|
17 | 17 |
|
18 | 18 | use std::ops::BitOrAssign; |
19 | 19 |
|
20 | | -use roaring::RoaringTreemap; |
| 20 | +use bytes::Buf; |
21 | 21 | use roaring::bitmap::Iter; |
22 | 22 | use roaring::treemap::BitmapIter; |
| 23 | +use roaring::{RoaringBitmap, RoaringTreemap}; |
23 | 24 |
|
24 | 25 | use crate::{Error, ErrorKind, Result}; |
25 | 26 |
|
| 27 | +/// Magic bytes prefixing a serialized `deletion-vector-v1` bitmap, per the Iceberg Puffin spec. |
| 28 | +/// Iceberg-Java stores these as the little-endian int 1681511377 (0x6439D3D1). |
| 29 | +const DV_MAGIC: [u8; 4] = [0xD1, 0xD3, 0x39, 0x64]; |
| 30 | +const DV_LENGTH_PREFIX_BYTES: usize = 4; |
| 31 | +const DV_MAGIC_BYTES: usize = 4; |
| 32 | +const DV_CRC_BYTES: usize = 4; |
| 33 | +const DV_MIN_BLOB_BYTES: usize = DV_LENGTH_PREFIX_BYTES + DV_MAGIC_BYTES + DV_CRC_BYTES; |
| 34 | + |
26 | 35 | #[derive(Debug, Default)] |
27 | 36 | pub struct DeleteVector { |
28 | 37 | inner: RoaringTreemap, |
@@ -68,6 +77,171 @@ impl DeleteVector { |
68 | 77 | pub fn len(&self) -> u64 { |
69 | 78 | self.inner.len() |
70 | 79 | } |
| 80 | + |
| 81 | + /// Parses a `deletion-vector-v1` Puffin blob into a `DeleteVector`. |
| 82 | + /// |
| 83 | + /// The layout, defined by the Iceberg Puffin spec and matching Iceberg-Java's |
| 84 | + /// `BitmapPositionDeleteIndex`, is: |
| 85 | + /// |
| 86 | + /// ```text |
| 87 | + /// [length: u32 big-endian][magic: D1 D3 39 64][vector][crc: u32 big-endian] |
| 88 | + /// ``` |
| 89 | + /// |
| 90 | + /// `length` counts the magic and vector bytes (not itself or the CRC). The CRC-32 is |
| 91 | + /// computed over the magic and vector. `vector` is a roaring bitmap in the portable 64-bit |
| 92 | + /// format: a directory of 32-bit key / 32-bit roaring bitmap pairs, ordered by unsigned |
| 93 | + /// comparison of the keys, one bitmap per key. |
| 94 | + /// |
| 95 | + /// Cardinality is not checked here. The caller validates the decoded length against the |
| 96 | + /// delete file's `record_count`, where the manifest metadata is available. |
| 97 | + /// |
| 98 | + /// # Errors |
| 99 | + /// |
| 100 | + /// Returns [`ErrorKind::DataInvalid`] if the blob is shorter than the minimum, the length |
| 101 | + /// prefix or CRC does not match, the magic is wrong, the roaring bitmap count exceeds the |
| 102 | + /// portable format's maximum, the roaring directory's keys are not ordered by unsigned |
| 103 | + /// comparison, or the roaring payload fails to decode. |
| 104 | + // Consumed by the scan delete loader once the deletion-vector read path is wired up. |
| 105 | + #[allow(dead_code)] |
| 106 | + pub fn deserialize(blob: &[u8]) -> Result<Self> { |
| 107 | + if blob.len() < DV_MIN_BLOB_BYTES { |
| 108 | + return Err(Error::new( |
| 109 | + ErrorKind::DataInvalid, |
| 110 | + format!( |
| 111 | + "deletion-vector-v1 blob is {} bytes, shorter than the {DV_MIN_BLOB_BYTES}-byte minimum", |
| 112 | + blob.len() |
| 113 | + ), |
| 114 | + )); |
| 115 | + } |
| 116 | + |
| 117 | + // The magic and vector, i.e. the bytes covered by both the length prefix and the CRC. |
| 118 | + let body = &blob[DV_LENGTH_PREFIX_BYTES..blob.len() - DV_CRC_BYTES]; |
| 119 | + verify_length_prefix(&blob[..DV_LENGTH_PREFIX_BYTES], body)?; |
| 120 | + |
| 121 | + // Verify the CRC before interpreting any bytes so a corrupt blob yields a single clear |
| 122 | + // error rather than an opaque roaring decode failure. |
| 123 | + verify_crc(body, &blob[blob.len() - DV_CRC_BYTES..])?; |
| 124 | + |
| 125 | + let (magic, vector) = body.split_at(DV_MAGIC_BYTES); |
| 126 | + verify_magic(magic)?; |
| 127 | + |
| 128 | + let inner = decode_roaring_directory(vector)?; |
| 129 | + |
| 130 | + Ok(DeleteVector { inner }) |
| 131 | + } |
| 132 | +} |
| 133 | + |
| 134 | +fn verify_length_prefix(mut prefix: &[u8], body: &[u8]) -> Result<()> { |
| 135 | + let declared_len = prefix.try_get_u32().map_err(|e| { |
| 136 | + Error::new( |
| 137 | + ErrorKind::Unexpected, |
| 138 | + "failed to read the deletion-vector-v1 length prefix", |
| 139 | + ) |
| 140 | + .with_source(e) |
| 141 | + })? as usize; |
| 142 | + if declared_len != body.len() { |
| 143 | + return Err(Error::new( |
| 144 | + ErrorKind::DataInvalid, |
| 145 | + format!( |
| 146 | + "deletion-vector-v1 length prefix is {declared_len}, expected {}", |
| 147 | + body.len() |
| 148 | + ), |
| 149 | + )); |
| 150 | + } |
| 151 | + Ok(()) |
| 152 | +} |
| 153 | + |
| 154 | +fn verify_crc(body: &[u8], mut crc_bytes: &[u8]) -> Result<()> { |
| 155 | + let stored_crc = crc_bytes.try_get_u32().map_err(|e| { |
| 156 | + Error::new( |
| 157 | + ErrorKind::Unexpected, |
| 158 | + "failed to read the deletion-vector-v1 CRC", |
| 159 | + ) |
| 160 | + .with_source(e) |
| 161 | + })?; |
| 162 | + let computed_crc = crc32fast::hash(body); |
| 163 | + if computed_crc != stored_crc { |
| 164 | + return Err(Error::new( |
| 165 | + ErrorKind::DataInvalid, |
| 166 | + format!( |
| 167 | + "deletion-vector-v1 CRC mismatch: computed {computed_crc:#010x}, stored {stored_crc:#010x}" |
| 168 | + ), |
| 169 | + )); |
| 170 | + } |
| 171 | + Ok(()) |
| 172 | +} |
| 173 | + |
| 174 | +fn verify_magic(magic: &[u8]) -> Result<()> { |
| 175 | + if magic != DV_MAGIC { |
| 176 | + return Err(Error::new( |
| 177 | + ErrorKind::DataInvalid, |
| 178 | + format!("deletion-vector-v1 magic mismatch: {magic:02x?}, expected {DV_MAGIC:02x?}"), |
| 179 | + )); |
| 180 | + } |
| 181 | + Ok(()) |
| 182 | +} |
| 183 | + |
| 184 | +// The Puffin spec defines the roaring directory as the bitmaps "ordered by unsigned comparison |
| 185 | +// of the 32-bit keys", with one bitmap per key. Walk it ourselves (rather than |
| 186 | +// `RoaringTreemap::deserialize_from`, which stores keys in a `BTreeMap` via a plain insert and |
| 187 | +// would silently accept a stream with duplicate or out-of-order keys, discarding the earlier |
| 188 | +// bitmap on a duplicate) so a non-conformant blob is rejected instead of decoded into a value |
| 189 | +// that doesn't match what was actually written. |
| 190 | +fn decode_roaring_directory(mut reader: &[u8]) -> Result<RoaringTreemap> { |
| 191 | + let bitmap_count = reader.try_get_u64_le().map_err(|e| { |
| 192 | + Error::new( |
| 193 | + ErrorKind::DataInvalid, |
| 194 | + "failed to decode deletion-vector-v1 roaring payload", |
| 195 | + ) |
| 196 | + .with_source(e) |
| 197 | + })?; |
| 198 | + // The roaring portable format restricts the bitmap count to [0, 2^32 - 1] (it is stored as a |
| 199 | + // u64 with the upper 32 bits reserved as zero padding). |
| 200 | + if bitmap_count > u32::MAX as u64 { |
| 201 | + return Err(Error::new( |
| 202 | + ErrorKind::DataInvalid, |
| 203 | + format!( |
| 204 | + "deletion-vector-v1 roaring bitmap count {bitmap_count} exceeds the {}-key maximum", |
| 205 | + u32::MAX |
| 206 | + ), |
| 207 | + )); |
| 208 | + } |
| 209 | + |
| 210 | + let mut bitmaps = Vec::new(); |
| 211 | + let mut last_key: Option<u32> = None; |
| 212 | + for _ in 0..bitmap_count { |
| 213 | + let key = reader.try_get_u32_le().map_err(|e| { |
| 214 | + Error::new( |
| 215 | + ErrorKind::DataInvalid, |
| 216 | + "failed to decode deletion-vector-v1 roaring payload", |
| 217 | + ) |
| 218 | + .with_source(e) |
| 219 | + })?; |
| 220 | + if let Some(last) = last_key |
| 221 | + && key <= last |
| 222 | + { |
| 223 | + return Err(Error::new( |
| 224 | + ErrorKind::DataInvalid, |
| 225 | + format!( |
| 226 | + "deletion-vector-v1 roaring keys must be ordered by unsigned comparison, got key {key} after {last}" |
| 227 | + ), |
| 228 | + )); |
| 229 | + } |
| 230 | + last_key = Some(key); |
| 231 | + |
| 232 | + let bitmap = RoaringBitmap::deserialize_from(&mut reader).map_err(|e| { |
| 233 | + Error::new( |
| 234 | + ErrorKind::DataInvalid, |
| 235 | + "failed to decode deletion-vector-v1 roaring payload", |
| 236 | + ) |
| 237 | + .with_source(e) |
| 238 | + })?; |
| 239 | + bitmaps.push((key, bitmap)); |
| 240 | + } |
| 241 | + |
| 242 | + // `bitmaps` is already sorted by key, but `roaring` has no constructor that accepts |
| 243 | + // pre-sorted pairs without re-sorting them; revisit if that changes upstream. |
| 244 | + Ok(RoaringTreemap::from_bitmaps(bitmaps)) |
71 | 245 | } |
72 | 246 |
|
73 | 247 | // Ideally, we'd just wrap `roaring::RoaringTreemap`'s iterator, `roaring::treemap::Iter` here. |
@@ -198,4 +372,158 @@ mod tests { |
198 | 372 | let res = dv.insert_positions(&positions); |
199 | 373 | assert!(res.is_err()); |
200 | 374 | } |
| 375 | + |
| 376 | + // Reproduces Iceberg-Java's `deletion-vector-v1` framing so tests can round-trip through |
| 377 | + // `deserialize` without a Java writer. Cross-implementation golden fixtures produced by |
| 378 | + // Iceberg-Java are tracked separately; this only checks that our decode matches our encode. |
| 379 | + fn frame_dv_blob(vector: &[u8]) -> Vec<u8> { |
| 380 | + let body_len = DV_MAGIC_BYTES + vector.len(); |
| 381 | + let mut blob = Vec::with_capacity(DV_LENGTH_PREFIX_BYTES + body_len + DV_CRC_BYTES); |
| 382 | + blob.extend_from_slice(&(body_len as u32).to_be_bytes()); |
| 383 | + blob.extend_from_slice(&DV_MAGIC); |
| 384 | + blob.extend_from_slice(vector); |
| 385 | + let crc = crc32fast::hash(&blob[DV_LENGTH_PREFIX_BYTES..]); |
| 386 | + blob.extend_from_slice(&crc.to_be_bytes()); |
| 387 | + blob |
| 388 | + } |
| 389 | + |
| 390 | + fn encode_dv_blob(dv: &DeleteVector) -> Vec<u8> { |
| 391 | + let mut vector = Vec::with_capacity(dv.inner.serialized_size()); |
| 392 | + dv.inner.serialize_into(&mut vector).unwrap(); |
| 393 | + frame_dv_blob(&vector) |
| 394 | + } |
| 395 | + |
| 396 | + fn dv_of(positions: impl IntoIterator<Item = u64>) -> DeleteVector { |
| 397 | + let mut dv = DeleteVector::default(); |
| 398 | + for pos in positions { |
| 399 | + dv.insert(pos); |
| 400 | + } |
| 401 | + dv |
| 402 | + } |
| 403 | + |
| 404 | + fn sorted(dv: &DeleteVector) -> Vec<u64> { |
| 405 | + let mut positions: Vec<u64> = dv.iter().collect(); |
| 406 | + positions.sort_unstable(); |
| 407 | + positions |
| 408 | + } |
| 409 | + |
| 410 | + #[test] |
| 411 | + fn test_deserialize_roundtrip_empty() { |
| 412 | + let blob = encode_dv_blob(&DeleteVector::default()); |
| 413 | + assert_eq!(DeleteVector::deserialize(&blob).unwrap().len(), 0); |
| 414 | + } |
| 415 | + |
| 416 | + #[test] |
| 417 | + fn test_deserialize_roundtrip_small() { |
| 418 | + let positions = [0u64, 5, 100, 1000]; |
| 419 | + let dv = DeleteVector::deserialize(&encode_dv_blob(&dv_of(positions))).unwrap(); |
| 420 | + assert_eq!(sorted(&dv), positions); |
| 421 | + } |
| 422 | + |
| 423 | + #[test] |
| 424 | + fn test_deserialize_roundtrip_spanning_64bit_keys() { |
| 425 | + let positions = [1u64, 1 << 33, (1 << 33) + 5, 1 << 34]; |
| 426 | + let dv = DeleteVector::deserialize(&encode_dv_blob(&dv_of(positions))).unwrap(); |
| 427 | + assert_eq!(sorted(&dv), positions); |
| 428 | + } |
| 429 | + |
| 430 | + // Java run-optimizes every deletion vector before writing, so real blobs carry RUN |
| 431 | + // containers, which use the SERIAL_COOKIE roaring layout. Force that layout so decode |
| 432 | + // exercises the run-container path rather than only array and bitmap containers. |
| 433 | + #[test] |
| 434 | + fn test_deserialize_roundtrip_run_optimized() { |
| 435 | + let mut dv = dv_of(0..10_000); |
| 436 | + assert!( |
| 437 | + dv.inner.optimize(), |
| 438 | + "expected a dense range to run-length encode" |
| 439 | + ); |
| 440 | + let decoded = DeleteVector::deserialize(&encode_dv_blob(&dv)).unwrap(); |
| 441 | + assert_eq!(decoded.len(), 10_000); |
| 442 | + let positions = sorted(&decoded); |
| 443 | + assert_eq!(positions.first(), Some(&0)); |
| 444 | + assert_eq!(positions.last(), Some(&9_999)); |
| 445 | + } |
| 446 | + |
| 447 | + #[test] |
| 448 | + fn test_deserialize_rejects_short_blob() { |
| 449 | + let err = DeleteVector::deserialize(&[0u8; DV_MIN_BLOB_BYTES - 1]).unwrap_err(); |
| 450 | + assert_eq!(err.kind(), ErrorKind::DataInvalid); |
| 451 | + } |
| 452 | + |
| 453 | + #[test] |
| 454 | + fn test_deserialize_rejects_bad_magic() { |
| 455 | + let mut blob = encode_dv_blob(&dv_of([1])); |
| 456 | + blob[DV_LENGTH_PREFIX_BYTES] ^= 0xFF; |
| 457 | + // Recompute the CRC so the magic check, not the CRC check, is what fails. |
| 458 | + let end = blob.len() - DV_CRC_BYTES; |
| 459 | + let crc = crc32fast::hash(&blob[DV_LENGTH_PREFIX_BYTES..end]); |
| 460 | + blob[end..].copy_from_slice(&crc.to_be_bytes()); |
| 461 | + let err = DeleteVector::deserialize(&blob).unwrap_err(); |
| 462 | + assert!(err.message().contains("magic mismatch"), "got: {err}"); |
| 463 | + } |
| 464 | + |
| 465 | + #[test] |
| 466 | + fn test_deserialize_rejects_bad_crc() { |
| 467 | + let mut blob = encode_dv_blob(&dv_of([1, 2, 3])); |
| 468 | + let end = blob.len() - DV_CRC_BYTES; |
| 469 | + blob[end] ^= 0xFF; |
| 470 | + let err = DeleteVector::deserialize(&blob).unwrap_err(); |
| 471 | + assert!(err.message().contains("CRC mismatch"), "got: {err}"); |
| 472 | + } |
| 473 | + |
| 474 | + #[test] |
| 475 | + fn test_deserialize_rejects_length_prefix_mismatch() { |
| 476 | + let mut blob = encode_dv_blob(&dv_of([1])); |
| 477 | + let declared = u32::from_be_bytes(blob[..DV_LENGTH_PREFIX_BYTES].try_into().unwrap()); |
| 478 | + blob[..DV_LENGTH_PREFIX_BYTES].copy_from_slice(&(declared + 1).to_be_bytes()); |
| 479 | + let err = DeleteVector::deserialize(&blob).unwrap_err(); |
| 480 | + assert!(err.message().contains("length prefix"), "got: {err}"); |
| 481 | + } |
| 482 | + |
| 483 | + // Crafts a raw roaring treemap directory (bitmap count header + key/bitmap entries) so tests |
| 484 | + // can exercise key-ordering violations that `dv_of`/`encode_dv_blob` can never produce, since |
| 485 | + // `DeleteVector::insert` always keeps keys unique and ascending. |
| 486 | + fn raw_roaring_vector(entries: &[(u32, &[u32])]) -> Vec<u8> { |
| 487 | + let mut vector = Vec::new(); |
| 488 | + vector.extend_from_slice(&(entries.len() as u64).to_le_bytes()); |
| 489 | + for (key, positions) in entries { |
| 490 | + let mut bitmap = RoaringBitmap::new(); |
| 491 | + for &pos in *positions { |
| 492 | + bitmap.insert(pos); |
| 493 | + } |
| 494 | + vector.extend_from_slice(&key.to_le_bytes()); |
| 495 | + bitmap.serialize_into(&mut vector).unwrap(); |
| 496 | + } |
| 497 | + vector |
| 498 | + } |
| 499 | + |
| 500 | + // `RoaringTreemap::deserialize_from` stores keys in a `BTreeMap` via a plain insert, so |
| 501 | + // without our own ordering check, decoding this would silently keep only the second bitmap |
| 502 | + // for key 5 (position 2) and drop the first (position 1). |
| 503 | + #[test] |
| 504 | + fn test_deserialize_rejects_duplicate_keys() { |
| 505 | + let vector = raw_roaring_vector(&[(5, &[1]), (5, &[2])]); |
| 506 | + let err = DeleteVector::deserialize(&frame_dv_blob(&vector)).unwrap_err(); |
| 507 | + assert!(err.message().contains("unsigned comparison"), "got: {err}"); |
| 508 | + } |
| 509 | + |
| 510 | + // The Puffin spec requires the roaring directory's keys to be "ordered by unsigned |
| 511 | + // comparison"; a stream with unique but out-of-order keys is not a conformant blob even |
| 512 | + // though `BTreeMap` would happily reorder it into a correct-looking result. |
| 513 | + #[test] |
| 514 | + fn test_deserialize_rejects_out_of_order_keys() { |
| 515 | + let vector = raw_roaring_vector(&[(5, &[1]), (3, &[2])]); |
| 516 | + let err = DeleteVector::deserialize(&frame_dv_blob(&vector)).unwrap_err(); |
| 517 | + assert!(err.message().contains("unsigned comparison"), "got: {err}"); |
| 518 | + } |
| 519 | + |
| 520 | + // The roaring portable format stores the bitmap count as a u64 with the upper 32 bits |
| 521 | + // reserved as zero padding, restricting it to [0, 2^32 - 1]; a value above that is not a |
| 522 | + // conformant blob, regardless of whether any key/bitmap entries follow. |
| 523 | + #[test] |
| 524 | + fn test_deserialize_rejects_bitmap_count_overflow() { |
| 525 | + let vector = (u32::MAX as u64 + 1).to_le_bytes().to_vec(); |
| 526 | + let err = DeleteVector::deserialize(&frame_dv_blob(&vector)).unwrap_err(); |
| 527 | + assert!(err.message().contains("exceeds the"), "got: {err}"); |
| 528 | + } |
201 | 529 | } |
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