# -*- coding: utf-8 -*- # # Copyright (C) 2016 Andi Albrecht, albrecht.andi@gmail.com # # This module is part of python-sqlparse and is released under # the BSD License: https://opensource.org/licenses/BSD-3-Clause """This module contains classes representing syntactical elements of SQL.""" from __future__ import print_function import re from sqlparse import tokens as T from sqlparse.compat import string_types, text_type, unicode_compatible from sqlparse.utils import imt, remove_quotes @unicode_compatible class Token(object): """Base class for all other classes in this module. It represents a single token and has two instance attributes: ``value`` is the unchange value of the token and ``ttype`` is the type of the token. """ __slots__ = ('value', 'ttype', 'parent', 'normalized', 'is_keyword', 'is_group', 'is_whitespace') def __init__(self, ttype, value): value = text_type(value) self.value = value self.ttype = ttype self.parent = None self.is_group = False self.is_keyword = ttype in T.Keyword self.is_whitespace = self.ttype in T.Whitespace self.normalized = value.upper() if self.is_keyword else value def __str__(self): return self.value # Pending tokenlist __len__ bug fix # def __len__(self): # return len(self.value) def __repr__(self): cls = self._get_repr_name() value = self._get_repr_value() q = u'"' if value.startswith("'") and value.endswith("'") else u"'" return u"<{cls} {q}{value}{q} at 0x{id:2X}>".format( id=id(self), **locals()) def _get_repr_name(self): return str(self.ttype).split('.')[-1] def _get_repr_value(self): raw = text_type(self) if len(raw) > 7: raw = raw[:6] + '...' return re.sub(r'\s+', ' ', raw) def flatten(self): """Resolve subgroups.""" yield self def match(self, ttype, values, regex=False): """Checks whether the token matches the given arguments. *ttype* is a token type. If this token doesn't match the given token type. *values* is a list of possible values for this token. The values are OR'ed together so if only one of the values matches ``True`` is returned. Except for keyword tokens the comparison is case-sensitive. For convenience it's ok to pass in a single string. If *regex* is ``True`` (default is ``False``) the given values are treated as regular expressions. """ type_matched = self.ttype is ttype if not type_matched or values is None: return type_matched if isinstance(values, string_types): values = (values,) if regex: # TODO: Add test for regex with is_keyboard = false flag = re.IGNORECASE if self.is_keyword else 0 values = (re.compile(v, flag) for v in values) for pattern in values: if pattern.search(self.normalized): return True return False if self.is_keyword: values = (v.upper() for v in values) return self.normalized in values def within(self, group_cls): """Returns ``True`` if this token is within *group_cls*. Use this method for example to check if an identifier is within a function: ``t.within(sql.Function)``. """ parent = self.parent while parent: if isinstance(parent, group_cls): return True parent = parent.parent return False def is_child_of(self, other): """Returns ``True`` if this token is a direct child of *other*.""" return self.parent == other def has_ancestor(self, other): """Returns ``True`` if *other* is in this tokens ancestry.""" parent = self.parent while parent: if parent == other: return True parent = parent.parent return False @unicode_compatible class TokenList(Token): """A group of tokens. It has an additional instance attribute ``tokens`` which holds a list of child-tokens. """ __slots__ = 'tokens' def __init__(self, tokens=None): self.tokens = tokens or [] [setattr(token, 'parent', self) for token in tokens] super(TokenList, self).__init__(None, text_type(self)) self.is_group = True def __str__(self): return u''.join(token.value for token in self.flatten()) # weird bug # def __len__(self): # return len(self.tokens) def __iter__(self): return iter(self.tokens) def __getitem__(self, item): return self.tokens[item] def _get_repr_name(self): return type(self).__name__ def _pprint_tree(self, max_depth=None, depth=0, f=None): """Pretty-print the object tree.""" indent = u' | ' * depth for idx, token in enumerate(self.tokens): cls = token._get_repr_name() value = token._get_repr_value() q = u'"' if value.startswith("'") and value.endswith("'") else u"'" print(u"{indent}{idx:2d} {cls} {q}{value}{q}" .format(**locals()), file=f) if token.is_group and (max_depth is None or depth < max_depth): token._pprint_tree(max_depth, depth + 1, f) def get_token_at_offset(self, offset): """Returns the token that is on position offset.""" idx = 0 for token in self.flatten(): end = idx + len(token.value) if idx <= offset < end: return token idx = end def flatten(self): """Generator yielding ungrouped tokens. This method is recursively called for all child tokens. """ for token in self.tokens: if token.is_group: for item in token.flatten(): yield item else: yield token def get_sublists(self): for token in self.tokens: if token.is_group: yield token @property def _groupable_tokens(self): return self.tokens def _token_matching(self, funcs, start=0, end=None, reverse=False): """next token that match functions""" if start is None: return None if not isinstance(funcs, (list, tuple)): funcs = (funcs,) if reverse: assert end is None for idx in range(start - 2, -1, -1): token = self.tokens[idx] for func in funcs: if func(token): return idx, token else: for idx, token in enumerate(self.tokens[start:end], start=start): for func in funcs: if func(token): return idx, token return None, None def token_first(self, skip_ws=True, skip_cm=False): """Returns the first child token. If *skip_ws* is ``True`` (the default), whitespace tokens are ignored. if *skip_cm* is ``True`` (default: ``False``), comments are ignored too. """ # this on is inconsistent, using Comment instead of T.Comment... funcs = lambda tk: not ((skip_ws and tk.is_whitespace) or (skip_cm and imt(tk, t=T.Comment, i=Comment))) return self._token_matching(funcs)[1] def token_next_by(self, i=None, m=None, t=None, idx=-1, end=None): funcs = lambda tk: imt(tk, i, m, t) idx += 1 return self._token_matching(funcs, idx, end) def token_not_matching(self, funcs, idx): funcs = (funcs,) if not isinstance(funcs, (list, tuple)) else funcs funcs = [lambda tk: not func(tk) for func in funcs] return self._token_matching(funcs, idx) def token_matching(self, funcs, idx): return self._token_matching(funcs, idx)[1] def token_prev(self, idx, skip_ws=True, skip_cm=False): """Returns the previous token relative to *idx*. If *skip_ws* is ``True`` (the default) whitespace tokens are ignored. If *skip_cm* is ``True`` comments are ignored. ``None`` is returned if there's no previous token. """ return self.token_next(idx, skip_ws, skip_cm, _reverse=True) # TODO: May need to re-add default value to idx def token_next(self, idx, skip_ws=True, skip_cm=False, _reverse=False): """Returns the next token relative to *idx*. If *skip_ws* is ``True`` (the default) whitespace tokens are ignored. If *skip_cm* is ``True`` comments are ignored. ``None`` is returned if there's no next token. """ if idx is None: return None, None idx += 1 # alot of code usage current pre-compensates for this funcs = lambda tk: not ((skip_ws and tk.is_whitespace) or (skip_cm and imt(tk, t=T.Comment, i=Comment))) return self._token_matching(funcs, idx, reverse=_reverse) def token_index(self, token, start=0): """Return list index of token.""" start = start if isinstance(start, int) else self.token_index(start) return start + self.tokens[start:].index(token) def group_tokens(self, grp_cls, start, end, include_end=True, extend=False): """Replace tokens by an instance of *grp_cls*.""" start_idx = start start = self.tokens[start_idx] end_idx = end + include_end # will be needed later for new group_clauses # while skip_ws and tokens and tokens[-1].is_whitespace: # tokens = tokens[:-1] if extend and isinstance(start, grp_cls): subtokens = self.tokens[start_idx + 1:end_idx] grp = start grp.tokens.extend(subtokens) del self.tokens[start_idx + 1:end_idx] grp.value = text_type(start) else: subtokens = self.tokens[start_idx:end_idx] grp = grp_cls(subtokens) self.tokens[start_idx:end_idx] = [grp] grp.parent = self for token in subtokens: token.parent = grp return grp def insert_before(self, where, token): """Inserts *token* before *where*.""" if not isinstance(where, int): where = self.token_index(where) token.parent = self self.tokens.insert(where, token) def insert_after(self, where, token, skip_ws=True): """Inserts *token* after *where*.""" if not isinstance(where, int): where = self.token_index(where) nidx, next_ = self.token_next(where, skip_ws=skip_ws) token.parent = self if next_ is None: self.tokens.append(token) else: self.tokens.insert(nidx, token) def has_alias(self): """Returns ``True`` if an alias is present.""" return self.get_alias() is not None def get_alias(self): """Returns the alias for this identifier or ``None``.""" # "name AS alias" kw_idx, kw = self.token_next_by(m=(T.Keyword, 'AS')) if kw is not None: return self._get_first_name(kw_idx + 1, keywords=True) # "name alias" or "complicated column expression alias" _, ws = self.token_next_by(t=T.Whitespace) if len(self.tokens) > 2 and ws is not None: return self._get_first_name(reverse=True) def get_name(self): """Returns the name of this identifier. This is either it's alias or it's real name. The returned valued can be considered as the name under which the object corresponding to this identifier is known within the current statement. """ return self.get_alias() or self.get_real_name() def get_real_name(self): """Returns the real name (object name) of this identifier.""" # a.b dot_idx, _ = self.token_next_by(m=(T.Punctuation, '.')) return self._get_first_name(dot_idx) def get_parent_name(self): """Return name of the parent object if any. A parent object is identified by the first occuring dot. """ dot_idx, _ = self.token_next_by(m=(T.Punctuation, '.')) _, prev_ = self.token_prev(dot_idx) return remove_quotes(prev_.value) if prev_ is not None else None def _get_first_name(self, idx=None, reverse=False, keywords=False): """Returns the name of the first token with a name""" tokens = self.tokens[idx:] if idx else self.tokens tokens = reversed(tokens) if reverse else tokens types = [T.Name, T.Wildcard, T.String.Symbol] if keywords: types.append(T.Keyword) for token in tokens: if token.ttype in types: return remove_quotes(token.value) elif isinstance(token, (Identifier, Function)): return token.get_name() class Statement(TokenList): """Represents a SQL statement.""" def get_type(self): """Returns the type of a statement. The returned value is a string holding an upper-cased reprint of the first DML or DDL keyword. If the first token in this group isn't a DML or DDL keyword "UNKNOWN" is returned. Whitespaces and comments at the beginning of the statement are ignored. """ first_token = self.token_first(skip_cm=True) if first_token is None: # An "empty" statement that either has not tokens at all # or only whitespace tokens. return 'UNKNOWN' elif first_token.ttype in (T.Keyword.DML, T.Keyword.DDL): return first_token.normalized elif first_token.ttype == T.Keyword.CTE: # The WITH keyword should be followed by either an Identifier or # an IdentifierList containing the CTE definitions; the actual # DML keyword (e.g. SELECT, INSERT) will follow next. fidx = self.token_index(first_token) tidx, token = self.token_next(fidx, skip_ws=True) if isinstance(token, (Identifier, IdentifierList)): _, dml_keyword = self.token_next(tidx, skip_ws=True) if dml_keyword.ttype == T.Keyword.DML: return dml_keyword.normalized # Hmm, probably invalid syntax, so return unknown. return 'UNKNOWN' class Identifier(TokenList): """Represents an identifier. Identifiers may have aliases or typecasts. """ def is_wildcard(self): """Return ``True`` if this identifier contains a wildcard.""" _, token = self.token_next_by(t=T.Wildcard) return token is not None def get_typecast(self): """Returns the typecast or ``None`` of this object as a string.""" midx, marker = self.token_next_by(m=(T.Punctuation, '::')) nidx, next_ = self.token_next(midx, skip_ws=False) return next_.value if next_ else None def get_ordering(self): """Returns the ordering or ``None`` as uppercase string.""" _, ordering = self.token_next_by(t=T.Keyword.Order) return ordering.normalized if ordering else None def get_array_indices(self): """Returns an iterator of index token lists""" for token in self.tokens: if isinstance(token, SquareBrackets): # Use [1:-1] index to discard the square brackets yield token.tokens[1:-1] class IdentifierList(TokenList): """A list of :class:`~sqlparse.sql.Identifier`\'s.""" def get_identifiers(self): """Returns the identifiers. Whitespaces and punctuations are not included in this generator. """ for token in self.tokens: if not (token.is_whitespace or token.match(T.Punctuation, ',')): yield token class Parenthesis(TokenList): """Tokens between parenthesis.""" M_OPEN = T.Punctuation, '(' M_CLOSE = T.Punctuation, ')' @property def _groupable_tokens(self): return self.tokens[1:-1] class SquareBrackets(TokenList): """Tokens between square brackets""" M_OPEN = T.Punctuation, '[' M_CLOSE = T.Punctuation, ']' @property def _groupable_tokens(self): return self.tokens[1:-1] class Assignment(TokenList): """An assignment like 'var := val;'""" class If(TokenList): """An 'if' clause with possible 'else if' or 'else' parts.""" M_OPEN = T.Keyword, 'IF' M_CLOSE = T.Keyword, 'END IF' class For(TokenList): """A 'FOR' loop.""" M_OPEN = T.Keyword, ('FOR', 'FOREACH') M_CLOSE = T.Keyword, 'END LOOP' class Comparison(TokenList): """A comparison used for example in WHERE clauses.""" @property def left(self): return self.tokens[0] @property def right(self): return self.tokens[-1] class Comment(TokenList): """A comment.""" def is_multiline(self): return self.tokens and self.tokens[0].ttype == T.Comment.Multiline class Where(TokenList): """A WHERE clause.""" M_OPEN = T.Keyword, 'WHERE' M_CLOSE = T.Keyword, ( 'ORDER', 'GROUP', 'LIMIT', 'UNION', 'UNION ALL', 'EXCEPT', 'HAVING', 'RETURNING', 'INTO') class Case(TokenList): """A CASE statement with one or more WHEN and possibly an ELSE part.""" M_OPEN = T.Keyword, 'CASE' M_CLOSE = T.Keyword, 'END' def get_cases(self, skip_ws=False): """Returns a list of 2-tuples (condition, value). If an ELSE exists condition is None. """ CONDITION = 1 VALUE = 2 ret = [] mode = CONDITION for token in self.tokens: # Set mode from the current statement if token.match(T.Keyword, 'CASE'): continue elif skip_ws and token.ttype in T.Whitespace: continue elif token.match(T.Keyword, 'WHEN'): ret.append(([], [])) mode = CONDITION elif token.match(T.Keyword, 'THEN'): mode = VALUE elif token.match(T.Keyword, 'ELSE'): ret.append((None, [])) mode = VALUE elif token.match(T.Keyword, 'END'): mode = None # First condition without preceding WHEN if mode and not ret: ret.append(([], [])) # Append token depending of the current mode if mode == CONDITION: ret[-1][0].append(token) elif mode == VALUE: ret[-1][1].append(token) # Return cases list return ret class Function(TokenList): """A function or procedure call.""" def get_parameters(self): """Return a list of parameters.""" parenthesis = self.tokens[-1] for token in parenthesis.tokens: if isinstance(token, IdentifierList): return token.get_identifiers() elif imt(token, i=(Function, Identifier), t=T.Literal): return [token, ] return [] class Begin(TokenList): """A BEGIN/END block.""" M_OPEN = T.Keyword, 'BEGIN' M_CLOSE = T.Keyword, 'END' class Operation(TokenList): """Grouping of operations"""