Source

htsql-charset-option / src / htsql / tr / binder.py

Full commit
  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
#
# Copyright (c) 2006-2010, Prometheus Research, LLC
# Authors: Clark C. Evans <cce@clarkevans.com>,
#          Kirill Simonov <xi@resolvent.net>
#


"""
:mod:`htsql.tr.binder`
======================

This module implements binding adapters.
"""


from ..adapter import Adapter, adapts, find_adapters
from .syntax import (Syntax, QuerySyntax, SegmentSyntax, SelectorSyntax,
                     SieveSyntax, OperatorSyntax, FunctionOperatorSyntax,
                     FunctionCallSyntax, GroupSyntax, SpecifierSyntax,
                     IdentifierSyntax, WildcardSyntax, StringSyntax,
                     NumberSyntax)
from .binding import (Binding, RootBinding, QueryBinding, SegmentBinding,
                      TableBinding, FreeTableBinding, JoinedTableBinding,
                      ColumnBinding, LiteralBinding, SieveBinding,
                      CastBinding, TupleBinding)
from .lookup import Lookup
from .fn.function import FindFunction
from ..introspect import Introspect
from ..domain import (Domain, BooleanDomain, IntegerDomain, DecimalDomain,
                      FloatDomain, StringDomain, DateDomain,
                      TupleDomain, UntypedDomain, VoidDomain)
from ..error import InvalidArgumentError
from ..context import context
import decimal


class Binder(object):

    def bind(self, syntax, parent=None):
        if parent is None:
            app = context.app
            if app.cached_catalog is None:
                introspect = Introspect()
                catalog = introspect()
                app.cached_catalog = catalog
            catalog = app.cached_catalog
            parent = RootBinding(catalog, syntax)
        bind = Bind(syntax, self)
        return bind.bind(parent)

    def bind_one(self, syntax, parent=None):
        if parent is None:
            app = context.app
            if app.cached_catalog is None:
                introspect = Introspect()
                catalog = introspect()
                app.cached_catalog = catalog
            catalog = app.cached_catalog
            parent = RootBinding(catalog, syntax)
        bind = Bind(syntax, self)
        return bind.bind_one(parent)

    def find_function(self, name):
        find_function = FindFunction()
        return find_function(name, self)

    def cast(self, binding, domain, syntax=None, parent=None):
        if syntax is None:
            syntax = binding.syntax
        if parent is None:
            parent = binding.parent
        cast = Cast(binding, binding.domain, domain, self)
        return cast.cast(syntax, parent)

    def coerce(self, left_domain, right_domain=None):
        if right_domain is not None:
            coerce = BinaryCoerce(left_domain, right_domain)
            domain = coerce()
            if domain is None:
                coerce = BinaryCoerce(right_domain, left_domain)
                domain = coerce()
            return domain
        else:
            coerce = UnaryCoerce(left_domain)
            return coerce()


class UnaryCoerce(Adapter):

    adapts(Domain)

    def __init__(self, domain):
        self.domain = domain

    def __call__(self):
        return self.domain


class CoerceVoid(UnaryCoerce):

    adapts(VoidDomain)

    def __call__(self):
        return None


class CoerceTuple(UnaryCoerce):

    adapts(TupleDomain)

    def __call__(self):
        return None


class CoerceUntyped(UnaryCoerce):

    adapts(UntypedDomain)

    def __call__(self):
        return StringDomain()


class BinaryCoerce(Adapter):

    adapts(Domain, Domain)

    def __init__(self, left_domain, right_domain):
        self.left_domain = left_domain
        self.right_domain = right_domain

    def __call__(self):
        return None


class BinaryCoerceUntyped(BinaryCoerce):

    adapts(Domain, UntypedDomain)

    def __call__(self):
        return self.left_domain


class BinaryCoerceBoolean(BinaryCoerce):

    adapts(BooleanDomain, BooleanDomain)

    def __call__(self):
        return BooleanDomain()


class BinaryCoerceInteger(BinaryCoerce):

    adapts(IntegerDomain, IntegerDomain)

    def __call__(self):
        return IntegerDomain()


class BinaryCoerceFloat(BinaryCoerce):

    adapts(FloatDomain, FloatDomain)

    def __call__(self):
        return FloatDomain()


class BinaryCoerceDecimal(BinaryCoerce):

    adapts(DecimalDomain, DecimalDomain)

    def __call__(self):
        return DecimalDomain()


class BinaryCoerceString(BinaryCoerce):

    adapts(StringDomain, StringDomain)

    def __call__(self):
        return StringDomain()


class BinaryCoerceDate(BinaryCoerce):

    adapts(DateDomain, DateDomain)

    def __call__(self):
        return DateDomain()


class CoerceIntegerToDecimal(BinaryCoerce):

    adapts(IntegerDomain, DecimalDomain)

    def __call__(self):
        return DecimalDomain()


class CoerceIntegerToFloat(BinaryCoerce):

    adapts(IntegerDomain, FloatDomain)

    def __call__(self):
        return FloatDomain()


class CoerceDecimalToFloat(BinaryCoerce):

    adapts(DecimalDomain, FloatDomain)

    def __call__(self):
        return FloatDomain()


class Cast(Adapter):

    adapts(Binding, Domain, Domain, Binder)

    def __init__(self, binding, from_domain, to_domain, binder):
        self.binding = binding
        self.from_domain = from_domain
        self.to_domain = to_domain
        self.binder = binder

    def cast(self, syntax, parent):
        return CastBinding(parent, self.binding, self.to_domain, syntax)


class CastBooleanToBoolean(Cast):

    adapts(Binding, BooleanDomain, BooleanDomain, Binder)

    def cast(self, syntax, parent):
        return self.binding


class CastTupleToBoolean(Cast):

    adapts(Binding, TupleDomain, BooleanDomain, Binder)

    def cast(self, syntax, parent):
        return TupleBinding(self.binding)


class CastStringToString(Cast):

    adapts(Binding, StringDomain, StringDomain, Binder)

    def cast(self, syntax, parent):
        return self.binding


class CastIntegerToInteger(Cast):

    adapts(Binding, IntegerDomain, IntegerDomain, Binder)

    def cast(self, syntax, parent):
        return self.binding


class CastDecimalToDecimal(Cast):

    adapts(Binding, DecimalDomain, DecimalDomain, Binder)

    def cast(self, syntax, parent):
        return self.binding


class CastFloatToFloat(Cast):

    adapts(Binding, FloatDomain, FloatDomain, Binder)

    def cast(self, syntax, parent):
        return self.binding


class CastDateToDate(Cast):

    adapts(Binding, DateDomain, DateDomain, Binder)

    def cast(self, syntax, parent):
        return self.binding


class CastLiteral(Cast):

    adapts(LiteralBinding, UntypedDomain, Domain, Binder)

    def cast(self, syntax, parent):
        try:
            value = self.to_domain.parse(self.binding.value)
        except ValueError, exc:
            raise InvalidArgumentError("cannot cast a value: %s" % exc,
                                       syntax.mark)
        return LiteralBinding(parent, value, self.to_domain, syntax)


class Bind(Adapter):

    adapts(Syntax, Binder)

    def __init__(self, syntax, binder):
        self.syntax = syntax
        self.binder = binder

    def bind(self, parent):
        raise InvalidArgumentError("unable to bind a node", self.syntax.mark)

    def bind_one(self, parent):
        bindings = list(self.bind(parent))
        if len(bindings) == 1:
            return bindings[0]
        if len(bindings) < 1:
            raise InvalidArgumentError("expected one node; got none",
                                       self.syntax.mark)
        if len(bindings) > 1:
            raise InvalidArgumentError("expected one node; got more",
                                       self.syntax.mark)


class BindQuery(Bind):

    adapts(QuerySyntax, Binder)

    def bind(self, parent):
        segment = None
        if self.syntax.segment is not None:
            segment = self.binder.bind_one(self.syntax.segment, parent)
        yield QueryBinding(parent, segment, self.syntax)


class BindSegment(Bind):

    adapts(SegmentSyntax, Binder)

    def bind(self, parent):
        base = parent
        if self.syntax.base is not None:
            base = self.binder.bind_one(self.syntax.base, base)
        if self.syntax.filter is not None:
            filter = self.binder.bind_one(self.syntax.filter, base)
            base_syntax = SieveSyntax(base.syntax, None, filter.syntax,
                                      base.mark)
            base_syntax = GroupSyntax(base_syntax, base.mark)
            base = SieveBinding(base, filter, base_syntax)
        if self.syntax.selector is not None:
            bare_elements = list(self.binder.bind(self.syntax.selector, base))
        else:
            lookup = Lookup(base)
            bare_elements = list(lookup.enumerate(base.syntax))
        elements = []
        for element in bare_elements:
            domain = self.binder.coerce(element.domain)
            if domain is None:
                raise InvalidArgumentError("invalid type", element.mark)
            if domain is not element.domain:
                element = self.binder.cast(element, domain)
            elements.append(element)
        yield SegmentBinding(parent, base, elements, self.syntax)


class BindSelector(Bind):

    adapts(SelectorSyntax, Binder)

    def bind(self, parent):
        for element in self.syntax.elements:
            for binding in self.binder.bind(element, parent):
                yield binding


class BindSieve(Bind):

    adapts(SieveSyntax, Binder)

    def bind(self, parent):
        base = self.binder.bind_one(self.syntax.base, parent)
        if self.syntax.filter is not None:
            filter = self.binder.bind_one(self.syntax.filter, base)
            base_syntax = SieveSyntax(base.syntax, None, filter.syntax,
                                      base.mark)
            if self.syntax.selector is not None:
                base_syntax = GroupSyntax(base_syntax, base.mark)
            base = SieveBinding(base, filter, base_syntax)
        if self.syntax.selector is not None:
            for binding in self.binder.bind(self.syntax.selector, base):
                selector = SelectorSyntax([binding.syntax], binding.mark)
                binding_syntax = SieveSyntax(self.syntax.base,
                                             selector,
                                             self.syntax.filter,
                                             binding.mark)
                binding = binding.clone(syntax=binding_syntax)
                yield binding
        else:
            yield base


class BindOperator(Bind):

    adapts(OperatorSyntax, Binder)

    def bind(self, parent):
        name = self.syntax.symbol
        if self.syntax.left is not None:
            name = '_'+name
        if self.syntax.right is not None:
            name = name+'_'
        function = self.binder.find_function(name)
        return function.bind_operator(self.syntax, parent)


class BindFunctionOperator(Bind):

    adapts(FunctionOperatorSyntax, Binder)

    def bind(self, parent):
        name = self.syntax.identifier.value
        function = self.binder.find_function(name)
        return function.bind_function_operator(self.syntax, parent)


class BindFunctionCall(Bind):

    adapts(FunctionCallSyntax, Binder)

    def bind(self, parent):
        if self.syntax.base is not None:
            parent = self.binder.bind_one(self.syntax.base)
        name = self.syntax.identifier.value
        function = self.binder.find_function(name)
        return function.bind_function_call(self.syntax, parent)


class BindGroup(Bind):

    adapts(GroupSyntax, Binder)

    def bind(self, parent):
        for binding in self.binder.bind(self.syntax.expression, parent):
            binding_syntax = GroupSyntax(binding.syntax, binding.mark)
            binding = binding.clone(syntax=binding_syntax)
            yield binding


class BindSpecifier(Bind):

    adapts(SpecifierSyntax, Binder)

    def bind(self, parent):
        base = self.binder.bind_one(self.syntax.base, parent)
        for binding in self.binder.bind(self.syntax.identifier, base):
            binding_syntax = SpecifierSyntax(base.syntax, binding.syntax,
                                             binding.mark)
            binding = binding.clone(syntax=binding_syntax)
            yield binding


class BindIdentifier(Bind):

    adapts(IdentifierSyntax, Binder)

    def bind(self, parent):
        lookup = Lookup(parent)
        binding = lookup(self.syntax)
        yield binding


class BindWildcard(Bind):

    adapts(WildcardSyntax, Binder)

    def bind(self, parent):
        lookup = Lookup(parent)
        for binding in lookup.enumerate(self.syntax):
            yield binding


class BindString(Bind):

    adapts(StringSyntax, Binder)

    def bind(self, parent):
        binding = LiteralBinding(parent, self.syntax.value,
                                 UntypedDomain(),
                                 self.syntax)
        yield binding


class BindNumber(Bind):

    adapts(NumberSyntax, Binder)

    def bind(self, parent):
        value = self.syntax.value
        if 'e' in value or 'E' in value:
            domain = FloatDomain()
            value = float(value)
        elif '.' in value:
            domain = DecimalDomain()
            value = decimal.Decimal(value)
        else:
            domain = IntegerDomain()
            value = int(value)
        binding = LiteralBinding(parent, value, domain, self.syntax)
        yield binding


bind_adapters = find_adapters()