }
+    return collectionScheduler
+}
+
+/**
+ * Create new one [CollectionKronScheduler] to include all [KronScheduler]s of [this] [Iterator]
+ *
+ * @see CollectionKronScheduler
+ * @see CollectionKronScheduler.include
+ */
+@Suppress("NOTHING_TO_INLINE")
+inline fun Iterable<KronScheduler>.merge(): KronScheduler = iterator().merge()
+
+/**
+ * @return Vararg shortcut for [merge]
+ */
+@Suppress("NOTHING_TO_INLINE")
+inline fun merge(vararg kronDateTimeSchedulers: KronScheduler) = kronDateTimeSchedulers.iterator().merge()

src/commonMain/kotlin/dev/inmo/krontab/KrontabTemplateWrapper.kt

@@ -0,0 +1,18 @@
+package dev.inmo.krontab
+
+/**
+ * This class contains [template] and can be simply serialized/deserialized. In fact that class will work as
+ * [dev.inmo.krontab.internal.CronDateTimeScheduler] due to the fact that [toKronScheduler] will return it under the
+ * hood
+ */
+data class KrontabTemplateWrapper(
+    val template: KrontabTemplate
+) : KronScheduler by template.toKronScheduler()
+
+/**
+ * Will create [KrontabTemplateWrapper] from [this] [KrontabTemplate]
+ *
+ * @see [toKronScheduler]
+ * @see [KrontabTemplateWrapper]
+ */
+fun KrontabTemplate.wrapAsKronScheduler() = KrontabTemplateWrapper(this)

src/commonMain/kotlin/dev/inmo/krontab/SchedulerShortcuts.kt

@@ -1,12 +1,15 @@
 package dev.inmo.krontab
 
+import com.soywiz.klock.DateTime
 import dev.inmo.krontab.builder.buildSchedule
+import dev.inmo.krontab.internal.*
 import dev.inmo.krontab.internal.CronDateTime
 import dev.inmo.krontab.internal.CronDateTimeScheduler
 
 internal val anyCronDateTime by lazy {
     CronDateTime()
 }
+internal fun getAnyNext(relatively: DateTime) = anyCronDateTime.toNearDateTime(relatively)!!
 
 /**
  * [KronScheduler.next] will always return [com.soywiz.klock.DateTime.now]
@@ -48,4 +51,11 @@ val EveryDayOfMonthScheduler: KronScheduler by lazy {
  */
 val EveryMonthScheduler: KronScheduler by lazy {
     buildSchedule { months { 0 every 1 } }
+}
+
+/**
+ * [KronScheduler.next] will always return [com.soywiz.klock.DateTime.now] + one year
+ */
+val EveryYearScheduler: KronScheduler by lazy {
+    buildSchedule { years { 0 every 1 } }
 }

src/commonMain/kotlin/dev/inmo/krontab/StringParser.kt

@@ -16,6 +16,7 @@ typealias KrontabTemplate = String
  * * hours
  * * dayOfMonth
  * * month
+ * * (optional) year
  *
  * And each one have next format:
  *
@@ -37,6 +38,7 @@ typealias KrontabTemplate = String
  * * Hours ranges can be found in [hoursRange]
  * * Days of month ranges can be found in [dayOfMonthRange]
  * * Months ranges can be found in [monthRange]
+ * * Years ranges can be found in [yearRange] (in fact - any [Int])
  *
  * Examples:
  *
@@ -44,20 +46,25 @@ typealias KrontabTemplate = String
  * * "0/5,L * * * *" for every five seconds triggering and on 59 second
  * * "0/15 30 * * *" for every 15th seconds in a half of each hour
  * * "1 2 3 F,4,L 5" for triggering in near first second of second minute of third hour of fourth day of may
+ * * "1 2 3 F,4,L 5 2021" for triggering in near first second of second minute of third hour of fourth day of may of 2021st year
  *
  * @see dev.inmo.krontab.internal.createKronScheduler
  */
 fun createSimpleScheduler(incoming: KrontabTemplate): KronScheduler {
-    val (secondsSource, minutesSource, hoursSource, dayOfMonthSource, monthSource) = incoming.split(" ")
+    val yearSource: String?
+    val (secondsSource, minutesSource, hoursSource, dayOfMonthSource, monthSource) = incoming.split(" ").also {
+        yearSource = it.getOrNull(5)
+    }
 
     val secondsParsed = parseSeconds(secondsSource)
     val minutesParsed = parseMinutes(minutesSource)
     val hoursParsed = parseHours(hoursSource)
     val dayOfMonthParsed = parseDaysOfMonth(dayOfMonthSource)
     val monthParsed = parseMonths(monthSource)
+    val yearParsed = parseYears(yearSource)
 
     return createKronScheduler(
-        secondsParsed, minutesParsed, hoursParsed, dayOfMonthParsed, monthParsed
+        secondsParsed, minutesParsed, hoursParsed, dayOfMonthParsed, monthParsed, yearParsed
     )
 }
 
@@ -69,4 +76,9 @@ fun buildSchedule(incoming: KrontabTemplate): KronScheduler = createSimpleSchedu
 /**
  * Shortcut for [buildSchedule]
  */
-fun KrontabTemplate.toSchedule(): KronScheduler = buildSchedule(this)
+fun KrontabTemplate.toSchedule(): KronScheduler = buildSchedule(this)
+
+/**
+ * Shortcut for [buildSchedule]
+ */
+fun KrontabTemplate.toKronScheduler(): KronScheduler = buildSchedule(this)

src/commonMain/kotlin/dev/inmo/krontab/builder/SchedulerBuilder.kt

@@ -21,20 +21,21 @@ class SchedulerBuilder(
     private var minutes: Array<Byte>? = null,
     private var hours: Array<Byte>? = null,
     private var dayOfMonth: Array<Byte>? = null,
-    private var month: Array<Byte>? = null
+    private var month: Array<Byte>? = null,
+    private var year: Array<Int>? = null
 ) {
-    private fun <T : TimeBuilder> callAndReturn(
-        initial: Array<Byte>?,
+    private fun <I, T : TimeBuilder<I>> callAndReturn(
+        initial: Array<I>?,
         builder: T,
         block: T.() -> Unit
-    ): Array<Byte>? {
+    ): List<I>? {
         builder.block()
 
         val builderValue = builder.build()
 
         return initial ?.let {
             builderValue ?.let { _ ->
-                (it + builderValue).distinct().toTypedArray()
+                (it + builderValue).distinct()
             } ?: builderValue
         } ?: builderValue
     }
@@ -47,7 +48,7 @@ class SchedulerBuilder(
             seconds,
             SecondsBuilder(),
             block
-        )
+        ) ?.toTypedArray()
     }
 
     /**
@@ -58,7 +59,7 @@ class SchedulerBuilder(
             minutes,
             MinutesBuilder(),
             block
-        )
+        ) ?.toTypedArray()
     }
 
     /**
@@ -69,7 +70,7 @@ class SchedulerBuilder(
             hours,
             HoursBuilder(),
             block
-        )
+        ) ?.toTypedArray()
     }
 
     /**
@@ -80,7 +81,7 @@ class SchedulerBuilder(
             dayOfMonth,
             DaysOfMonthBuilder(),
             block
-        )
+        ) ?.toTypedArray()
     }
 
     /**
@@ -91,7 +92,18 @@ class SchedulerBuilder(
             month,
             MonthsBuilder(),
             block
-        )
+        ) ?.toTypedArray()
+    }
+
+    /**
+     * Starts an year block
+     */
+    fun years(block: YearsBuilder.() -> Unit) {
+        year = callAndReturn(
+            year,
+            YearsBuilder(),
+            block
+        ) ?.toTypedArray()
     }
 
     /**
@@ -100,5 +112,5 @@ class SchedulerBuilder(
      * @see dev.inmo.krontab.createSimpleScheduler
      * @see dev.inmo.krontab.internal.createKronScheduler
      */
-    fun build(): KronScheduler = createKronScheduler(seconds, minutes, hours, dayOfMonth, month)
+    fun build(): KronScheduler = createKronScheduler(seconds, minutes, hours, dayOfMonth, month, year)
 }

src/commonMain/kotlin/dev/inmo/krontab/builder/TimeBuilder.kt

@@ -7,8 +7,9 @@ import dev.inmo.krontab.utils.clamp
  * This class was created for incapsulation of builder work with specified [restrictionsRange]. For example,
  * [include] function of [TimeBuilder] will always [clamp] incoming data using its [restrictionsRange]
  */
-sealed class TimeBuilder (
-    private val restrictionsRange: IntRange
+sealed class TimeBuilder<T : Number> (
+    private val restrictionsRange: IntRange,
+    private val converter: Converter<T>
 ) {
     private var result: Set<Int>? = null
 
@@ -119,11 +120,12 @@ sealed class TimeBuilder (
      */
     fun includeFirst() = at(restrictionsRange.first)
 
-    internal fun build() = result ?.map { it.toByte() } ?.toTypedArray()
+    internal fun build() = result ?.map(converter)
 }
 
-class SecondsBuilder : TimeBuilder(secondsRange)
-class MinutesBuilder : TimeBuilder(minutesRange)
-class HoursBuilder : TimeBuilder(hoursRange)
-class DaysOfMonthBuilder : TimeBuilder(dayOfMonthRange)
-class MonthsBuilder : TimeBuilder(monthRange)
+class SecondsBuilder : TimeBuilder<Byte>(secondsRange, intToByteConverter)
+class MinutesBuilder : TimeBuilder<Byte>(minutesRange, intToByteConverter)
+class HoursBuilder : TimeBuilder<Byte>(hoursRange, intToByteConverter)
+class DaysOfMonthBuilder : TimeBuilder<Byte>(dayOfMonthRange, intToByteConverter)
+class MonthsBuilder : TimeBuilder<Byte>(monthRange, intToByteConverter)
+class YearsBuilder : TimeBuilder<Int>(yearRange, intToIntConverter)

src/commonMain/kotlin/dev/inmo/krontab/collection/CollectionKronScheduler.kt

@@ -1,11 +1,9 @@
 package dev.inmo.krontab.collection
 
 import com.soywiz.klock.DateTime
-import dev.inmo.krontab.KronScheduler
-import dev.inmo.krontab.anyCronDateTime
+import dev.inmo.krontab.*
 import dev.inmo.krontab.internal.*
 import dev.inmo.krontab.internal.CronDateTimeScheduler
-import dev.inmo.krontab.internal.merge
 import dev.inmo.krontab.internal.toNearDateTime
 
 /**
@@ -20,7 +18,7 @@ data class CollectionKronScheduler internal constructor(
      * Add [kronScheduler] into its [schedulers] list
      *
      * * When [kronScheduler] is [CronDateTimeScheduler] it will merge all [CronDateTimeScheduler]s from [schedulers] list
-     * and this [kronScheduler] using [merge] function
+     * and this [kronScheduler] using [mergeCronDateTimeSchedulers] function
      * * When [kronScheduler] is [CollectionKronScheduler] it this instance will include all [kronScheduler]
      * [schedulers]
      * * Otherwise [kronScheduler] will be added to [schedulers] list
@@ -37,7 +35,7 @@ data class CollectionKronScheduler internal constructor(
                     }
                 }
                 schedulers.add(
-                    merge(resultCronDateTimes)
+                    mergeCronDateTimeSchedulers(resultCronDateTimes)
                 )
             }
             is CollectionKronScheduler -> kronScheduler.schedulers.forEach {
@@ -48,6 +46,6 @@ data class CollectionKronScheduler internal constructor(
     }
 
     override suspend fun next(relatively: DateTime): DateTime {
-        return schedulers.minOfOrNull { it.next(relatively) } ?: anyCronDateTime.toNearDateTime(relatively)
+        return schedulers.mapNotNull { it.next(relatively) }.minOrNull() ?: getAnyNext(relatively)
     }
 }

src/commonMain/kotlin/dev/inmo/krontab/internal/CronDateTime.kt

@@ -12,6 +12,7 @@ import dev.inmo.krontab.KronScheduler
  * @param seconds 0-59
  */
 internal data class CronDateTime(
+    val year: Int? = null,
     val month: Byte? = null,
     val dayOfMonth: Byte? = null,
     val hours: Byte? = null,
@@ -19,6 +20,7 @@ internal data class CronDateTime(
     val seconds: Byte? = null
 ) {
     init {
+        check(year ?.let { it in yearRange } ?: true)
         check(month ?.let { it in monthRange } ?: true)
         check(dayOfMonth ?.let { it in dayOfMonthRange } ?: true)
         check(hours?.let { it in hoursRange } ?: true)
@@ -32,7 +34,7 @@ internal data class CronDateTime(
 /**
  * @return The near [DateTime] which happens after [relativelyTo] or will be equal to [relativelyTo]
  */
-internal fun CronDateTime.toNearDateTime(relativelyTo: DateTime = DateTime.now()): DateTime {
+internal fun CronDateTime.toNearDateTime(relativelyTo: DateTime = DateTime.now()): DateTime? {
     var current = relativelyTo
 
     seconds?.let {
@@ -63,7 +65,13 @@ internal fun CronDateTime.toNearDateTime(relativelyTo: DateTime = DateTime.now()
 
     month ?.let {
         val left = it - current.month0
-        current += DateTimeSpan(months = if (left < 0) 1 else 0, days = left)
+        current += DateTimeSpan(years = if (left < 0) 1 else 0, months = left)
+    }
+
+    year ?.let {
+        if (current.yearInt != it) {
+            return null
+        }
     }
 
     return current
@@ -77,7 +85,8 @@ internal fun createKronScheduler(
     minutes: Array<Byte>? = null,
     hours: Array<Byte>? = null,
     dayOfMonth: Array<Byte>? = null,
-    month: Array<Byte>? = null
+    month: Array<Byte>? = null,
+    years: Array<Int>? = null
 ): KronScheduler {
     val resultCronDateTimes = mutableListOf(CronDateTime())
 
@@ -101,5 +110,9 @@ internal fun createKronScheduler(
         previousCronDateTime.copy(month = currentTime)
     }
 
+    years ?.fillWith(resultCronDateTimes) { previousCronDateTime: CronDateTime, currentTime: Int ->
+        previousCronDateTime.copy(year = currentTime)
+    }
+
     return CronDateTimeScheduler(resultCronDateTimes.toList())
 }

src/commonMain/kotlin/dev/inmo/krontab/internal/CronDateTimeScheduler.kt

@@ -1,8 +1,8 @@
 package dev.inmo.krontab.internal
 
 import com.soywiz.klock.DateTime
-import dev.inmo.krontab.KronScheduler
-import dev.inmo.krontab.anyCronDateTime
+import dev.inmo.krontab.*
+import dev.inmo.krontab.collection.plus
 
 /**
  * Cron-oriented realisation of [KronScheduler]
@@ -13,40 +13,44 @@ import dev.inmo.krontab.anyCronDateTime
  * @see dev.inmo.krontab.EveryHourScheduler
  * @see dev.inmo.krontab.EveryDayOfMonthScheduler
  * @see dev.inmo.krontab.EveryMonthScheduler
+ * @see dev.inmo.krontab.EveryYearScheduler
  *
  * @see dev.inmo.krontab.builder.buildSchedule
  * @see dev.inmo.krontab.builder.SchedulerBuilder
  */
-@Deprecated("This class will get internal status in future")
-data class CronDateTimeScheduler internal constructor(
+internal data class CronDateTimeScheduler internal constructor(
     internal val cronDateTimes: List<CronDateTime>
 ) : KronScheduler {
     /**
-     * @return Near date using [cronDateTimes] list and getting the [Iterable.min] one
+     * @return Near date using [cronDateTimes] list and getting the [Iterable.minByOrNull] one
      *
      * @see toNearDateTime
      */
     override suspend fun next(relatively: DateTime): DateTime {
-        return cronDateTimes.map { it.toNearDateTime(relatively) }.minOrNull() ?: anyCronDateTime.toNearDateTime(relatively)
+        return cronDateTimes.mapNotNull { it.toNearDateTime(relatively) }.minOrNull() ?: getAnyNext(relatively)
     }
 }
 
-/**
- * @return New instance of [CronDateTimeScheduler] with all unique [CronDateTimeScheduler.cronDateTimes] of
- * [kronDateTimeSchedulers] included
- */
-@Suppress("NOTHING_TO_INLINE")
-fun merge(kronDateTimeSchedulers: List<CronDateTimeScheduler>) = CronDateTimeScheduler(
-    kronDateTimeSchedulers.flatMap { it.cronDateTimes }.distinct()
+internal fun mergeCronDateTimeSchedulers(schedulers: List<CronDateTimeScheduler>) = CronDateTimeScheduler(
+    schedulers.flatMap { it.cronDateTimes }
 )
 
 /**
- * @return Vararg shortcyut for [merge]
+ * @return New instance of [CronDateTimeScheduler] with all unique [CronDateTimeScheduler.cronDateTimes] of
+ * [kronSchedulers] included
  */
-@Suppress("NOTHING_TO_INLINE")
-inline fun merge(vararg kronDateTimeSchedulers: CronDateTimeScheduler) = merge(kronDateTimeSchedulers.toList())
+@Deprecated("Will be removed in next major release", ReplaceWith("merge", "dev.inmo.krontab"))
+fun merge(kronSchedulers: List<KronScheduler>) = kronSchedulers.apply { dev.inmo.krontab.merge() }
+
 /**
- * Use [merge] operation to internalcreate new [CronDateTimeScheduler] with all [CronDateTimeScheduler.cronDateTimes]
+ * @return Vararg shortcut for [dev.inmo.krontab.merge]
  */
 @Suppress("NOTHING_TO_INLINE")
-inline fun CronDateTimeScheduler.plus(other: CronDateTimeScheduler) = merge(this, other)
+@Deprecated("Will be removed in next major release", ReplaceWith("merge", "dev.inmo.krontab"))
+inline fun merge(vararg kronDateTimeSchedulers: KronScheduler) = kronDateTimeSchedulers.apply { dev.inmo.krontab.merge() }
+/**
+ * @return Vararg shortcut for [dev.inmo.krontab.merge]
+ */
+@Suppress("NOTHING_TO_INLINE")
+@Deprecated("Will be removed in next major release", ReplaceWith("merge", "dev.inmo.krontab"))
+inline fun KronScheduler.plus(other: KronScheduler) = this + other

src/commonMain/kotlin/dev/inmo/krontab/internal/Parser.kt

@@ -2,7 +2,11 @@ package dev.inmo.krontab.internal
 
 import dev.inmo.krontab.utils.clamp
 
-private fun createSimpleScheduler(from: String, dataRange: IntRange): Array<Byte>? {
+typealias Converter<T> = (Int) -> T
+
+internal val intToByteConverter: Converter<Byte> = { it: Int -> it.toByte() }
+internal val intToIntConverter: Converter<Int> = { it: Int -> it }
+private fun <T> createSimpleScheduler(from: String, dataRange: IntRange, dataConverter: Converter<T>): List<T>? {
     val things = from.split(",")
 
     val results = things.flatMap {
@@ -31,18 +35,19 @@ private fun createSimpleScheduler(from: String, dataRange: IntRange): Array<Byte
         }
     }
 
-    return results.map { it.toByte() }.toTypedArray()
+    return results.map(dataConverter)
 }
 
-internal fun parseMonths(from: String) = createSimpleScheduler(from, monthRange)
-internal fun parseDaysOfMonth(from: String) = createSimpleScheduler(from, dayOfMonthRange)
-internal fun parseHours(from: String) = createSimpleScheduler(from, hoursRange)
-internal fun parseMinutes(from: String) = createSimpleScheduler(from, minutesRange)
-internal fun parseSeconds(from: String) = createSimpleScheduler(from, secondsRange)
+internal fun parseYears(from: String?) = from ?.let { createSimpleScheduler(from, yearRange, intToIntConverter) ?.toTypedArray() }
+internal fun parseMonths(from: String) = createSimpleScheduler(from, monthRange, intToByteConverter) ?.toTypedArray()
+internal fun parseDaysOfMonth(from: String) = createSimpleScheduler(from, dayOfMonthRange, intToByteConverter) ?.toTypedArray()
+internal fun parseHours(from: String) = createSimpleScheduler(from, hoursRange, intToByteConverter) ?.toTypedArray()
+internal fun parseMinutes(from: String) = createSimpleScheduler(from, minutesRange, intToByteConverter) ?.toTypedArray()
+internal fun parseSeconds(from: String) = createSimpleScheduler(from, secondsRange, intToByteConverter) ?.toTypedArray()
 
-internal fun Array<Byte>.fillWith(
+internal fun <T> Array<T>.fillWith(
     whereToPut: MutableList<CronDateTime>,
-    createFactory: (CronDateTime, Byte) -> CronDateTime
+    createFactory: (CronDateTime, T) -> CronDateTime
 ) {
     val previousValues = whereToPut.toList()
 

src/commonMain/kotlin/dev/inmo/krontab/internal/Ranges.kt

@@ -1,5 +1,6 @@
 package dev.inmo.krontab.internal
 
+internal val yearRange = Int.MIN_VALUE .. Int.MAX_VALUE
 internal val monthRange = 0 .. 11
 internal val dayOfMonthRange = 0 .. 30
 internal val hoursRange = 0 .. 23

src/commonMain/kotlin/dev/inmo/krontab/utils/SchedulerFlow.kt

@@ -17,7 +17,7 @@ class SchedulerFlow(
     override suspend fun collectSafely(collector: FlowCollector<DateTime>) {
         while (true) {
             val now = DateTime.now()
-            val nextTime = scheduler.next(now)
+            val nextTime = scheduler.next(now) ?: break
             val sleepDelay = (nextTime - now).millisecondsLong
             delay(sleepDelay)
             collector.emit(nextTime)

src/main/AndroidManifest.xml

@@ -0,0 +1 @@
+<manifest package="dev.inmo.krontab"/>

src/main/kotlin/dev/inmo/krontab/KronSchedulerWork.kt

@@ -0,0 +1,147 @@
+package dev.inmo.krontab
+
+import android.content.Context
+import androidx.work.*
+import com.soywiz.klock.DateTime
+import java.util.concurrent.TimeUnit
+
+/**
+ * This method will enqueue [OneTimeWorkRequest] with [workName] and [existingWorkPolicy]. Use [setUpRequest] callback
+ * in case you need some additional actions to do before request will be enqueued
+ */
+suspend fun <T : KronSchedulerWork> Context.enqueueKronSchedulerWork(
+    workName: String,
+    delayMillis: Long,
+    workClass: Class<T>,
+    existingWorkPolicy: ExistingWorkPolicy = ExistingWorkPolicy.REPLACE,
+    setUpRequest: suspend OneTimeWorkRequest.Builder.() -> Unit = {}
+) = WorkManager.getInstance(applicationContext).enqueueUniqueWork(
+    workName,
+    existingWorkPolicy,
+    OneTimeWorkRequest.Builder(workClass).apply {
+        setInitialDelay(delayMillis, TimeUnit.MILLISECONDS)
+        setUpRequest()
+    }.build()
+)
+/**
+ * This method is shortcut for [enqueueKronSchedulerWork] with reified [T] parameter
+ */
+suspend inline fun <reified T : KronSchedulerWork> Context.enqueueKronSchedulerWork(
+    workName: String,
+    delayMillis: Long,
+    existingWorkPolicy: ExistingWorkPolicy = ExistingWorkPolicy.REPLACE,
+    noinline setUpRequest: suspend OneTimeWorkRequest.Builder.() -> Unit = {}
+) = enqueueKronSchedulerWork(workName, delayMillis, T::class.java, existingWorkPolicy, setUpRequest)
+
+/**
+ * This method is shortcut for [enqueueKronSchedulerWork] with [initialScheduler]. It will try to calculate delay by
+ * itself. In case if [KronScheduler.next] of [initialScheduler] will return null, work WILL NOT be enqueued
+ *
+ * @return null in case if [KronScheduler.next] of [initialScheduler] has returned null and work has not been enqueued
+ */
+suspend fun <T : KronSchedulerWork> Context.enqueueKronSchedulerWork(
+    workName: String,
+    initialScheduler: KronScheduler,
+    workClass: Class<T>,
+    existingWorkPolicy: ExistingWorkPolicy = ExistingWorkPolicy.REPLACE,
+    setUpRequest: suspend OneTimeWorkRequest.Builder.() -> Unit = {}
+): Operation? {
+    val now = DateTime.now()
+    val nextTriggerTime = initialScheduler.next(now)
+    val delayMillis = nextTriggerTime ?.minus(now) ?.millisecondsLong ?: return null
+
+    return enqueueKronSchedulerWork(workName, delayMillis, workClass, existingWorkPolicy, setUpRequest)
+}
+/**
+ * This method is shortcut for [enqueueKronSchedulerWork] with reified [T]
+ */
+suspend inline fun <reified T : KronSchedulerWork> Context.enqueueKronSchedulerWork(
+    workName: String,
+    initialScheduler: KronScheduler,
+    existingWorkPolicy: ExistingWorkPolicy = ExistingWorkPolicy.REPLACE,
+    noinline setUpRequest: suspend OneTimeWorkRequest.Builder.() -> Unit = {}
+) = enqueueKronSchedulerWork(workName, initialScheduler, T::class.java, existingWorkPolicy, setUpRequest)
+
+/**
+ * Use this class as a super class in case you wish to implement krontab-based enqueuing of works
+ *
+ * @see enqueueKronSchedulerWork
+ * @see KrontabTemplateSchedulerWork
+ */
+abstract class KronSchedulerWork(
+    context: Context,
+    workerParams: WorkerParameters
+) : CoroutineWorker(
+    context,
+    workerParams
+) {
+    /**
+     * This variable will be used to reorder new work after that one is happen
+     *
+     * @see prolongOnException
+     * @see prolongOnFailure
+     * @see prolongOnSuccess
+     */
+    protected abstract val workName: String
+
+    /**
+     * Set this to false in case when this work must not be enqueued after successful complete
+     */
+    protected open val prolongOnSuccess: Boolean = true
+    /**
+     * Set this to false in case when this work must not be enqueued after failure complete
+     */
+    protected open val prolongOnFailure
+        get() = prolongOnSuccess
+    /**
+     * Set this to false in case when this work must not be enqueued after exception happen
+     */
+    protected open val prolongOnException = false
+
+    /**
+     * [KronScheduler] of this method will be used to [prolong] this worker
+     */
+    protected abstract suspend fun kronScheduler(): KronScheduler?
+
+    /**
+     * This method is replacement of [doWork]. It is required to wrap work with [prolong]ing and handling of complete
+     * state
+     */
+    protected abstract suspend fun onWork(): Result
+
+    /**
+     * Override this method in case you have some additional settings for future [OneTimeWorkRequest]
+     */
+    protected open suspend fun OneTimeWorkRequest.Builder.setUpRequest() {}
+
+    /**
+     * This method will [enqueueKronSchedulerWork] using [workName], [kronScheduler] and default
+     * [ExistingWorkPolicy.REPLACE]. You can call this method in case you want to enqueue work by yourself, but you must
+     * be sure that you set up to false [prolongOnSuccess], [prolongOnFailure] and [prolongOnException]
+     */
+    protected suspend fun prolong() {
+        applicationContext.enqueueKronSchedulerWork(
+            workName,
+            kronScheduler() ?: return,
+            this::class.java
+        ) {
+            setUpRequest()
+        }
+    }
+
+    override suspend fun doWork(): Result {
+        val result = try {
+            onWork()
+        } catch (e: Throwable) {
+            if (prolongOnException) {
+                prolong()
+            }
+            throw e
+        }
+        when (result) {
+            is Result.Failure -> if (prolongOnFailure) prolong()
+            is Result.Success -> if (prolongOnSuccess) prolong()
+        }
+        return result
+    }
+}

src/main/kotlin/dev/inmo/krontab/KrontabTemplateSchedulerWork.kt

@@ -0,0 +1,68 @@
+package dev.inmo.krontab
+
+import android.content.Context
+import androidx.work.*
+
+const val krontabTemplateWorkField = "krontabTemplate"
+
+/**
+ * Will [enqueueKronSchedulerWork] with [KronScheduler] from [krontabTemplate] and call [setUpRequest] on setting up
+ * [OneTimeWorkRequest.Builder] with [Data] which will be used to [OneTimeWorkRequest.Builder.setInputData] after
+ * [setUpRequest] completed
+ */
+suspend inline fun <reified T : KrontabTemplateSchedulerWork> Context.enqueueKrontabTemplateSchedulerWork(
+    workName: String,
+    krontabTemplate: KrontabTemplate,
+    existingWorkPolicy: ExistingWorkPolicy = ExistingWorkPolicy.REPLACE,
+    noinline setUpRequest: suspend OneTimeWorkRequest.Builder.(
+        data: Data
+    ) -> Unit = {}
+) = enqueueKronSchedulerWork(workName, krontabTemplate.toKronScheduler(), T::class.java, existingWorkPolicy) {
+    val data = workDataOf(
+        krontabTemplateWorkField to krontabTemplate
+    )
+    setUpRequest(data)
+    setInputData(data)
+}
+
+/**
+ * Extend this class in case you wish to base on [KrontabTemplate]. It will automatically handle request of
+ * [kronScheduler] and put it in [setUpRequest]
+ */
+abstract class KrontabTemplateSchedulerWork(
+    context: Context,
+    workerParams: WorkerParameters
+) : KronSchedulerWork(context, workerParams) {
+    /**
+     * Will try to get [KrontabTemplate] from [getInputData] by key [krontabTemplateWorkField]
+     *
+     * @see setUpRequest
+     */
+    protected val krontabTemplate: KrontabTemplate?
+        get() = inputData.getString(krontabTemplateWorkField)
+
+    /**
+     * Override this methods instead of old [setUpRequest] in case you wish to set up some work request parameters
+     *
+     * @param data This parameter will be used to put data inside of [OneTimeWorkRequest.Builder] after this method
+     * will be completed
+     */
+    protected open suspend fun OneTimeWorkRequest.Builder.setUpRequest(data: Data) {}
+
+    /**
+     * Will automatically put [krontabTemplate] into work data, call [setUpRequest] with future [Data] object and then
+     * call [OneTimeWorkRequest.Builder.setInputData] with that [Data] object
+     */
+    override suspend fun OneTimeWorkRequest.Builder.setUpRequest() {
+        val data = workDataOf(
+            krontabTemplateWorkField to krontabTemplate,
+        )
+        setUpRequest(data)
+        setInputData(data)
+    }
+
+    /**
+     * Will return [KronScheduler] in case if [krontabTemplate] was not null
+     */
+    override suspend fun kronScheduler(): KronScheduler? = krontabTemplate ?.toKronScheduler()
+}