numcodecs_python/
adapter.rs

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
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
use std::sync::Arc;

use ndarray::{ArrayBase, DataMut, Dimension};
use numcodecs::{
    AnyArray, AnyArrayBase, AnyArrayView, AnyArrayViewMut, AnyCowArray, Codec, DynCodec,
    DynCodecType,
};
use numpy::{Element, PyArray, PyArrayDyn, PyArrayMethods, PyUntypedArray, PyUntypedArrayMethods};
use pyo3::{
    exceptions::{PyTypeError, PyValueError},
    intern,
    prelude::*,
    types::{IntoPyDict, PyDict, PyDictMethods},
};
use pythonize::{Depythonizer, Pythonizer};
use schemars::Schema;
use serde::{Deserializer, Serializer};
use serde_transcode::transcode;

use crate::{
    export::{RustCodec, RustCodecType},
    schema::schema_from_codec_class,
    PyCodec, PyCodecClass, PyCodecClassMethods, PyCodecMethods, PyCodecRegistry,
};

/// Wrapper around [`PyCodec`]s to use the [`Codec`] API.
pub struct PyCodecAdapter {
    codec: Py<PyCodec>,
    class: Py<PyCodecClass>,
    codec_id: Arc<String>,
    codec_config_schema: Arc<Schema>,
}

impl PyCodecAdapter {
    /// Instantiate a codec from the [`PyCodecRegistry`] with a serialized
    /// `config`uration.
    ///
    /// The config *must* include the `id` field with the
    /// [`PyCodecClassMethods::codec_id`].
    ///
    /// # Errors
    ///
    /// Errors if no codec with a matching `id` has been registered, or if
    /// constructing the codec fails.
    pub fn from_registry_with_config<'de, D: Deserializer<'de>>(
        config: D,
    ) -> Result<Self, D::Error> {
        Python::with_gil(|py| {
            let config = transcode(config, Pythonizer::new(py))?;
            let config: Bound<PyDict> = config.extract()?;

            let codec = PyCodecRegistry::get_codec(config.as_borrowed())?;

            Self::from_codec(codec)
        })
        .map_err(serde::de::Error::custom)
    }

    /// Wraps a [`PyCodec`] to use the [`Codec`] API.
    ///
    /// # Errors
    ///
    /// Errors if the `codec`'s class does not provide an identifier.
    pub fn from_codec(codec: Bound<PyCodec>) -> Result<Self, PyErr> {
        let class = codec.class();
        let codec_id = class.codec_id()?;
        let codec_config_schema = schema_from_codec_class(class.py(), &class).map_err(|err| {
            PyTypeError::new_err(format!(
                "failed to extract the {codec_id} codec config schema: {err}"
            ))
        })?;

        Ok(Self {
            codec: codec.unbind(),
            class: class.unbind(),
            codec_id: Arc::new(codec_id),
            codec_config_schema: Arc::new(codec_config_schema),
        })
    }

    /// Access the wrapped [`PyCodec`] to use its [`PyCodecMethods`] API.
    #[must_use]
    pub fn as_codec<'py>(&self, py: Python<'py>) -> &Bound<'py, PyCodec> {
        self.codec.bind(py)
    }

    /// Unwrap the [`PyCodec`] to use its [`PyCodecMethods`] API.
    #[must_use]
    pub fn into_codec(self, py: Python) -> Bound<PyCodec> {
        self.codec.into_bound(py)
    }

    /// Try to [`clone`][`Clone::clone`] this codec.
    ///
    /// # Errors
    ///
    /// Errors if extracting this codec's config or creating a new codec from
    /// the config fails.
    pub fn try_clone(&self, py: Python) -> Result<Self, PyErr> {
        let config = self.codec.bind(py).get_config()?;

        // removing the `id` field may fail if the config doesn't contain it
        let _ = config.del_item(intern!(py, "id"));

        let codec = self
            .class
            .bind(py)
            .codec_from_config(config.as_borrowed())?;

        Ok(Self {
            codec: codec.unbind(),
            class: self.class.clone_ref(py),
            codec_id: self.codec_id.clone(),
            codec_config_schema: self.codec_config_schema.clone(),
        })
    }

    /// If `codec` represents an exported [`DynCodec`] `T`, i.e. its class was
    /// initially created with [`crate::export_codec_class`], the `with` closure
    /// provides access to the instance of type `T`.
    ///
    /// If `codec` is not an instance of `T`, the `with` closure is *not* run
    /// and `None` is returned.
    pub fn with_downcast<T: DynCodec, O>(
        codec: &Bound<PyCodec>,
        with: impl for<'a> FnOnce(&'a T) -> O,
    ) -> Option<O> {
        let Ok(codec) = codec.downcast::<RustCodec>() else {
            return None;
        };

        let codec = codec.get().downcast()?;

        Some(with(codec))
    }
}

impl Codec for PyCodecAdapter {
    type Error = PyErr;

    fn encode(&self, data: AnyCowArray) -> Result<AnyArray, Self::Error> {
        Python::with_gil(|py| {
            self.with_any_array_view_as_ndarray(py, &data.view(), |data| {
                let encoded = self.codec.bind(py).encode(data.as_borrowed())?;

                Self::any_array_from_ndarray_like(py, encoded)
            })
        })
    }

    fn decode(&self, encoded: AnyCowArray) -> Result<AnyArray, Self::Error> {
        Python::with_gil(|py| {
            self.with_any_array_view_as_ndarray(py, &encoded.view(), |encoded| {
                let decoded = self.codec.bind(py).decode(encoded.as_borrowed(), None)?;

                Self::any_array_from_ndarray_like(py, decoded)
            })
        })
    }

    fn decode_into(
        &self,
        encoded: AnyArrayView,
        mut decoded: AnyArrayViewMut,
    ) -> Result<(), Self::Error> {
        Python::with_gil(|py| {
            let decoded_out = self.with_any_array_view_as_ndarray(py, &encoded, |encoded| {
                self.with_any_array_view_mut_as_ndarray(py, &mut decoded, |decoded_in| {
                    let decoded_out = self
                        .codec
                        .bind(py)
                        .decode(encoded.as_borrowed(), Some(decoded_in.as_borrowed()))?;

                    // Ideally, all codecs should just use the provided out array
                    if decoded_out.is(decoded_in) {
                        Ok(Ok(()))
                    } else {
                        Ok(Err(decoded_out.unbind()))
                    }
                })
            })?;
            let decoded_out = match decoded_out {
                Ok(()) => return Ok(()),
                Err(decoded_out) => decoded_out.into_bound(py),
            };

            // Otherwise, we force-copy the output into the decoded array
            Self::copy_into_any_array_view_mut_from_ndarray_like(py, &mut decoded, decoded_out)
        })
    }
}

impl PyCodecAdapter {
    fn with_any_array_view_as_ndarray<T>(
        &self,
        py: Python,
        view: &AnyArrayView,
        with: impl for<'a> FnOnce(&'a Bound<PyAny>) -> Result<T, PyErr>,
    ) -> Result<T, PyErr> {
        let this = self.codec.bind(py).clone().into_any();

        #[allow(unsafe_code)] // FIXME: we trust Python code to not store this array
        let ndarray = unsafe {
            match &view {
                AnyArrayBase::U8(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::U16(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::U32(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::U64(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::I8(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::I16(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::I32(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::I64(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::F32(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::F64(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                _ => {
                    return Err(PyTypeError::new_err(format!(
                        "unsupported type {} of read-only array view",
                        view.dtype()
                    )))
                }
            }
        };

        // create a fully-immutable view of the data that is safe to pass to Python
        ndarray.call_method(
            intern!(py, "setflags"),
            (),
            Some(&[(intern!(py, "write"), false)].into_py_dict_bound(py)),
        )?;
        let view = ndarray.call_method0(intern!(py, "view"))?;

        with(&view)
    }

    fn with_any_array_view_mut_as_ndarray<T>(
        &self,
        py: Python,
        view_mut: &mut AnyArrayViewMut,
        with: impl for<'a> FnOnce(&'a Bound<PyAny>) -> Result<T, PyErr>,
    ) -> Result<T, PyErr> {
        let this = self.codec.bind(py).clone().into_any();

        #[allow(unsafe_code)] // FIXME: we trust Python code to not store this array
        let ndarray = unsafe {
            match &view_mut {
                AnyArrayBase::U8(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::U16(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::U32(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::U64(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::I8(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::I16(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::I32(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::I64(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::F32(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                AnyArrayBase::F64(v) => PyArray::borrow_from_array_bound(v, this).into_any(),
                _ => {
                    return Err(PyTypeError::new_err(format!(
                        "unsupported type {} of read-only array view",
                        view_mut.dtype()
                    )))
                }
            }
        };

        with(&ndarray)
    }

    fn any_array_from_ndarray_like(
        py: Python,
        array_like: Bound<PyAny>,
    ) -> Result<AnyArray, PyErr> {
        let ndarray: Bound<PyUntypedArray> = py
            .import_bound(intern!(py, "numpy"))?
            .getattr(intern!(py, "asarray"))?
            .call1((array_like,))?
            .extract()?;

        let array = if let Ok(e) = ndarray.downcast::<PyArrayDyn<u8>>() {
            AnyArrayBase::U8(e.try_readonly()?.to_owned_array())
        } else if let Ok(e) = ndarray.downcast::<PyArrayDyn<u16>>() {
            AnyArrayBase::U16(e.try_readonly()?.to_owned_array())
        } else if let Ok(e) = ndarray.downcast::<PyArrayDyn<u32>>() {
            AnyArrayBase::U32(e.try_readonly()?.to_owned_array())
        } else if let Ok(e) = ndarray.downcast::<PyArrayDyn<u64>>() {
            AnyArrayBase::U64(e.try_readonly()?.to_owned_array())
        } else if let Ok(e) = ndarray.downcast::<PyArrayDyn<i8>>() {
            AnyArrayBase::I8(e.try_readonly()?.to_owned_array())
        } else if let Ok(e) = ndarray.downcast::<PyArrayDyn<i16>>() {
            AnyArrayBase::I16(e.try_readonly()?.to_owned_array())
        } else if let Ok(e) = ndarray.downcast::<PyArrayDyn<i32>>() {
            AnyArrayBase::I32(e.try_readonly()?.to_owned_array())
        } else if let Ok(e) = ndarray.downcast::<PyArrayDyn<i64>>() {
            AnyArrayBase::I64(e.try_readonly()?.to_owned_array())
        } else if let Ok(e) = ndarray.downcast::<PyArrayDyn<f32>>() {
            AnyArrayBase::F32(e.try_readonly()?.to_owned_array())
        } else if let Ok(e) = ndarray.downcast::<PyArrayDyn<f64>>() {
            AnyArrayBase::F64(e.try_readonly()?.to_owned_array())
        } else {
            return Err(PyTypeError::new_err(format!(
                "unsupported dtype {} of array-like",
                ndarray.dtype()
            )));
        };

        Ok(array)
    }

    fn copy_into_any_array_view_mut_from_ndarray_like(
        py: Python,
        view_mut: &mut AnyArrayViewMut,
        array_like: Bound<PyAny>,
    ) -> Result<(), PyErr> {
        fn shape_checked_assign<
            T: Copy + Element,
            S2: DataMut<Elem = T>,
            D1: Dimension,
            D2: Dimension,
        >(
            src: &Bound<PyArray<T, D1>>,
            dst: &mut ArrayBase<S2, D2>,
        ) -> Result<(), PyErr> {
            #[allow(clippy::unit_arg)]
            if src.shape() == dst.shape() {
                Ok(dst.assign(&src.try_readonly()?.as_array()))
            } else {
                Err(PyValueError::new_err(format!(
                    "mismatching shape {:?} of array-like, expected {:?}",
                    src.shape(),
                    dst.shape(),
                )))
            }
        }

        let ndarray: Bound<PyUntypedArray> = py
            .import_bound(intern!(py, "numpy"))?
            .getattr(intern!(py, "asarray"))?
            .call1((array_like,))?
            .extract()?;

        #[allow(clippy::unit_arg)]
        if let Ok(d) = ndarray.downcast::<PyArrayDyn<u8>>() {
            if let AnyArrayBase::U8(ref mut view_mut) = view_mut {
                return shape_checked_assign(d, view_mut);
            }
        } else if let Ok(d) = ndarray.downcast::<PyArrayDyn<u16>>() {
            if let AnyArrayBase::U16(ref mut view_mut) = view_mut {
                return shape_checked_assign(d, view_mut);
            }
        } else if let Ok(d) = ndarray.downcast::<PyArrayDyn<u32>>() {
            if let AnyArrayBase::U32(ref mut view_mut) = view_mut {
                return shape_checked_assign(d, view_mut);
            }
        } else if let Ok(d) = ndarray.downcast::<PyArrayDyn<u64>>() {
            if let AnyArrayBase::U64(ref mut view_mut) = view_mut {
                return shape_checked_assign(d, view_mut);
            }
        } else if let Ok(d) = ndarray.downcast::<PyArrayDyn<i8>>() {
            if let AnyArrayBase::I8(ref mut view_mut) = view_mut {
                return shape_checked_assign(d, view_mut);
            }
        } else if let Ok(d) = ndarray.downcast::<PyArrayDyn<i16>>() {
            if let AnyArrayBase::I16(ref mut view_mut) = view_mut {
                return shape_checked_assign(d, view_mut);
            }
        } else if let Ok(d) = ndarray.downcast::<PyArrayDyn<i32>>() {
            if let AnyArrayBase::I32(ref mut view_mut) = view_mut {
                return shape_checked_assign(d, view_mut);
            }
        } else if let Ok(d) = ndarray.downcast::<PyArrayDyn<i64>>() {
            if let AnyArrayBase::I64(ref mut view_mut) = view_mut {
                return shape_checked_assign(d, view_mut);
            }
        } else if let Ok(d) = ndarray.downcast::<PyArrayDyn<f32>>() {
            if let AnyArrayBase::F32(ref mut view_mut) = view_mut {
                return shape_checked_assign(d, view_mut);
            }
        } else if let Ok(d) = ndarray.downcast::<PyArrayDyn<f64>>() {
            if let AnyArrayBase::F64(ref mut view_mut) = view_mut {
                return shape_checked_assign(d, view_mut);
            }
        } else {
            return Err(PyTypeError::new_err(format!(
                "unsupported dtype {} of array-like",
                ndarray.dtype()
            )));
        };

        Err(PyTypeError::new_err(format!(
            "mismatching dtype {} of array-like, expected {}",
            ndarray.dtype(),
            view_mut.dtype(),
        )))
    }
}

impl Clone for PyCodecAdapter {
    fn clone(&self) -> Self {
        #[allow(clippy::expect_used)] // clone is *not* fallible
        Python::with_gil(|py| {
            self.try_clone(py)
                .expect("cloning a PyCodec should not fail")
        })
    }
}

impl DynCodec for PyCodecAdapter {
    type Type = PyCodecClassAdapter;

    fn ty(&self) -> Self::Type {
        Python::with_gil(|py| PyCodecClassAdapter {
            class: self.class.clone_ref(py),
            codec_id: self.codec_id.clone(),
            codec_config_schema: self.codec_config_schema.clone(),
        })
    }

    fn get_config<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
        Python::with_gil(|py| {
            let config = self
                .codec
                .bind(py)
                .get_config()
                .map_err(serde::ser::Error::custom)?;

            transcode(&mut Depythonizer::from_object(config.as_any()), serializer)
        })
    }
}

/// Wrapper around [`PyCodecClass`]es to use the [`DynCodecType`] API.
pub struct PyCodecClassAdapter {
    class: Py<PyCodecClass>,
    codec_id: Arc<String>,
    codec_config_schema: Arc<Schema>,
}

impl PyCodecClassAdapter {
    /// Wraps a [`PyCodecClass`] to use the [`DynCodecType`] API.
    ///
    /// # Errors
    ///
    /// Errors if the codec `class` does not provide an identifier.
    pub fn from_codec_class(class: Bound<PyCodecClass>) -> Result<Self, PyErr> {
        let codec_id = class.codec_id()?;

        let codec_config_schema = schema_from_codec_class(class.py(), &class).map_err(|err| {
            PyTypeError::new_err(format!(
                "failed to extract the {codec_id} codec config schema: {err}"
            ))
        })?;

        Ok(Self {
            class: class.unbind(),
            codec_id: Arc::new(codec_id),
            codec_config_schema: Arc::new(codec_config_schema),
        })
    }

    /// Access the wrapped [`PyCodecClass`] to use its [`PyCodecClassMethods`]
    /// API.
    #[must_use]
    pub fn as_codec_class<'py>(&self, py: Python<'py>) -> &Bound<'py, PyCodecClass> {
        self.class.bind(py)
    }

    /// Unwrap the [`PyCodecClass`] to use its [`PyCodecClassMethods`] API.
    #[must_use]
    pub fn into_codec_class(self, py: Python) -> Bound<PyCodecClass> {
        self.class.into_bound(py)
    }

    /// If `class` represents an exported [`DynCodecType`] `T`, i.e. it was
    /// initially created with [`crate::export_codec_class`], the `with` closure
    /// provides access to the instance of type `T`.
    ///
    /// If `class` is not an instance of `T`, the `with` closure is *not* run
    /// and `None` is returned.
    pub fn with_downcast<T: DynCodecType, O>(
        class: &Bound<PyCodecClass>,
        with: impl for<'a> FnOnce(&'a T) -> O,
    ) -> Option<O> {
        let Ok(ty) = class.getattr(intern!(class.py(), RustCodec::TYPE_ATTRIBUTE)) else {
            return None;
        };

        let Ok(ty) = ty.downcast_into_exact::<RustCodecType>() else {
            return None;
        };

        let ty: &T = ty.get().downcast()?;

        Some(with(ty))
    }
}

impl DynCodecType for PyCodecClassAdapter {
    type Codec = PyCodecAdapter;

    fn codec_id(&self) -> &str {
        &self.codec_id
    }

    fn codec_config_schema(&self) -> Schema {
        (*self.codec_config_schema).clone()
    }

    fn codec_from_config<'de, D: Deserializer<'de>>(
        &self,
        config: D,
    ) -> Result<Self::Codec, D::Error> {
        Python::with_gil(|py| {
            let config =
                transcode(config, Pythonizer::new(py)).map_err(serde::de::Error::custom)?;
            let config: Bound<PyDict> = config.extract().map_err(serde::de::Error::custom)?;

            let codec = self
                .class
                .bind(py)
                .codec_from_config(config.as_borrowed())
                .map_err(serde::de::Error::custom)?;

            Ok(PyCodecAdapter {
                codec: codec.unbind(),
                class: self.class.clone_ref(py),
                codec_id: self.codec_id.clone(),
                codec_config_schema: self.codec_config_schema.clone(),
            })
        })
    }
}