services/obs: Service test failed for content mismatch

[Xuanwo]

• Related PR: chore(services/*): Bump major versions #957
• Test Case: https://github.com/beyondstorage/go-storage/runs/3982686814?check_suite_focus=true

     When Read a file with offset or size 
      When Read with offset 
        The error should be nil ✔✔
        The content should be match ✔✘✔
      When Read with size 
        The error should be nil ✔✔
        The content should be match ✔✘✔
      When Read with offset and size 
        The error should be nil ✔✔
        The content should be match ✔✘✔

 Failures:

  * /data/actions/beta/go-storage/go-storage/services/obs/tests/storage_test.go 
  Line 14:
  Expected: '138112'
  Actual:   '451281'
  (Should be equal)

  * /data/actions/beta/go-storage/go-storage/services/obs/tests/storage_test.go 
  Line 14:
  Expected: '1288953'
  Actual:   '2688928'
  (Should be equal)

  * /data/actions/beta/go-storage/go-storage/services/obs/tests/storage_test.go 
  Line 14:
  Expected: '49793'
  Actual:   '291284'
  (Should be equal)

Obs implementation must be buggy, let's fix it before release.

[Xuanwo]

obs doesn't support offset and size now:

go-storage/services/obs/storage.go

Lines 185 to 202 in 9aa9a15

	func (s *Storage) read(ctx context.Context, path string, w io.Writer, opt pairStorageRead) (n int64, err error) {
	rp := s.getAbsPath(path)
	input := &obs.GetObjectInput{}
	input.Bucket = s.bucket
	input.Key = rp
	output, err := s.client.GetObject(input)
	if err != nil {
	return 0, err
	}
	rc := output.Body
	if opt.HasIoCallback {
	rc = iowrap.CallbackReadCloser(rc, opt.IoCallback)
	}
	return io.Copy(w, rc)

this can be fixed by like:

go-storage/services/bos/storage.go

Lines 181 to 193 in 9aa9a15

	func (s *Storage) read(ctx context.Context, path string, w io.Writer, opt pairStorageRead) (n int64, err error) {
	rp := s.getAbsPath(path)
	output := &api.GetObjectResult{}
	if opt.HasOffset && !opt.HasSize {
	output, err = s.client.GetObject(s.bucket, rp, nil, opt.Offset)
	} else if !opt.HasOffset && opt.HasSize {
	output, err = s.client.GetObject(s.bucket, rp, nil, 0, opt.Size-1)
	} else if opt.HasSize && opt.HasOffset {
	output, err = s.client.GetObject(s.bucket, rp, nil, opt.Offset, opt.Offset+opt.Size-1)
	} else {
	output, err = s.client.GetObject(s.bucket, rp, nil)
	}

[Xuanwo]

Wait for huaweicloud/huaweicloud-sdk-go-obs#10