|
1
|
|
|
# Copyright (c) 2016 Fabian Kochem |
|
2
|
|
|
|
|
3
|
|
|
|
|
4
|
|
|
from libtree import exceptions |
|
5
|
|
|
from libtree.core.node_data import NodeData |
|
6
|
|
|
from libtree.utils import vectorize_nodes |
|
7
|
|
|
|
|
8
|
|
|
|
|
9
|
|
|
def get_tree_size(cur): |
|
10
|
|
|
""" |
|
11
|
|
|
Return the total amount of tree nodes. |
|
12
|
|
|
""" |
|
13
|
|
|
sql = """ |
|
14
|
|
|
SELECT |
|
15
|
|
|
COUNT(*) |
|
16
|
|
|
FROM |
|
17
|
|
|
nodes; |
|
18
|
|
|
""" |
|
19
|
|
|
cur.execute(sql) |
|
20
|
|
|
result = cur.fetchone() |
|
21
|
|
|
return result['count'] |
|
22
|
|
|
|
|
23
|
|
|
|
|
24
|
|
|
def get_root_node(cur): |
|
25
|
|
|
""" |
|
26
|
|
|
Return root node. Raise ``ValueError`` if root node doesn't exist. |
|
27
|
|
|
""" |
|
28
|
|
|
sql = """ |
|
29
|
|
|
SELECT |
|
30
|
|
|
* |
|
31
|
|
|
FROM |
|
32
|
|
|
nodes |
|
33
|
|
|
WHERE |
|
34
|
|
|
parent IS NULL; |
|
35
|
|
|
""" |
|
36
|
|
|
cur.execute(sql) |
|
37
|
|
|
result = cur.fetchone() |
|
38
|
|
|
|
|
39
|
|
|
if result is None: |
|
40
|
|
|
raise exceptions.NoRootNode() |
|
41
|
|
|
else: |
|
42
|
|
|
return NodeData(**result) |
|
43
|
|
|
|
|
44
|
|
|
|
|
45
|
|
|
def get_node(cur, id): |
|
46
|
|
|
""" |
|
47
|
|
|
Return ``NodeData`` object for given ``id``. Raises ``ValueError`` |
|
48
|
|
|
if ID doesn't exist. |
|
49
|
|
|
|
|
50
|
|
|
:param uuid4 id: Database ID |
|
51
|
|
|
""" |
|
52
|
|
|
sql = """ |
|
53
|
|
|
SELECT |
|
54
|
|
|
* |
|
55
|
|
|
FROM |
|
56
|
|
|
nodes |
|
57
|
|
|
WHERE |
|
58
|
|
|
id = %s; |
|
59
|
|
|
""" |
|
60
|
|
|
if not isinstance(id, str): |
|
61
|
|
|
raise TypeError('ID must be type string (UUID4).') |
|
62
|
|
|
|
|
63
|
|
|
cur.execute(sql, (id, )) |
|
64
|
|
|
result = cur.fetchone() |
|
65
|
|
|
|
|
66
|
|
|
if result is None: |
|
67
|
|
|
raise exceptions.NodeNotFound(id) |
|
68
|
|
|
else: |
|
69
|
|
|
return NodeData(**result) |
|
70
|
|
|
|
|
71
|
|
|
|
|
72
|
|
|
def get_node_at_position(cur, node, position): |
|
73
|
|
|
""" |
|
74
|
|
|
Return node at ``position`` in the children of ``node``. |
|
75
|
|
|
|
|
76
|
|
|
:param node: |
|
77
|
|
|
:type node: Node or uuid4 |
|
78
|
|
|
:param int position: |
|
79
|
|
|
""" |
|
80
|
|
|
sql = """ |
|
81
|
|
|
SELECT |
|
82
|
|
|
* |
|
83
|
|
|
FROM |
|
84
|
|
|
nodes |
|
85
|
|
|
WHERE |
|
86
|
|
|
parent=%s |
|
87
|
|
|
AND |
|
88
|
|
|
position=%s |
|
89
|
|
|
""" |
|
90
|
|
|
|
|
91
|
|
|
cur.execute(sql, (str(node), position)) |
|
92
|
|
|
result = cur.fetchone() |
|
93
|
|
|
|
|
94
|
|
|
if result is None: |
|
95
|
|
|
raise ValueError('Node does not exist.') |
|
96
|
|
|
else: |
|
97
|
|
|
return NodeData(**result) |
|
98
|
|
|
|
|
99
|
|
|
|
|
100
|
|
|
def get_children(cur, node): |
|
101
|
|
|
""" |
|
102
|
|
|
Return an iterator that yields a ``NodeData`` object of every |
|
103
|
|
|
immediate child. |
|
104
|
|
|
|
|
105
|
|
|
:param node: |
|
106
|
|
|
:type node: Node or uuid4 |
|
107
|
|
|
""" |
|
108
|
|
|
sql = """ |
|
109
|
|
|
SELECT |
|
110
|
|
|
* |
|
111
|
|
|
FROM |
|
112
|
|
|
nodes |
|
113
|
|
|
WHERE |
|
114
|
|
|
parent=%s |
|
115
|
|
|
ORDER BY |
|
116
|
|
|
position; |
|
117
|
|
|
""" |
|
118
|
|
|
cur.execute(sql, (str(node), )) |
|
119
|
|
|
for result in cur: |
|
120
|
|
|
yield NodeData(**result) |
|
121
|
|
|
|
|
122
|
|
|
|
|
123
|
|
|
def get_child_ids(cur, node): |
|
124
|
|
|
""" |
|
125
|
|
|
Return an iterator that yields the ID of every immediate child. |
|
126
|
|
|
|
|
127
|
|
|
:param node: |
|
128
|
|
|
:type node: Node or uuid4 |
|
129
|
|
|
""" |
|
130
|
|
|
sql = """ |
|
131
|
|
|
SELECT |
|
132
|
|
|
id |
|
133
|
|
|
FROM |
|
134
|
|
|
nodes |
|
135
|
|
|
WHERE |
|
136
|
|
|
parent=%s |
|
137
|
|
|
ORDER BY |
|
138
|
|
|
position; |
|
139
|
|
|
""" |
|
140
|
|
|
cur.execute(sql, (str(node), )) |
|
141
|
|
|
for result in cur: |
|
142
|
|
|
yield str(result['id']) |
|
143
|
|
|
|
|
144
|
|
|
|
|
145
|
|
|
def get_children_count(cur, node): |
|
146
|
|
|
""" |
|
147
|
|
|
Get amount of immediate children. |
|
148
|
|
|
|
|
149
|
|
|
:param node: Node |
|
150
|
|
|
:type node: Node or uuid4 |
|
151
|
|
|
""" |
|
152
|
|
|
sql = """ |
|
153
|
|
|
SELECT |
|
154
|
|
|
COUNT(*) |
|
155
|
|
|
FROM |
|
156
|
|
|
nodes |
|
157
|
|
|
WHERE |
|
158
|
|
|
parent=%s; |
|
159
|
|
|
""" |
|
160
|
|
|
cur.execute(sql, (str(node), )) |
|
161
|
|
|
result = cur.fetchone() |
|
162
|
|
|
return result['count'] |
|
163
|
|
|
|
|
164
|
|
|
|
|
165
|
|
|
def get_ancestors(cur, node, sort=True): |
|
166
|
|
|
""" |
|
167
|
|
|
Return an iterator which yields a ``NodeData`` object for every |
|
168
|
|
|
node in the hierarchy chain from ``node`` to root node. |
|
169
|
|
|
|
|
170
|
|
|
:param node: |
|
171
|
|
|
:type node: Node or uuid4 |
|
172
|
|
|
:param bool sort: Start with closest node and end with root node. |
|
173
|
|
|
(default: True). Set to False if order is |
|
174
|
|
|
unimportant. |
|
175
|
|
|
""" |
|
176
|
|
|
# TODO: benchmark if vectorize_nodes() or WITH RECURSIVE is faster |
|
177
|
|
|
sql = """ |
|
178
|
|
|
SELECT |
|
179
|
|
|
nodes.* |
|
180
|
|
|
FROM |
|
181
|
|
|
ancestors |
|
182
|
|
|
INNER JOIN |
|
183
|
|
|
nodes |
|
184
|
|
|
ON |
|
185
|
|
|
ancestors.ancestor=nodes.id |
|
186
|
|
|
WHERE |
|
187
|
|
|
ancestors.node=%s; |
|
188
|
|
|
""" |
|
189
|
|
|
cur.execute(sql, (str(node), )) |
|
190
|
|
|
|
|
191
|
|
|
if sort: |
|
192
|
|
|
make_node = lambda r: NodeData(**r) |
|
193
|
|
|
for node in vectorize_nodes(map(make_node, cur))[::-1]: |
|
194
|
|
|
yield node |
|
195
|
|
|
else: |
|
196
|
|
|
for result in cur: |
|
197
|
|
|
yield NodeData(**result) |
|
198
|
|
|
|
|
199
|
|
|
|
|
200
|
|
|
def get_ancestor_ids(cur, node): |
|
201
|
|
|
""" |
|
202
|
|
|
Return an iterator that yields the ID of every element while |
|
203
|
|
|
traversing from ``node`` to the root node. |
|
204
|
|
|
|
|
205
|
|
|
:param node: |
|
206
|
|
|
:type node: Node or uuid4 |
|
207
|
|
|
""" |
|
208
|
|
|
# TODO: add sort parameter |
|
209
|
|
|
sql = """ |
|
210
|
|
|
SELECT |
|
211
|
|
|
ancestor |
|
212
|
|
|
FROM |
|
213
|
|
|
ancestors |
|
214
|
|
|
WHERE |
|
215
|
|
|
node=%s; |
|
216
|
|
|
""" |
|
217
|
|
|
cur.execute(sql, (str(node), )) |
|
218
|
|
|
for result in cur: |
|
219
|
|
|
yield str(result['ancestor']) |
|
220
|
|
|
|
|
221
|
|
|
|
|
222
|
|
|
def get_descendants(cur, node): |
|
223
|
|
|
""" |
|
224
|
|
|
Return an iterator that yields the ID of every element while |
|
225
|
|
|
traversing from ``node`` to the root node. |
|
226
|
|
|
|
|
227
|
|
|
:param node: |
|
228
|
|
|
:type node: Node or uuid4 |
|
229
|
|
|
""" |
|
230
|
|
|
sql = """ |
|
231
|
|
|
SELECT |
|
232
|
|
|
nodes.* |
|
233
|
|
|
FROM |
|
234
|
|
|
ancestors |
|
235
|
|
|
INNER JOIN |
|
236
|
|
|
nodes |
|
237
|
|
|
ON |
|
238
|
|
|
ancestors.node=nodes.id |
|
239
|
|
|
WHERE |
|
240
|
|
|
ancestors.ancestor=%s; |
|
241
|
|
|
""" |
|
242
|
|
|
cur.execute(sql, (str(node), )) |
|
243
|
|
|
for result in cur: |
|
244
|
|
|
yield NodeData(**result) |
|
245
|
|
|
|
|
246
|
|
|
|
|
247
|
|
|
def get_descendant_ids(cur, node): |
|
248
|
|
|
""" |
|
249
|
|
|
Return an iterator that yields a ``NodeData`` object of each element |
|
250
|
|
|
in the nodes subtree. Be careful when converting this iterator to an |
|
251
|
|
|
iterable (like list or set) because it could contain billions of |
|
252
|
|
|
objects. |
|
253
|
|
|
|
|
254
|
|
|
:param node: |
|
255
|
|
|
:type node: Node or uuid4 |
|
256
|
|
|
""" |
|
257
|
|
|
sql = """ |
|
258
|
|
|
SELECT |
|
259
|
|
|
node |
|
260
|
|
|
FROM |
|
261
|
|
|
ancestors |
|
262
|
|
|
WHERE |
|
263
|
|
|
ancestor=%s; |
|
264
|
|
|
""" |
|
265
|
|
|
cur.execute(sql, (str(node), )) |
|
266
|
|
|
for result in cur: |
|
267
|
|
|
yield str(result['node']) |
|
268
|
|
|
|