68 lines
1.8 KiB
Go
68 lines
1.8 KiB
Go
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package compression
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import (
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"bytes"
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"crypto/rand"
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"io/ioutil"
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"testing"
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)
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// generateData generates data that composed of 2 random parts
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// and single zero-filled part within them.
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// Typically, the compression ratio would be about 67%.
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func generateData(t *testing.T, size int) []byte {
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part0 := size / 3 // random
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part2 := size / 3 // random
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part1 := size - part0 - part2 // zero-filled
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part0Data := make([]byte, part0)
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if _, err := rand.Read(part0Data); err != nil {
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t.Fatal(err)
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}
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part1Data := make([]byte, part1)
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part2Data := make([]byte, part2)
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if _, err := rand.Read(part2Data); err != nil {
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t.Fatal(err)
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}
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return append(part0Data, append(part1Data, part2Data...)...)
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}
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func testCompressDecompress(t *testing.T, size int, compression Compression) {
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orig := generateData(t, size)
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var b bytes.Buffer
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compressor, err := CompressStream(&b, compression)
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if err != nil {
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t.Fatal(err)
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}
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if n, err := compressor.Write(orig); err != nil || n != size {
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t.Fatal(err)
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}
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compressor.Close()
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compressed := b.Bytes()
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t.Logf("compressed %d bytes to %d bytes (%.2f%%)",
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len(orig), len(compressed), 100.0*float32(len(compressed))/float32(len(orig)))
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if compared := bytes.Compare(orig, compressed); (compression == Uncompressed && compared != 0) ||
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(compression != Uncompressed && compared == 0) {
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t.Fatal("strange compressed data")
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}
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decompressor, err := DecompressStream(bytes.NewReader(compressed))
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if err != nil {
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t.Fatal(err)
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}
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decompressed, err := ioutil.ReadAll(decompressor)
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if err != nil {
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t.Fatal(err)
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}
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if bytes.Compare(orig, decompressed) != 0 {
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t.Fatal("strange decompressed data")
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}
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}
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func TestCompressDecompressGzip(t *testing.T) {
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testCompressDecompress(t, 1024*1024, Gzip)
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}
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func TestCompressDecompressUncompressed(t *testing.T) {
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testCompressDecompress(t, 1024*1024, Uncompressed)
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}
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