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
|
"""
Neo4j DB object
"""
from enum import Enum
from neo4j_cypher_parser import Cypher_Parser, e_clause__where, e_keyword, \
e_value, e_label_set, p_node, e_ident, p_rel, p_path
import re
import logging
import neo4j_cypher_parser
from neo4j_util import rzdoc__ns_label, rzdoc__meta_ns_label
import neo4j_schema
log = logging.getLogger('rhizi')
class Query_Struct_Type(Enum):
unkown = 1
r = 2
w = 3
rw = 4
def __add__(self, other):
if self == other or self == Query_Struct_Type.rw:
return self
if self == Query_Struct_Type.unkown:
return other
if self == Query_Struct_Type.r and other != Query_Struct_Type.r:
return Query_Struct_Type.rw
if self == Query_Struct_Type.w and other != Query_Struct_Type.w:
return Query_Struct_Type.rw
def __str__(self):
if self == Query_Struct_Type.unkown: return 'unkown'
if self == Query_Struct_Type.r: return 'r'
if self == Query_Struct_Type.w: return 'w'
if self == Query_Struct_Type.rw: return 'rw'
assert False
def __eq__(self, other): # allow comparing against r/w/rw strings
if other in ['r', 'w', 'rw']:
if self == Query_Struct_Type.r and other == 'r': return True
if self == Query_Struct_Type.w and other == 'w': return True
if self == Query_Struct_Type.rw and other == 'rw': return True
if not isinstance(other, Query_Struct_Type): return False
return super(Query_Struct_Type, self).__eq__(other)
class Query_Transformation(object):
"""
A query transformation, which may be applied to either a DB_op or a DB_Query
"""
def __call__(self, value):
q_set = []
if isinstance(value, DB_Query):
q_set.append(value)
else: # assume iterable
assert hasattr(value, '__iter__')
for dbq in value:
assert isinstance(dbq, DB_Query)
q_set.append(dbq)
for dbq in q_set:
log.debug('%r' % (dbq))
self.apply_to_single_query(dbq)
log.debug('%r' % (dbq))
return value
def apply_to_single_query(self, dbq):
pass
class QT_RZDOC_NS_Filter__common(Query_Transformation):
"""
Add RZDoc name-space filter:
- inject NS labels into node patterns
- [!] ignore nodes which are part of path patterns to avoid overriding bound references
"""
def __init__(self, ns_label):
self.ns_label = ns_label
def apply_to_single_query(self, dbq):
rgx__doc_label = re.compile(r'%s[\w\d_]+' % (neo4j_schema.META_LABEL__RZDOC_NS_PREFIX))
assert None == rgx__doc_label.match(self.ns_label), 'Illegal doc ID label: %s' % (self.ns_label) # validate doc label
q_type = dbq.query_struct_type
clause_set = []
if Query_Struct_Type.w == q_type:
clause_set += dbq.pt_root.clause_set_by_kw('create')
if Query_Struct_Type.r == q_type:
clause_set += dbq.pt_root.clause_set_by_kw('match')
if Query_Struct_Type.rw == q_type:
clause_set += dbq.pt_root.clause_set_by_kw('create')
clause_set += dbq.pt_root.clause_set_by_kw('match')
for c in clause_set:
n_exp_set = c.sub_exp_set_by_type(p_node , recurse=True)
for n_exp in n_exp_set:
if n_exp.parent.__class__ == p_path:
continue;
lbl_set = n_exp.label_set
if not lbl_set: # add label set if necessary
lbl_set = n_exp.spawn_label_set()
lbl_set.add_label(self.ns_label)
# log.debug('db_q trans: in clause: %s, out clause: %s' % (cur_clause, new_clause))
class QT_RZDOC_NS_Filter(QT_RZDOC_NS_Filter__common):
def __init__(self, rzdoc):
ns_label = rzdoc__ns_label(rzdoc)
super(QT_RZDOC_NS_Filter, self).__init__(ns_label)
class QT_RZDOC_Meta_NS_Filter(QT_RZDOC_NS_Filter__common):
def __init__(self, rzdoc):
ns_label = rzdoc__meta_ns_label(rzdoc)
super(QT_RZDOC_Meta_NS_Filter, self).__init__(ns_label)
class QT_Node_Filter__meta_label_set(Query_Transformation):
# TODO: impl
# 'where 0 = length(filter(_lbl in labels(n) where _lbl =~ \'^__.*$\'))', # filter nodes with meta labels
pass
class DB_Query(object):
def __init__(self, q_arr, param_set={}):
"""
@param q_str_or_array: cypher query to add - if passed as an array ' '.join(q_str_or_array)
is used to convert it to string type
"""
assert type(q_arr) is list
# establish query type
self.q_str = ' '.join(q_arr) # FIXME: rm
self.pt_root = Cypher_Parser().parse_expression(self.q_str)
self.param_set = param_set
def __str__(self):
return self.pt_root.str__cypher_query()
def __repr__(self):
return 'q: %s, params: %s\n%s' % (self.pt_root.str__cypher_query(),
self.param_set,
self.pt_root.str__struct_tree())
def __iter__(self):
for keyword, clause_set in self.pt_root.index__kw_to_clause_set().items():
yield keyword, clause_set
def t__add_node_filter__meta_label(self):
if Query_Struct_Type.w == self.query_struct_type:
return
meta_label_cond = '0 = length(filter(_lbl in labels(n) where _lbl in {meta_label_set}))' # filter nodes with meta labels
c_set__where = self.pt_root.clause_set_by_kw('where')
if not c_set__where:
c_set__match = self.pt_root.clause_set_by_kw('match')
first_match_clause = c_set__match.pop()
wc = first_match_clause.spawn_sibling__adjacent(e_clause__where)
wc.spawn_child(e_keyword, 'where')
wc.spawn_child(e_value).value = meta_label_cond
else: # where clause present
assert len(c_set__where) == 1, 't__add_node_filter__meta_label: no support for multi-where clauses query transformation'
wc = c_set__where[0]
wc_cond = wc.condition_value
wc.set_condition(meta_label_cond + ' and ' + wc_cond)
self.param_set['meta_label_set'] = neo4j_schema.meta_label_set
@property
def query_struct_type(self):
"""
calc query_structure_type: read|write|read-write
"""
r = False
w = False
for kw, _clause_set in self.pt_root.index__kw_to_clause_set().items():
if kw in neo4j_cypher_parser.tok_set__kw__write:
w = True
if kw == 'match':
r = True
if r and w: return Query_Struct_Type.rw
if r and not w: return Query_Struct_Type.r
if w and not r: return Query_Struct_Type.w
return Query_Struct_Type.unkown
def str__cypher_query(self):
return self.pt_root.str__cypher_query()
class DB_row(object):
def __init__(self, data):
self.data = data
def __iter__(self):
for column_val in self.data:
yield column_val
def items(self):
return [x for x in self]
def __str__(self):
return str(self.items())
def __repr__(self):
return repr(self.items())
class DB_result_set(object):
def __init__(self, data):
self.data = data
def __iter__(self):
for db_row_dict in self.data['data']:
# example: dict: {u'row': [{u'title': u'foo'}]}
assert None != db_row_dict['row']
yield DB_row(db_row_dict['row'])
def items(self):
return [x for x in self]
|
