(Go) Unzip Binary File to Stream

Demonstrates how to unzip a large binary file to a stream to allow the application to process the uncompressed bytes chunk by chunk.

Note: This example requires Chilkat v9.5.0.67 or greater.

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    // This requires the Chilkat Zip API to have been previously unlocked.
    // See Unlock Chilkat Zip for sample code.

    zip := chilkat.NewZip()

    // First open a .zip.
    success := zip.OpenZip("qa_data/zips/big.zip")
    if success != true {
        fmt.Println(zip.LastErrorText())
        zip.DisposeZip()
        return
    }

    // Get the entry to be unzipped to a stream..
    entry := zip.GetEntryByIndex(0)
    if zip.LastMethodSuccess() != true {
        fmt.Println(zip.LastErrorText())
        zip.DisposeZip()
        return
    }

    dataStream := chilkat.NewStream()

    c := make(chan *chilkat.Task)
    go entry.UnzipToStreamAsync(dataStream,c)
    unzipTask := <-c
    if entry.LastMethodSuccess() != true {
        fmt.Println(entry.LastErrorText())
        entry.DisposeZipEntry()
        zip.DisposeZip()
        dataStream.DisposeStream()
        unzipTask.DisposeTask()
        return
    }

    // Start the background unzip thread.

    // We'll read the uncompressed data chunk-by-chunk and write to an output file.
    fac := chilkat.NewFileAccess()
    success = fac.OpenForWrite("qa_output/out.dat")
    if success != true {
        fmt.Println(fac.LastErrorText())
        entry.DisposeZipEntry()
        zip.DisposeZip()
        dataStream.DisposeStream()
        unzipTask.DisposeTask()
        fac.DisposeFileAccess()
        return
    }

    // Read the stream.  (this is reading the unzipped file data)
    bd := chilkat.NewBinData()
    for dataStream.EndOfStream() != true {
        // Get the next chunk of decompressed bytes.
        dataStream.ReadBd(bd)
        // Do something with it..
        // In this simple example, we'll just write to the file.
        fac.FileWriteBd(bd,0,0)
        // Clear for the next read.
        bd.Clear()
    }

    fac.FileClose()

    entry.DisposeZipEntry()
    unzipTask.DisposeTask()
    fmt.Println("Success.")

    zip.DisposeZip()
    dataStream.DisposeStream()
    unzipTask.DisposeTask()
    fac.DisposeFileAccess()
    bd.DisposeBinData()