r.0.9.1.source-code.FanoutChannel.kt Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of tolr Show documentation
tolr
The newest version!
package se.wollan.tolr

import kotlinx.coroutines.channels.BufferOverflow
import kotlinx.coroutines.channels.Channel
import kotlinx.coroutines.channels.ReceiveChannel

internal interface FanoutReceiveChannel {
    fun startReceiving(filter: RecordTypePattern): ReceiveChannel
    fun stopReceiving(channel: ReceiveChannel)
}

internal interface FanoutSendChannel {
    suspend fun send(record: LogRecord)
    suspend fun send(records: Collection)
}

internal class FanoutChannel(private val capacity: Int = 100) : FanoutReceiveChannel, FanoutSendChannel {
    private val receivers = mutableSetOf, RecordTypePattern>>()

    override fun startReceiving(filter: RecordTypePattern): ReceiveChannel {
        val channel = Channel(capacity = capacity, onBufferOverflow = BufferOverflow.SUSPEND)
        synchronized(receivers) {
            receivers.add(channel to filter)
        }
        return channel
    }

    override fun stopReceiving(channel: ReceiveChannel) {
        synchronized(receivers) {
            receivers.removeAll { it.first === channel }
        }
        channel.cancel()
    }

    override suspend fun send(record: LogRecord) {
        val receivers = synchronized(receivers) {
            receivers.toSet()
        }

        if (receivers.isEmpty())
            return

        fanout(receivers, record)
    }

    override suspend fun send(records: Collection) {
        if (records.isEmpty())
            return

        val receivers = synchronized(receivers) {
            receivers.toSet()
        }

        if (receivers.isEmpty())
            return

        for (record in records) {
            fanout(receivers, record)
        }
    }

    private suspend fun fanout(
        receivers: Set, RecordTypePattern>>,
        record: LogRecord
    ) {
        for ((channel, filter) in receivers) {
            if (filter.matches(record.type))
                channel.send(record)
        }
    }
}