github.com/peterbourgon/diskv@v2.0.1+incompatible/compression_test.go (about)

     1  package diskv
     2  
     3  import (
     4  	"compress/flate"
     5  	"fmt"
     6  	"math/rand"
     7  	"os"
     8  	"testing"
     9  	"time"
    10  )
    11  
    12  func init() {
    13  	rand.Seed(time.Now().UnixNano())
    14  }
    15  
    16  func testCompressionWith(t *testing.T, c Compression, name string) {
    17  	d := New(Options{
    18  		BasePath:     "compression-test",
    19  		CacheSizeMax: 0,
    20  		Compression:  c,
    21  	})
    22  	defer d.EraseAll()
    23  
    24  	sz := 4096
    25  	val := make([]byte, sz)
    26  	for i := 0; i < sz; i++ {
    27  		val[i] = byte('a' + rand.Intn(26)) // {a-z}; should compress some
    28  	}
    29  
    30  	key := "a"
    31  	if err := d.Write(key, val); err != nil {
    32  		t.Fatalf("write failed: %s", err)
    33  	}
    34  
    35  	targetFile := fmt.Sprintf("%s%c%s", d.BasePath, os.PathSeparator, key)
    36  	fi, err := os.Stat(targetFile)
    37  	if err != nil {
    38  		t.Fatalf("%s: %s", targetFile, err)
    39  	}
    40  
    41  	if fi.Size() >= int64(sz) {
    42  		t.Fatalf("%s: size=%d, expected smaller", targetFile, fi.Size())
    43  	}
    44  	t.Logf("%s compressed %d to %d", name, sz, fi.Size())
    45  
    46  	readVal, err := d.Read(key)
    47  	if len(readVal) != sz {
    48  		t.Fatalf("read: expected size=%d, got size=%d", sz, len(readVal))
    49  	}
    50  
    51  	for i := 0; i < sz; i++ {
    52  		if readVal[i] != val[i] {
    53  			t.Fatalf("i=%d: expected %v, got %v", i, val[i], readVal[i])
    54  		}
    55  	}
    56  }
    57  
    58  func TestGzipDefault(t *testing.T) {
    59  	testCompressionWith(t, NewGzipCompression(), "gzip")
    60  }
    61  
    62  func TestGzipBestCompression(t *testing.T) {
    63  	testCompressionWith(t, NewGzipCompressionLevel(flate.BestCompression), "gzip-max")
    64  }
    65  
    66  func TestGzipBestSpeed(t *testing.T) {
    67  	testCompressionWith(t, NewGzipCompressionLevel(flate.BestSpeed), "gzip-min")
    68  }
    69  
    70  func TestZlib(t *testing.T) {
    71  	testCompressionWith(t, NewZlibCompression(), "zlib")
    72  }