com.fireflysource.net.http.common.content.handler.AbstractFileContentHandler.kt Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of firefly-net Show documentation
There is a newer version: 5.0.2
package com.fireflysource.net.http.common.content.handler

import com.fireflysource.common.coroutine.asVoidFuture
import com.fireflysource.common.coroutine.event
import com.fireflysource.common.io.closeJob
import com.fireflysource.common.io.openFileChannelAsync
import com.fireflysource.common.io.writeAwait
import com.fireflysource.common.sys.SystemLogger
import kotlinx.coroutines.Job
import kotlinx.coroutines.channels.Channel
import java.nio.ByteBuffer
import java.nio.file.OpenOption
import java.nio.file.Path
import java.util.concurrent.CompletableFuture

abstract class AbstractFileContentHandler(val path: Path, vararg options: OpenOption) : HttpContentHandler {

    companion object {
        private val log = SystemLogger.create(AbstractFileContentHandler::class.java)
    }

    private val inputChannel: Channel = Channel(Channel.UNLIMITED)
    private val writeJob: Job

    init {
        writeJob = event {
            val fileChannel = openFileChannelAsync(path, *options).await()
            var pos = 0L

            suspend fun closeFileChannel() {
                try {
                    fileChannel.closeJob().join()
                } catch (e: Exception) {
                    log.error(e) { "close file channel exception." }
                }
            }

            suspend fun read(): Boolean {
                var closed = false
                when (val writeFileMessage = inputChannel.receive()) {
                    is WriteFileRequest -> {
                        val buf = writeFileMessage.buffer
                        flushDataLoop@ while (buf.hasRemaining()) {
                            val len = fileChannel.writeAwait(buf, pos)
                            if (len < 0) {
                                closeFileChannel()
                                closed = true
                            }
                            pos += len
                        }
                    }
                    is EndWriteFile -> {
                        closeFileChannel()
                        closed = true
                    }
                }
                return closed
            }

            writeMessageLoop@ while (true) {
                val closed = try {
                    read()
                } catch (e: Exception) {
                    log.error(e) { "read file exception." }
                    closeFileChannel()
                    true
                }
                if (closed) break@writeMessageLoop
            }
        }
    }


    override fun accept(buffer: ByteBuffer, t: T) {
        inputChannel.offer(WriteFileRequest(buffer))
    }

    override fun closeAsync(): CompletableFuture = event { closeAwait() }.asVoidFuture()

    override fun close() {
        inputChannel.offer(EndWriteFile)
    }

    private suspend fun closeAwait() {
        close()
        writeJob.join()
    }

}

sealed class WriteFileMessage
class WriteFileRequest(val buffer: ByteBuffer) : WriteFileMessage()
object EndWriteFile : WriteFileMessage()