prometheus/storage/remote/chunked_test.go

107 lines
2.7 KiB
Go

// Copyright 2019 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package remote
import (
"bytes"
"io"
"testing"
"github.com/stretchr/testify/require"
)
type mockedFlusher struct {
flushed int
}
func (f *mockedFlusher) Flush() {
f.flushed++
}
func TestChunkedReaderCanReadFromChunkedWriter(t *testing.T) {
b := &bytes.Buffer{}
f := &mockedFlusher{}
w := NewChunkedWriter(b, f)
r := NewChunkedReader(b, 20, nil)
msgs := [][]byte{
[]byte("test1"),
[]byte("test2"),
[]byte("test3"),
[]byte("test4"),
{}, // This is ignored by writer.
[]byte("test5-after-empty"),
}
for _, msg := range msgs {
n, err := w.Write(msg)
require.NoError(t, err)
require.Len(t, msg, n)
}
i := 0
for ; i < 4; i++ {
msg, err := r.Next()
require.NoError(t, err)
require.Less(t, i, len(msgs), "more messages then expected")
require.Equal(t, msgs[i], msg)
}
// Empty byte slice is skipped.
i++
msg, err := r.Next()
require.NoError(t, err)
require.Less(t, i, len(msgs), "more messages then expected")
require.Equal(t, msgs[i], msg)
_, err = r.Next()
require.Error(t, err, "expected io.EOF")
require.Equal(t, io.EOF, err)
require.Equal(t, 5, f.flushed)
}
func TestChunkedReader_Overflow(t *testing.T) {
b := &bytes.Buffer{}
_, err := NewChunkedWriter(b, &mockedFlusher{}).Write([]byte("twelve bytes"))
require.NoError(t, err)
b2 := make([]byte, 12)
copy(b2, b.Bytes())
ret, err := NewChunkedReader(b, 12, nil).Next()
require.NoError(t, err)
require.Equal(t, "twelve bytes", string(ret))
_, err = NewChunkedReader(bytes.NewReader(b2), 11, nil).Next()
require.Error(t, err, "expect exceed limit error")
require.EqualError(t, err, "chunkedReader: message size exceeded the limit 11 bytes; got: 12 bytes")
}
func TestChunkedReader_CorruptedFrame(t *testing.T) {
b := &bytes.Buffer{}
w := NewChunkedWriter(b, &mockedFlusher{})
n, err := w.Write([]byte("test1"))
require.NoError(t, err)
require.Equal(t, 5, n)
bs := b.Bytes()
bs[9] = 1 // Malform the frame by changing one byte.
_, err = NewChunkedReader(bytes.NewReader(bs), 20, nil).Next()
require.Error(t, err, "expected malformed frame")
require.EqualError(t, err, "chunkedReader: corrupted frame; checksum mismatch")
}