buoyant_kernel 0.22.0

Buoyant Data distribution of delta-kernel
Documentation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
//! For now we just use simple functions to deserialize table properties from strings. This allows
//! us to relatively simply implement the functionality described in the protocol and expose
//! 'simple' types to the user in the [`TableProperties`] struct. E.g. we can expose a `bool`
//! directly instead of a `BoolConfig` type that we implement `Deserialize` for.
use std::num::NonZero;
use std::time::Duration;

use tracing::warn;

use super::*;
use crate::expressions::ColumnName;
use crate::table_features::ColumnMappingMode;
use crate::utils::require;

const SECONDS_PER_MINUTE: u64 = 60;
const SECONDS_PER_HOUR: u64 = 60 * SECONDS_PER_MINUTE;
const SECONDS_PER_DAY: u64 = 24 * SECONDS_PER_HOUR;
const SECONDS_PER_WEEK: u64 = 7 * SECONDS_PER_DAY;

impl<K, V, I> From<I> for TableProperties
where
    I: IntoIterator<Item = (K, V)>,
    K: AsRef<str> + Into<String>,
    V: AsRef<str> + Into<String>,
{
    fn from(unparsed: I) -> Self {
        let mut props = TableProperties::default();
        let unparsed = unparsed.into_iter().filter(|(k, v)| {
            // Only keep elements that fail to parse
            try_parse(&mut props, k.as_ref(), v.as_ref()).is_none()
        });
        props.unknown_properties = unparsed.map(|(k, v)| (k.into(), v.into())).collect();
        props
    }
}

// attempt to parse a key-value pair into a `TableProperties` struct. Returns Some(()) if the key
// was successfully parsed, and None otherwise.
fn try_parse(props: &mut TableProperties, k: &str, v: &str) -> Option<()> {
    // Table property key constants are imported via `use super::*` at the top of this file.

    // NOTE!! we do Some(parse(v)?) instead of just parse(v) because we want to return None if the
    // parsing fails. If we simply call 'parse(v)', then we would (incorrectly) return Some(()) and
    // just set the property to None.
    match k {
        APPEND_ONLY => props.append_only = Some(parse_bool(v)?),
        AUTO_COMPACT => props.auto_compact = Some(parse_bool(v)?),
        OPTIMIZE_WRITE => props.optimize_write = Some(parse_bool(v)?),
        CHECKPOINT_INTERVAL => props.checkpoint_interval = Some(parse_positive_int(v)?),
        CHECKPOINT_WRITE_STATS_AS_JSON => {
            props.checkpoint_write_stats_as_json = Some(parse_bool(v)?)
        }
        CHECKPOINT_WRITE_STATS_AS_STRUCT => {
            props.checkpoint_write_stats_as_struct = Some(parse_bool(v)?)
        }
        COLUMN_MAPPING_MODE => props.column_mapping_mode = ColumnMappingMode::try_from(v).ok(),
        COLUMN_MAPPING_MAX_COLUMN_ID => {
            props.column_mapping_max_column_id = Some(parse_non_negative(v)?)
        }
        DATA_SKIPPING_NUM_INDEXED_COLS => {
            props.data_skipping_num_indexed_cols = DataSkippingNumIndexedCols::try_from(v).ok()
        }
        DATA_SKIPPING_STATS_COLUMNS => {
            props.data_skipping_stats_columns = Some(parse_column_names(v)?)
        }
        DELETED_FILE_RETENTION_DURATION => {
            props.deleted_file_retention_duration = Some(parse_interval(v)?)
        }
        ENABLE_CHANGE_DATA_FEED => props.enable_change_data_feed = Some(parse_bool(v)?),
        ENABLE_DELETION_VECTORS => props.enable_deletion_vectors = Some(parse_bool(v)?),
        ENABLE_TYPE_WIDENING => props.enable_type_widening = Some(parse_bool(v)?),
        ENABLE_ICEBERG_COMPAT_V1 => props.enable_iceberg_compat_v1 = Some(parse_bool(v)?),
        ENABLE_ICEBERG_COMPAT_V2 => props.enable_iceberg_compat_v2 = Some(parse_bool(v)?),
        ENABLE_ICEBERG_COMPAT_V3 => props.enable_iceberg_compat_v3 = Some(parse_bool(v)?),
        ISOLATION_LEVEL => props.isolation_level = IsolationLevel::try_from(v).ok(),
        LOG_RETENTION_DURATION => props.log_retention_duration = Some(parse_interval(v)?),
        ENABLE_EXPIRED_LOG_CLEANUP => props.enable_expired_log_cleanup = Some(parse_bool(v)?),
        RANDOMIZE_FILE_PREFIXES => props.randomize_file_prefixes = Some(parse_bool(v)?),
        RANDOM_PREFIX_LENGTH => props.random_prefix_length = Some(parse_positive_int(v)?),
        SET_TRANSACTION_RETENTION_DURATION => {
            props.set_transaction_retention_duration = Some(parse_interval(v)?)
        }
        TARGET_FILE_SIZE => props.target_file_size = Some(parse_positive_int(v)?),
        TUNE_FILE_SIZES_FOR_REWRITES => props.tune_file_sizes_for_rewrites = Some(parse_bool(v)?),
        CHECKPOINT_POLICY => props.checkpoint_policy = CheckpointPolicy::try_from(v).ok(),
        ENABLE_ROW_TRACKING => props.enable_row_tracking = Some(parse_bool(v)?),
        MATERIALIZED_ROW_ID_COLUMN_NAME => {
            props.materialized_row_id_column_name = Some(v.to_string())
        }
        MATERIALIZED_ROW_COMMIT_VERSION_COLUMN_NAME => {
            props.materialized_row_commit_version_column_name = Some(v.to_string())
        }
        ROW_TRACKING_SUSPENDED => props.row_tracking_suspended = Some(parse_bool(v)?),
        PARQUET_FORMAT_VERSION => props.parquet_format_version = Some(v.to_string()),
        PARQUET_COMPRESSION_CODEC => {
            // Preserve unrecognized codecs in `unknown_properties` so connectors can fall back
            // themselves.
            props.parquet_compression_codec = Some(ParquetCompressionCodec::try_from(v).ok()?)
        }
        ENABLE_IN_COMMIT_TIMESTAMPS => props.enable_in_commit_timestamps = Some(parse_bool(v)?),
        IN_COMMIT_TIMESTAMP_ENABLEMENT_VERSION => {
            props.in_commit_timestamp_enablement_version = Some(parse_non_negative(v)?)
        }
        IN_COMMIT_TIMESTAMP_ENABLEMENT_TIMESTAMP => {
            props.in_commit_timestamp_enablement_timestamp = Some(parse_non_negative(v)?)
        }
        _ => return None,
    }
    Some(())
}

/// Deserialize a string representing a positive (> 0) integer into an `Option<u64>`. Returns `Some`
/// if successfully parses, and `None` otherwise.
pub(crate) fn parse_positive_int(s: &str) -> Option<NonZero<u64>> {
    // parse as non-negative and verify the result is non-zero
    NonZero::new(parse_non_negative(s)?)
}

/// Deserialize a string representing a non-negative integer into an `Option<u64>`. Returns `Some`
/// if successfully parses, and `None` otherwise.
pub(crate) fn parse_non_negative<T>(s: &str) -> Option<T>
where
    i64: TryInto<T>,
{
    // parse to i64 since java doesn't even allow u64
    let n: i64 = s.parse().ok().filter(|&i| i >= 0)?;
    n.try_into().ok()
}

/// Deserialize a string representing a boolean into an `Option<bool>`. Returns `Some` if
/// successfully parses, and `None` otherwise.
pub(crate) fn parse_bool(s: &str) -> Option<bool> {
    match s {
        "true" => Some(true),
        "false" => Some(false),
        _ => None,
    }
}

/// Deserialize a comma-separated list of column names into an `Option<Vec<ColumnName>>`. Returns
/// `Some` if successfully parses, and `None` otherwise.
pub(crate) fn parse_column_names(s: &str) -> Option<Vec<ColumnName>> {
    ColumnName::parse_column_name_list(s)
        .inspect_err(|e| warn!("column name list failed to parse: {e}"))
        .ok()
}

/// Deserialize an interval string of the form "interval 5 days" into an `Option<Duration>`.
/// Returns `Some` if successfully parses, and `None` otherwise.
pub(crate) fn parse_interval(s: &str) -> Option<Duration> {
    parse_interval_impl(s).ok()
}

#[derive(thiserror::Error, Debug)]
pub enum ParseIntervalError {
    /// The input string is not a valid interval
    #[error("'{0}' is not an interval")]
    NotAnInterval(String),
    /// Couldn't parse the input string as an integer
    #[error("Unable to parse '{0}' as an integer")]
    ParseIntError(String),
    /// Negative intervals aren't supported
    #[error("Interval '{0}' cannot be negative")]
    NegativeInterval(String),
    /// Unsupported interval
    #[error("Unsupported interval '{0}'")]
    UnsupportedInterval(String),
    /// Unknown unit
    #[error("Unknown interval unit '{0}'")]
    UnknownUnit(String),
}

/// This is effectively a simpler version of spark's `CalendarInterval` parser. See spark's
/// `stringToInterval`:
/// https://github.com/apache/spark/blob/5a57efdcee9e6569d8de4272bda258788cf349e3/sql/api/src/main/scala/org/apache/spark/sql/catalyst/util/SparkIntervalUtils.scala#L134
///
/// Notably we don't support months nor years, nor do we support fractional values, and negative
/// intervals aren't supported.
///
/// For now this is adapted from delta-rs' `parse_interval` function:
/// https://github.com/delta-io/delta-rs/blob/d4f18b3ae9d616e771b5d0e0fa498d0086fd91eb/crates/core/src/table/config.rs#L474
///
/// See issue delta-kernel-rs/#507 for details: https://github.com/delta-io/delta-kernel-rs/issues/507
fn parse_interval_impl(value: &str) -> Result<Duration, ParseIntervalError> {
    let mut it = value.split_whitespace();
    if it.next() != Some("interval") {
        return Err(ParseIntervalError::NotAnInterval(value.to_string()));
    }
    let number = it
        .next()
        .ok_or_else(|| ParseIntervalError::NotAnInterval(value.to_string()))?;
    let number: i64 = number
        .parse()
        .map_err(|_| ParseIntervalError::ParseIntError(number.into()))?;

    // TODO(zach): spark allows negative intervals, but we don't
    require!(
        number >= 0,
        ParseIntervalError::NegativeInterval(value.to_string())
    );

    // convert to u64 since Duration expects it
    let number = number as u64; // non-negative i64 => always safe

    let duration = match it
        .next()
        .ok_or_else(|| ParseIntervalError::NotAnInterval(value.to_string()))?
    {
        "nanosecond" | "nanoseconds" => Duration::from_nanos(number),
        "microsecond" | "microseconds" => Duration::from_micros(number),
        "millisecond" | "milliseconds" => Duration::from_millis(number),
        "second" | "seconds" => Duration::from_secs(number),
        "minute" | "minutes" => Duration::from_secs(number * SECONDS_PER_MINUTE),
        "hour" | "hours" => Duration::from_secs(number * SECONDS_PER_HOUR),
        "day" | "days" => Duration::from_secs(number * SECONDS_PER_DAY),
        "week" | "weeks" => Duration::from_secs(number * SECONDS_PER_WEEK),
        unit @ ("month" | "months") => {
            return Err(ParseIntervalError::UnsupportedInterval(unit.to_string()));
        }
        unit => {
            return Err(ParseIntervalError::UnknownUnit(unit.to_string()));
        }
    };

    Ok(duration)
}

#[cfg(test)]
mod tests {
    use ParquetCompressionCodec::*;

    use super::*;

    #[test]
    fn test_parse_bool() {
        assert!(parse_bool("true").unwrap());
        assert!(!parse_bool("false").unwrap());
        assert_eq!(parse_bool("whatever"), None);
    }

    #[test]
    fn test_parse_int() {
        assert_eq!(parse_positive_int("12").unwrap().get(), 12);
        assert_eq!(parse_positive_int("0"), None);
        assert_eq!(parse_positive_int("-12"), None);
        assert_eq!(parse_non_negative::<u64>("12").unwrap(), 12);
        assert_eq!(parse_non_negative::<u64>("0").unwrap(), 0);
        assert_eq!(parse_non_negative::<u64>("-12"), None);
        assert_eq!(parse_non_negative::<i64>("12").unwrap(), 12);
        assert_eq!(parse_non_negative::<i64>("0").unwrap(), 0);
        assert_eq!(parse_non_negative::<i64>("-12"), None);
    }

    #[test]
    fn test_parse_interval() {
        assert_eq!(
            parse_interval("interval 123 nanosecond").unwrap(),
            Duration::from_nanos(123)
        );

        assert_eq!(
            parse_interval("interval 123 nanoseconds").unwrap(),
            Duration::from_nanos(123)
        );

        assert_eq!(
            parse_interval("interval 123 microsecond").unwrap(),
            Duration::from_micros(123)
        );

        assert_eq!(
            parse_interval("interval 123 microseconds").unwrap(),
            Duration::from_micros(123)
        );

        assert_eq!(
            parse_interval("interval 123 millisecond").unwrap(),
            Duration::from_millis(123)
        );

        assert_eq!(
            parse_interval("interval 123 milliseconds").unwrap(),
            Duration::from_millis(123)
        );

        assert_eq!(
            parse_interval("interval 123 second").unwrap(),
            Duration::from_secs(123)
        );

        assert_eq!(
            parse_interval("interval 123 seconds").unwrap(),
            Duration::from_secs(123)
        );

        assert_eq!(
            parse_interval("interval 123 minute").unwrap(),
            Duration::from_secs(123 * 60)
        );

        assert_eq!(
            parse_interval("interval 123 minutes").unwrap(),
            Duration::from_secs(123 * 60)
        );

        assert_eq!(
            parse_interval("interval 123 hour").unwrap(),
            Duration::from_secs(123 * 3600)
        );

        assert_eq!(
            parse_interval("interval 123 hours").unwrap(),
            Duration::from_secs(123 * 3600)
        );

        assert_eq!(
            parse_interval("interval 123 day").unwrap(),
            Duration::from_secs(123 * 86400)
        );

        assert_eq!(
            parse_interval("interval 123 days").unwrap(),
            Duration::from_secs(123 * 86400)
        );

        assert_eq!(
            parse_interval("interval 123 week").unwrap(),
            Duration::from_secs(123 * 604800)
        );

        assert_eq!(
            parse_interval("interval 123 week").unwrap(),
            Duration::from_secs(123 * 604800)
        );
    }

    #[test]
    fn test_invalid_parse_interval() {
        assert_eq!(
            parse_interval_impl("whatever").err().unwrap().to_string(),
            "'whatever' is not an interval".to_string()
        );

        assert_eq!(
            parse_interval_impl("interval").err().unwrap().to_string(),
            "'interval' is not an interval".to_string()
        );

        assert_eq!(
            parse_interval_impl("interval 2").err().unwrap().to_string(),
            "'interval 2' is not an interval".to_string()
        );

        assert_eq!(
            parse_interval_impl("interval 2 months")
                .err()
                .unwrap()
                .to_string(),
            "Unsupported interval 'months'".to_string()
        );

        assert_eq!(
            parse_interval_impl("interval 2 years")
                .err()
                .unwrap()
                .to_string(),
            "Unknown interval unit 'years'".to_string()
        );

        assert_eq!(
            parse_interval_impl("interval two years")
                .err()
                .unwrap()
                .to_string(),
            "Unable to parse 'two' as an integer".to_string()
        );

        assert_eq!(
            parse_interval_impl("interval -25 hours")
                .err()
                .unwrap()
                .to_string(),
            "Interval 'interval -25 hours' cannot be negative".to_string()
        );
    }

    #[test]
    fn test_parse_compression_codec_accepts_all_variants_case_insensitively() {
        for (input, expected) in [
            ("uncompressed", Uncompressed),
            ("UNCOMPRESSED", Uncompressed),
            ("UnCoMpReSsEd", Uncompressed),
            ("none", Uncompressed),
            ("NONE", Uncompressed),
            ("nOnE", Uncompressed),
            ("snappy", Snappy),
            ("SNAPPY", Snappy),
            ("sNaPpY", Snappy),
            ("gzip", Gzip),
            ("GZIP", Gzip),
            ("gZiP", Gzip),
            ("lz4", Lz4),
            ("LZ4", Lz4),
            ("lZ4", Lz4),
            ("lz4_raw", Lz4Raw),
            ("LZ4_RAW", Lz4Raw),
            ("Lz4_Raw", Lz4Raw),
            ("zstd", Zstd),
            ("ZSTD", Zstd),
            ("zStD", Zstd),
        ] {
            let props = TableProperties::from([(PARQUET_COMPRESSION_CODEC, input)]);
            assert_eq!(props.parquet_compression_codec, Some(expected), "{input}");
            assert!(props.unknown_properties.is_empty(), "{input}");
        }
    }

    #[test]
    fn test_parse_compression_codec_unknown_falls_through_to_unknown_properties() {
        let props = TableProperties::from([(PARQUET_COMPRESSION_CODEC, "brotli")]);
        assert_eq!(props.parquet_compression_codec, None);
        assert_eq!(
            props.unknown_properties.get(PARQUET_COMPRESSION_CODEC),
            Some(&"brotli".to_string())
        );
    }

    #[test]
    fn test_compression_codec_round_trips_to_canonical_protocol_string() {
        // Each variant must Display-format to its Delta-protocol canonical name (lowercased,
        // snake_case). The `Uncompressed` variant has `none` as a parser-only alias; its
        // canonical output is `uncompressed`.
        for (variant, expected) in [
            (Zstd, "zstd"),
            (Uncompressed, "uncompressed"),
            (Snappy, "snappy"),
            (Gzip, "gzip"),
            (Lz4, "lz4"),
            (Lz4Raw, "lz4_raw"),
        ] {
            assert_eq!(variant.to_string(), expected);
            assert_eq!(<&'static str>::from(variant), expected);
            // And the canonical string parses back to the same variant.
            assert_eq!(
                ParquetCompressionCodec::try_from(expected).unwrap(),
                variant
            );
        }
    }

    #[test]
    fn test_compression_codec_or_default_falls_back_to_zstd_when_absent() {
        // Absent: applies the spec-recommended Zstd fallback.
        let props = TableProperties::default();
        assert_eq!(props.compression_codec_or_default(), Zstd);

        // Present: returns the parsed value as-is.
        let props = TableProperties::from([(PARQUET_COMPRESSION_CODEC, "snappy")]);
        assert_eq!(props.compression_codec_or_default(), Snappy);
    }
}