1 files changed, 133 insertions, 0 deletions
diff --git a/services/packages/container/blob_uploader.go b/services/packages/container/blob_uploader.go
new file mode 100644
index 0000000..bae2e2d
--- /dev/null
+++ b/services/packages/container/blob_uploader.go
@@ -0,0 +1,133 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package container
+
+import (
+	"context"
+	"errors"
+	"io"
+	"os"
+
+	packages_model "code.gitea.io/gitea/models/packages"
+	packages_module "code.gitea.io/gitea/modules/packages"
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/util"
+)
+
+var (
+	// errWriteAfterRead occurs if Write is called after a read operation
+	errWriteAfterRead = errors.New("write is unsupported after a read operation")
+	// errOffsetMissmatch occurs if the file offset is different than the model
+	errOffsetMissmatch = errors.New("offset mismatch between file and model")
+)
+
+// BlobUploader handles chunked blob uploads
+type BlobUploader struct {
+	*packages_model.PackageBlobUpload
+	*packages_module.MultiHasher
+	file    *os.File
+	reading bool
+}
+
+func buildFilePath(id string) string {
+	return util.FilePathJoinAbs(setting.Packages.ChunkedUploadPath, id)
+}
+
+// NewBlobUploader creates a new blob uploader for the given id
+func NewBlobUploader(ctx context.Context, id string) (*BlobUploader, error) {
+	model, err := packages_model.GetBlobUploadByID(ctx, id)
+	if err != nil {
+		return nil, err
+	}
+
+	hash := packages_module.NewMultiHasher()
+	if len(model.HashStateBytes) != 0 {
+		if err := hash.UnmarshalBinary(model.HashStateBytes); err != nil {
+			return nil, err
+		}
+	}
+
+	f, err := os.OpenFile(buildFilePath(model.ID), os.O_RDWR|os.O_CREATE, 0o666)
+	if err != nil {
+		return nil, err
+	}
+
+	return &BlobUploader{
+		model,
+		hash,
+		f,
+		false,
+	}, nil
+}
+
+// Close implements io.Closer
+func (u *BlobUploader) Close() error {
+	return u.file.Close()
+}
+
+// Append appends a chunk of data and updates the model
+func (u *BlobUploader) Append(ctx context.Context, r io.Reader) error {
+	if u.reading {
+		return errWriteAfterRead
+	}
+
+	offset, err := u.file.Seek(0, io.SeekEnd)
+	if err != nil {
+		return err
+	}
+	if offset != u.BytesReceived {
+		return errOffsetMissmatch
+	}
+
+	n, err := io.Copy(io.MultiWriter(u.file, u.MultiHasher), r)
+	if err != nil {
+		return err
+	}
+
+	// fast path if nothing was written
+	if n == 0 {
+		return nil
+	}
+
+	u.BytesReceived += n
+
+	u.HashStateBytes, err = u.MultiHasher.MarshalBinary()
+	if err != nil {
+		return err
+	}
+
+	return packages_model.UpdateBlobUpload(ctx, u.PackageBlobUpload)
+}
+
+func (u *BlobUploader) Size() int64 {
+	return u.BytesReceived
+}
+
+// Read implements io.Reader
+func (u *BlobUploader) Read(p []byte) (int, error) {
+	if !u.reading {
+		_, err := u.file.Seek(0, io.SeekStart)
+		if err != nil {
+			return 0, err
+		}
+
+		u.reading = true
+	}
+
+	return u.file.Read(p)
+}
+
+// Remove deletes the data and the model of a blob upload
+func RemoveBlobUploadByID(ctx context.Context, id string) error {
+	if err := packages_model.DeleteBlobUploadByID(ctx, id); err != nil {
+		return err
+	}
+
+	err := os.Remove(buildFilePath(id))
+	if err != nil && !os.IsNotExist(err) {
+		return err
+	}
+
+	return nil
+}