Shreyas220 commented on code in PR #676: URL: https://github.com/apache/iceberg-go/pull/676#discussion_r2689765584
########## puffin/puffin_writer.go: ########## @@ -0,0 +1,213 @@ +// Licensed to the Apache Software Foundation (ASF) under one +// or more contributor license agreements. See the NOTICE file +// distributed with this work for additional information +// regarding copyright ownership. The ASF licenses this file +// to you 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 puffin + +import ( + "encoding/binary" + "encoding/json" + "errors" + "fmt" + "io" + "math" +) + +// writeAll writes all bytes to w or returns an error. +// Handles the io.Writer contract where Write can return n < len(data) without error. +func writeAll(w io.Writer, data []byte) error { + n, err := w.Write(data) + if err != nil { + return err + } + if n != len(data) { + return fmt.Errorf("short write: wrote %d of %d bytes", n, len(data)) + } + + return nil +} + +// PuffinWriter writes blobs and metadata to a Puffin file. +// +// The Puffin format stores arbitrary blobs (e.g., statistics, deletion vectors) +// along with JSON metadata in a footer. The writer handles the binary layout: +// header magic, blob data, and footer structure. +// +// Usage: +// +// w, err := puffin.NewWriter(file) +// if err != nil { +// return err +// } +// _, err = w.AddBlob(puffin.BlobMetadataInput{ +// Type: puffin.ApacheDataSketchesThetaV1, +// SnapshotID: 123, +// Fields: []int32{1}, +// }, sketchBytes) +// if err != nil { +// return err +// } +// return w.Finish() +type PuffinWriter struct { + w io.Writer + offset int64 + blobs []BlobMetadata + props map[string]string + done bool + createdBy string +} + +// BlobMetadataInput contains fields the caller provides when adding a blob. +// Offset, Length, and CompressionCodec are set by the writer. +type BlobMetadataInput struct { + Type string + SnapshotID int64 + SequenceNumber int64 + Fields []int32 + Properties map[string]string +} + +// NewWriter creates a new PuffinWriter and writes the file header magic. +// The caller is responsible for closing the underlying writer after Finish returns. +func NewWriter(w io.Writer) (*PuffinWriter, error) { + if w == nil { + return nil, errors.New("puffin: writer is nil") + } + + // Write header magic bytes + if err := writeAll(w, magic[:]); err != nil { + return nil, fmt.Errorf("puffin: write header magic: %w", err) + } + + return &PuffinWriter{ + w: w, + offset: MagicSize, + props: make(map[string]string), + createdBy: "iceberg-go", + }, nil +} + +// SetProperties merges the provided properties into the file-level properties +// written to the footer. Can be called multiple times before Finish. +func (w *PuffinWriter) SetProperties(props map[string]string) error { Review Comment: Added ClearProperties() method . is there a requirement for removing a specific property ? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
