1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
|
/*
* Copyright 2016-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
*/
@file:Suppress("INVISIBLE_REFERENCE", "INVISIBLE_MEMBER")
package kotlinx.coroutines.reactor
import kotlinx.coroutines.*
import reactor.core.*
import reactor.core.publisher.*
import kotlin.coroutines.*
import kotlin.internal.*
/**
* Creates cold [mono][Mono] that will run a given [block] in a coroutine and emits its result.
* Every time the returned mono is subscribed, it starts a new coroutine.
* If [block] result is `null`, [MonoSink.success] is invoked without a value.
* Unsubscribing cancels running coroutine.
*
* Coroutine context can be specified with [context] argument.
* If the context does not have any dispatcher nor any other [ContinuationInterceptor], then [Dispatchers.Default] is used.
*
* Method throws [IllegalArgumentException] if provided [context] contains a [Job] instance.
*/
public fun <T> mono(
context: CoroutineContext = EmptyCoroutineContext,
block: suspend CoroutineScope.() -> T?
): Mono<T> {
require(context[Job] === null) { "Mono context cannot contain job in it." +
"Its lifecycle should be managed via Disposable handle. Had $context" }
return monoInternal(GlobalScope, context, block)
}
@Deprecated(
message = "CoroutineScope.mono is deprecated in favour of top-level mono",
level = DeprecationLevel.ERROR,
replaceWith = ReplaceWith("mono(context, block)")
) // Since 1.3.0, will be error in 1.3.1 and hidden in 1.4.0
@LowPriorityInOverloadResolution
public fun <T> CoroutineScope.mono(
context: CoroutineContext = EmptyCoroutineContext,
block: suspend CoroutineScope.() -> T?
): Mono<T> = monoInternal(this, context, block)
private fun <T> monoInternal(
scope: CoroutineScope, // support for legacy mono in scope
context: CoroutineContext,
block: suspend CoroutineScope.() -> T?
): Mono<T> = Mono.create { sink ->
val reactorContext = (context[ReactorContext]?.context?.putAll(sink.currentContext()) ?: sink.currentContext()).asCoroutineContext()
val newContext = scope.newCoroutineContext(context + reactorContext)
val coroutine = MonoCoroutine(newContext, sink)
sink.onDispose(coroutine)
coroutine.start(CoroutineStart.DEFAULT, coroutine, block)
}
private class MonoCoroutine<in T>(
parentContext: CoroutineContext,
private val sink: MonoSink<T>
) : AbstractCoroutine<T>(parentContext, true), Disposable {
@Volatile
private var disposed = false
override fun onCompleted(value: T) {
if (value == null) sink.success() else sink.success(value)
}
override fun onCancelled(cause: Throwable, handled: Boolean) {
try {
/*
* sink.error handles exceptions on its own and, by default, handling of undeliverable exceptions is a no-op.
* Guard potentially non-empty handlers against meaningless cancellation exceptions
*/
if (getCancellationException() !== cause) {
sink.error(cause)
}
} catch (e: Throwable) {
// In case of improper error implementation or fatal exceptions
handleCoroutineException(context, cause)
}
}
override fun dispose() {
disposed = true
cancel()
}
override fun isDisposed(): Boolean = disposed
}
|
