Extract ModuloReader from service.go
continuous-integration/drone/push Build is passing Details

This commit is contained in:
Rob Watson 2021-12-17 17:52:59 +01:00
parent 2445ebc02f
commit dd526b6916
4 changed files with 125 additions and 110 deletions

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@ -0,0 +1,43 @@
package media
import (
"bytes"
"io"
)
// ModuloReader reads from a reader in block sizes that are exactly modulo
// modSize, with any remainder buffered until the next read.
type ModuloReader struct {
io.ReadCloser
buf bytes.Buffer
modSize int
}
func NewModuloReader(r io.ReadCloser, modSize int) *ModuloReader {
return &ModuloReader{ReadCloser: r, modSize: modSize}
}
func (r *ModuloReader) Read(p []byte) (int, error) {
// err is always io.EOF or nil
nr1, _ := r.buf.Read(p)
nr2, err := r.ReadCloser.Read(p[nr1:])
nr := nr1 + nr2
rem := nr % r.modSize
// if there was an error, return immediately.
if err == io.EOF {
return nr, err
} else if err != nil {
return nr - rem, err
}
// write any remainder to the buffer
if rem != 0 {
// err is always nil
_, _ = r.buf.Write(p[nr-rem : nr])
}
return nr - rem, err
}

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@ -0,0 +1,80 @@
package media_test
import (
"io"
"testing"
"git.netflux.io/rob/clipper/media"
"github.com/stretchr/testify/assert"
)
type testReader struct {
count int
data [][]byte
}
func (r *testReader) Read(p []byte) (int, error) {
if r.count == len(r.data) {
return 0, io.EOF
}
n := copy(p, r.data[r.count])
r.count++
return n, nil
}
func TestModuloBufReader(t *testing.T) {
reader := testReader{
data: [][]byte{
{'a', 'b', 'c', 'd'},
{'e', 'f', 'g', 'h', 'i'},
{},
{'j', 'k', 'l', 'm'},
{'n', 'o', 'p'},
{'q', 'r', 's', 't', 'u'},
},
}
modReader := media.NewModuloReader(io.NopCloser(&reader), 4)
out := make([]byte, 5)
n, err := modReader.Read(out)
assert.NoError(t, err)
assert.Equal(t, 4, n)
assert.Equal(t, []byte{'a', 'b', 'c', 'd'}, out[:n])
n, err = modReader.Read(out)
assert.NoError(t, err)
assert.Equal(t, 4, n)
assert.Equal(t, []byte{'e', 'f', 'g', 'h'}, out[:n])
n, err = modReader.Read(out)
assert.NoError(t, err)
assert.Zero(t, n)
assert.Empty(t, out[:n])
n, err = modReader.Read(out)
assert.NoError(t, err)
assert.NoError(t, err)
assert.Equal(t, 4, n)
assert.Equal(t, []byte{'i', 'j', 'k', 'l'}, out[:n])
n, err = modReader.Read(out)
assert.NoError(t, err)
assert.Equal(t, 4, n)
assert.Equal(t, []byte{'m', 'n', 'o', 'p'}, out[:n])
n, err = modReader.Read(out)
assert.NoError(t, err)
assert.Equal(t, 4, n)
assert.Equal(t, []byte{'q', 'r', 's', 't'}, out[:n])
n, err = modReader.Read(out)
assert.Equal(t, io.EOF, err)
assert.Equal(t, 1, n)
assert.Equal(t, []byte{'u'}, out[:n])
n, err = modReader.Read(out)
assert.Zero(t, n)
assert.Equal(t, io.EOF, err)
}

View File

@ -291,7 +291,7 @@ func (s *MediaSetService) getPeaksFromFileStore(ctx context.Context, mediaSet st
state := getPeaksFromFileStoreState{ state := getPeaksFromFileStoreState{
getPeaksProgressReader: getPeaksProgressReader, getPeaksProgressReader: getPeaksProgressReader,
reader: NewModuloBufReader(object, int(mediaSet.AudioChannels)*SizeOfInt16), reader: NewModuloReader(object, int(mediaSet.AudioChannels)*SizeOfInt16),
fileStore: s.fileStore, fileStore: s.fileStore,
config: s.config, config: s.config,
logger: s.logger, logger: s.logger,
@ -376,7 +376,7 @@ func (s *MediaSetService) GetPeaksForSegment(ctx context.Context, id uuid.UUID,
const readBufSizeBytes = 8_192 const readBufSizeBytes = 8_192
channels := int(mediaSet.AudioChannels) channels := int(mediaSet.AudioChannels)
modReader := NewModuloBufReader(object, channels*SizeOfInt16) modReader := NewModuloReader(object, channels*SizeOfInt16)
readBuf := make([]byte, readBufSizeBytes) readBuf := make([]byte, readBufSizeBytes)
peaks := make([]int16, channels*numBins) peaks := make([]int16, channels*numBins)
totalFrames := endFrame - startFrame totalFrames := endFrame - startFrame
@ -449,43 +449,6 @@ func sqlInt32(i int32) sql.NullInt32 {
return sql.NullInt32{Int32: i, Valid: true} return sql.NullInt32{Int32: i, Valid: true}
} }
// ModuloBufReader reads from a reader in block sizes that are exactly modulo
// modSize, with any remainder buffered until the next read.
type ModuloBufReader struct {
io.ReadCloser
buf bytes.Buffer
modSize int
}
func NewModuloBufReader(r io.ReadCloser, modSize int) *ModuloBufReader {
return &ModuloBufReader{ReadCloser: r, modSize: modSize}
}
func (r *ModuloBufReader) Read(p []byte) (int, error) {
// err is always io.EOF or nil
nr1, _ := r.buf.Read(p)
nr2, err := r.ReadCloser.Read(p[nr1:])
nr := nr1 + nr2
rem := nr % r.modSize
// if there was an error, return immediately.
if err == io.EOF {
return nr, err
} else if err != nil {
return nr - rem, err
}
// write any remainder to the buffer
if rem != 0 {
// err is always nil
_, _ = r.buf.Write(p[nr-rem : nr])
}
return nr - rem, err
}
type VideoThumbnail struct { type VideoThumbnail struct {
Data []byte Data []byte
Width, Height int Width, Height int

View File

@ -160,74 +160,3 @@ func BenchmarkGetPeaksForSegment(b *testing.B) {
require.NoError(b, err) require.NoError(b, err)
} }
} }
type testReader struct {
count int
data [][]byte
}
func (r *testReader) Read(p []byte) (int, error) {
if r.count == len(r.data) {
return 0, io.EOF
}
n := copy(p, r.data[r.count])
r.count++
return n, nil
}
func TestModuloBufReader(t *testing.T) {
reader := testReader{
data: [][]byte{
{'a', 'b', 'c', 'd'},
{'e', 'f', 'g', 'h', 'i'},
{},
{'j', 'k', 'l', 'm'},
{'n', 'o', 'p'},
{'q', 'r', 's', 't', 'u'},
},
}
modReader := media.NewModuloBufReader(io.NopCloser(&reader), 4)
out := make([]byte, 5)
n, err := modReader.Read(out)
assert.NoError(t, err)
assert.Equal(t, 4, n)
assert.Equal(t, []byte{'a', 'b', 'c', 'd'}, out[:n])
n, err = modReader.Read(out)
assert.NoError(t, err)
assert.Equal(t, 4, n)
assert.Equal(t, []byte{'e', 'f', 'g', 'h'}, out[:n])
n, err = modReader.Read(out)
assert.NoError(t, err)
assert.Zero(t, n)
assert.Empty(t, out[:n])
n, err = modReader.Read(out)
assert.NoError(t, err)
assert.NoError(t, err)
assert.Equal(t, 4, n)
assert.Equal(t, []byte{'i', 'j', 'k', 'l'}, out[:n])
n, err = modReader.Read(out)
assert.NoError(t, err)
assert.Equal(t, 4, n)
assert.Equal(t, []byte{'m', 'n', 'o', 'p'}, out[:n])
n, err = modReader.Read(out)
assert.NoError(t, err)
assert.Equal(t, 4, n)
assert.Equal(t, []byte{'q', 'r', 's', 't'}, out[:n])
n, err = modReader.Read(out)
assert.Equal(t, io.EOF, err)
assert.Equal(t, 1, n)
assert.Equal(t, []byte{'u'}, out[:n])
n, err = modReader.Read(out)
assert.Zero(t, n)
assert.Equal(t, io.EOF, err)
}