| | 1 | r""" |
| | 2 | Contains tools to massage sql text. |
| | 3 | |
| | 4 | #>>> re.findall( r'(?<!\%)(\%)(?!\%)', ' %a%% ' ) |
| | 5 | |
| | 6 | |
| | 7 | """ |
| | 8 | import re |
| | 9 | |
| | 10 | _single_or_stmtend = r"(?P<semi>\;)|(?P<comment>\-\-)|(?P<ccomment>\/\*)|(?P<endccomment>\*\/)|(?P<lineend>\n|\r$)|(?P<firstquo>^\')|(?P<escquo>\'\')|(?:(?P<midquo>\')(?!\'))" |
| | 11 | _dollarq = r"(?P<dollarquo>\$\w*\$)" |
| | 12 | _percent = r"(?<!\%)\%(?!\%)" |
| | 13 | |
| | 14 | _single_id_re = re.compile( _single_or_stmtend ) |
| | 15 | _id_re = re.compile( '|'.join( ( _single_or_stmtend, _dollarq ) ) ) |
| | 16 | _percent_re = re.compile( _percent ) |
| | 17 | |
| | 18 | def sql_statement_iterator( |
| | 19 | script, dollar_quotes = True, double_percent_signs = False |
| | 20 | ): |
| | 21 | r""" |
| | 22 | Iterate through the statements in an sql script, |
| | 23 | while respecting the boundaries of strings and comments. |
| | 24 | |
| | 25 | Supports normal single quotes, dollar_quotes (unless turned off). |
| | 26 | Supports normal sql comments, and c-style comments |
| | 27 | If 'double_percent_signs' is specified, standalone percent signs |
| | 28 | will be doubled. This is useful when no parameters are intended, |
| | 29 | as otherwise python db api treats them as substitution points. |
| | 30 | |
| | 31 | |
| | 32 | Test various quirks of quotes: |
| | 33 | |
| | 34 | >>> def show( s, **kw ): |
| | 35 | ... for line in sql_statement_iterator( s, **kw ): |
| | 36 | ... print line |
| | 37 | |
| | 38 | >>> show( 'this is a \'simple;\'; test' ) |
| | 39 | this is a 'simple;'; |
| | 40 | test |
| | 41 | >>> show( ';' ) |
| | 42 | ; |
| | 43 | >>> show( 'let\'s test a $DOLLAR$ quoted; $DOLLAR$ string' ) |
| | 44 | let's test a $DOLLAR$ quoted; $DOLLAR$ string |
| | 45 | |
| | 46 | >>> show( 'testing $$ nested; $A$ quotes; \'with;\' $A$;$$ many; fake; semicolons;' ) |
| | 47 | testing $$ nested; $A$ quotes; 'with;' $A$;$$ many; |
| | 48 | fake; |
| | 49 | semicolons; |
| | 50 | |
| | 51 | >>> show( '''nested misformed $$ quote's $$; dont; cause; problems;''' ) |
| | 52 | nested misformed $$ quote's $$; |
| | 53 | dont; |
| | 54 | cause; |
| | 55 | problems; |
| | 56 | |
| | 57 | A real function: |
| | 58 | |
| | 59 | >>> show( '''CREATE OR REPLACE FUNCTION serviceIsCurrent( srow client_service ) |
| | 60 | ... RETURNS bool LANGUAGE PLPGSQL AS $BODY$ |
| | 61 | ... BEGIN |
| | 62 | ... RETURN srow.start <= current_date AND ( |
| | 63 | ... srow.end IS NULL OR srow.end >= current_date ) AND |
| | 64 | ... srow."_superceededBy_id" IS NULL; |
| | 65 | ... END; |
| | 66 | ... $BODY$; |
| | 67 | ... ''' ) |
| | 68 | CREATE OR REPLACE FUNCTION serviceIsCurrent( srow client_service ) |
| | 69 | RETURNS bool LANGUAGE PLPGSQL AS $BODY$ |
| | 70 | BEGIN |
| | 71 | RETURN srow.start <= current_date AND ( |
| | 72 | srow.end IS NULL OR srow.end >= current_date ) AND |
| | 73 | srow."_superceededBy_id" IS NULL; |
| | 74 | END; |
| | 75 | $BODY$; |
| | 76 | <BLANKLINE> |
| | 77 | <BLANKLINE> |
| | 78 | |
| | 79 | Test '' |
| | 80 | |
| | 81 | # >>> show( "that''s it ';' ." ) |
| | 82 | that''s it ';' . |
| | 83 | >>> show( "a''''b" ) |
| | 84 | a''''b |
| | 85 | |
| | 86 | Now test percent doubling |
| | 87 | |
| | 88 | >>> show( "hello there %1 %2 %%; %" ) |
| | 89 | hello there %%1 %%2 %%; |
| | 90 | %% |
| | 91 | |
| | 92 | Test w/o dollar quote: |
| | 93 | |
| | 94 | >>> show( "$$ d;d $$", dollar_quotes = False ) |
| | 95 | $$ d; |
| | 96 | d $$ |
| | 97 | |
| | 98 | Test comments: |
| | 99 | |
| | 100 | >>> show( "this is a line; -- this; doesn't; break\n'now; quote was in comment" ) |
| | 101 | this is a line; |
| | 102 | -- this; doesn't; break |
| | 103 | 'now; quote was in comment |
| | 104 | |
| | 105 | >>> show( "/* ; a\n -- ; */;z b\n;c" ) |
| | 106 | /* ; a |
| | 107 | -- ; */; |
| | 108 | z b |
| | 109 | ; |
| | 110 | c |
| | 111 | |
| | 112 | """ |
| | 113 | outer_quote = None |
| | 114 | is_comment = False |
| | 115 | is_c_comment = False |
| | 116 | if dollar_quotes: |
| | 117 | re = _id_re |
| | 118 | else: |
| | 119 | re = _single_id_re |
| | 120 | |
| | 121 | lastPos = 0 |
| | 122 | for match in re.finditer( script ): |
| | 123 | if match.group( 'semi' ): |
| | 124 | if not ( outer_quote or is_comment or is_c_comment ): |
| | 125 | newPos = match.end( 1 ) |
| | 126 | |
| | 127 | statement = script[ lastPos : newPos ] |
| | 128 | yield _percent_re.sub( '%%', statement ) |
| | 129 | lastPos = newPos |
| | 130 | elif match.group( 'comment' ) and not is_c_comment: |
| | 131 | if not outer_quote: |
| | 132 | is_comment = True |
| | 133 | elif match.group( 'ccomment' ) and not is_comment: |
| | 134 | if not outer_quote: |
| | 135 | is_c_comment = True |
| | 136 | elif match.group( 'lineend' ): |
| | 137 | is_comment = False |
| | 138 | elif match.group( 'endccomment' ): |
| | 139 | is_c_comment = False |
| | 140 | elif not ( is_comment or is_c_comment ): |
| | 141 | quote = filter( lambda g: g is not None, match.groups() )[ 0 ] |
| | 142 | if quote == "''": |
| | 143 | # double-quote is escape for quote |
| | 144 | continue |
| | 145 | elif outer_quote and quote == outer_quote: |
| | 146 | # strings embedded in other strings needn't be |
| | 147 | # well-formed -- throw away nesting if outer quote |
| | 148 | # is found |
| | 149 | outer_quote = None |
| | 150 | elif not outer_quote: |
| | 151 | outer_quote = quote |
| | 152 | |
| | 153 | |
| | 154 | if lastPos < len( script ): |
| | 155 | yield _percent_re.sub( '%%', script[ lastPos : ] ) |
| | 156 | |
| | 157 | |
| | 158 | |
| | 159 | |
| | 160 | |
| | 161 | def _test(): |
| | 162 | import doctest |
| | 163 | doctest.testmod() |
| | 164 | |
| | 165 | if __name__ == "__main__": |
| | 166 | _test() |