1 # -*- coding: utf-8 -*-
3 # Copyright 2018 Telefonica S.A.
5 # Licensed under the Apache License, Version 2.0 (the "License");
6 # you may not use this file except in compliance with the License.
7 # You may obtain a copy of the License at
9 # http://www.apache.org/licenses/LICENSE-2.0
11 # Unless required by applicable law or agreed to in writing, software
12 # distributed under the License is distributed on an "AS IS" BASIS,
13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
15 # See the License for the specific language governing permissions and
16 # limitations under the License.
20 from http
import HTTPStatus
21 from copy
import deepcopy
22 from Crypto
.Cipher
import AES
23 from base64
import b64decode
, b64encode
24 from osm_common
.common_utils
import FakeLock
25 from threading
import Lock
27 __author__
= "Alfonso Tierno <alfonso.tiernosepulveda@telefonica.com>"
30 class DbException(Exception):
32 def __init__(self
, message
, http_code
=HTTPStatus
.NOT_FOUND
):
33 self
.http_code
= http_code
34 Exception.__init
__(self
, "database exception " + str(message
))
39 def __init__(self
, logger_name
='db', lock
=False):
42 :param logger_name: logging name
43 :param lock: Used to protect simultaneous access to the same instance class by several threads:
44 False, None: Do not protect, this object will only be accessed by one thread
45 True: This object needs to be protected by several threads accessing.
46 Lock object. Use thi Lock for the threads access protection
48 self
.logger
= logging
.getLogger(logger_name
)
49 self
.master_password
= None
50 self
.secret_key
= None
52 self
.lock
= FakeLock()
55 elif isinstance(lock
, Lock
):
58 raise ValueError("lock parameter must be a Lock classclass or boolean")
60 def db_connect(self
, config
, target_version
=None):
63 :param config: Configuration of database. Contains among others:
64 host: database hosst (mandatory)
65 port: database port (mandatory)
66 name: database name (mandatory)
67 user: database username
68 password: database password
69 masterpassword: database password used for sensible information encryption
70 :param target_version: if provided it checks if database contains required version, raising exception otherwise.
71 :return: None or raises DbException on error
73 raise DbException("Method 'db_connect' not implemented")
75 def db_disconnect(self
):
77 Disconnect from database
82 def get_list(self
, table
, q_filter
=None):
84 Obtain a list of entries matching q_filter
85 :param table: collection or table
86 :param q_filter: Filter
87 :return: a list (can be empty) with the found entries. Raises DbException on error
89 raise DbException("Method 'get_list' not implemented")
91 def get_one(self
, table
, q_filter
=None, fail_on_empty
=True, fail_on_more
=True):
93 Obtain one entry matching q_filter
94 :param table: collection or table
95 :param q_filter: Filter
96 :param fail_on_empty: If nothing matches filter it returns None unless this flag is set tu True, in which case
97 it raises a DbException
98 :param fail_on_more: If more than one matches filter it returns one of then unless this flag is set tu True, so
99 that it raises a DbException
100 :return: The requested element, or None
102 raise DbException("Method 'get_one' not implemented")
104 def del_list(self
, table
, q_filter
=None):
106 Deletes all entries that match q_filter
107 :param table: collection or table
108 :param q_filter: Filter
109 :return: Dict with the number of entries deleted
111 raise DbException("Method 'del_list' not implemented")
113 def del_one(self
, table
, q_filter
=None, fail_on_empty
=True):
115 Deletes one entry that matches q_filter
116 :param table: collection or table
117 :param q_filter: Filter
118 :param fail_on_empty: If nothing matches filter it returns '0' deleted unless this flag is set tu True, in
119 which case it raises a DbException
120 :return: Dict with the number of entries deleted
122 raise DbException("Method 'del_one' not implemented")
124 def create(self
, table
, indata
):
126 Add a new entry at database
127 :param table: collection or table
128 :param indata: content to be added
129 :return: database id of the inserted element. Raises a DbException on error
131 raise DbException("Method 'create' not implemented")
133 def set_one(self
, table
, q_filter
, update_dict
, fail_on_empty
=True):
135 Modifies an entry at database
136 :param table: collection or table
137 :param q_filter: Filter
138 :param update_dict: Plain dictionary with the content to be updated. It is a dot separated keys and a value
139 :param fail_on_empty: If nothing matches filter it returns None unless this flag is set tu True, in which case
140 it raises a DbException
141 :return: Dict with the number of entries modified. None if no matching is found.
143 raise DbException("Method 'set_one' not implemented")
145 def set_list(self
, table
, q_filter
, update_dict
):
147 Modifies al matching entries at database
148 :param table: collection or table
149 :param q_filter: Filter
150 :param update_dict: Plain dictionary with the content to be updated. It is a dot separated keys and a value
151 :return: Dict with the number of entries modified
153 raise DbException("Method 'set_list' not implemented")
155 def replace(self
, table
, _id
, indata
, fail_on_empty
=True):
157 Replace the content of an entry
158 :param table: collection or table
159 :param _id: internal database id
160 :param indata: content to replace
161 :param fail_on_empty: If nothing matches filter it returns None unless this flag is set tu True, in which case
162 it raises a DbException
163 :return: Dict with the number of entries replaced
165 raise DbException("Method 'replace' not implemented")
168 def _join_passwords(passwd_byte
, passwd_str
):
170 Modifies passwd_byte with the xor of passwd_str. Used for adding salt, join passwords, etc
171 :param passwd_byte: original password in bytes, 32 byte length
172 :param passwd_str: string salt to be added
173 :return: modified password in bytes
177 secret_key
= bytearray(passwd_byte
)
178 for i
, b
in enumerate(passwd_str
.encode()):
179 secret_key
[i
% 32] ^
= b
180 return bytes(secret_key
)
182 def set_secret_key(self
, secret_key
):
184 Set internal secret key used for encryption
185 :param secret_key: byte array length 32 with the secret_key
188 assert (len(secret_key
) == 32)
189 self
.secret_key
= self
._join
_passwords
(secret_key
, self
.master_password
)
191 def encrypt(self
, value
, schema_version
=None, salt
=None):
194 :param value: value to be encrypted. It is string/unicode
195 :param schema_version: used for version control. If None or '1.0' no encryption is done.
196 If '1.1' symmetric AES encryption is done
197 :param salt: optional salt to be used. Must be str
198 :return: Encrypted content of value
200 if not schema_version
or schema_version
== '1.0':
203 if not self
.secret_key
:
204 raise DbException("Cannot encrypt. Missing secret_key", http_code
=HTTPStatus
.INTERNAL_SERVER_ERROR
)
205 secret_key
= self
._join
_passwords
(self
.secret_key
, salt
)
206 cipher
= AES
.new(secret_key
)
207 padded_private_msg
= value
+ ('\0' * ((16-len(value
)) % 16))
208 encrypted_msg
= cipher
.encrypt(padded_private_msg
)
209 encoded_encrypted_msg
= b64encode(encrypted_msg
)
210 return encoded_encrypted_msg
.decode("ascii")
212 def decrypt(self
, value
, schema_version
=None, salt
=None):
214 Decrypt an encrypted value
215 :param value: value to be decrypted. It is a base64 string
216 :param schema_version: used for known encryption method used. If None or '1.0' no encryption has been done.
217 If '1.1' symmetric AES encryption has been done
218 :param salt: optional salt to be used
219 :return: Plain content of value
221 if not schema_version
or schema_version
== '1.0':
224 if not self
.secret_key
:
225 raise DbException("Cannot decrypt. Missing secret_key", http_code
=HTTPStatus
.INTERNAL_SERVER_ERROR
)
226 secret_key
= self
._join
_passwords
(self
.secret_key
, salt
)
227 encrypted_msg
= b64decode(value
)
228 cipher
= AES
.new(secret_key
)
229 decrypted_msg
= cipher
.decrypt(encrypted_msg
)
230 unpadded_private_msg
= decrypted_msg
.decode().rstrip('\0')
231 return unpadded_private_msg
234 def deep_update_rfc7396(dict_to_change
, dict_reference
, key_list
=None):
236 Modifies one dictionary with the information of the other following https://tools.ietf.org/html/rfc7396
237 Basically is a recursive python 'dict_to_change.update(dict_reference)', but a value of None is used to delete.
238 It implements an extra feature that allows modifying an array. RFC7396 only allows replacing the entire array.
239 For that, dict_reference should contains a dict with keys starting by "$" with the following meaning:
240 $[index] <index> is an integer for targeting a concrete index from dict_to_change array. If the value is None
241 the element of the array is deleted, otherwise it is edited.
242 $+[index] The value is inserted at this <index>. A value of None has not sense and an exception is raised.
243 $+ The value is appended at the end. A value of None has not sense and an exception is raised.
244 $val It looks for all the items in the array dict_to_change equal to <val>. <val> is evaluated as yaml,
245 that is, numbers are taken as type int, true/false as boolean, etc. Use quotes to force string.
246 Nothing happens if no match is found. If the value is None the matched elements are deleted.
247 $key: val In case a dictionary is passed in yaml format, if looks for all items in the array dict_to_change
248 that are dictionaries and contains this <key> equal to <val>. Several keys can be used by yaml
249 format '{key: val, key: val, ...}'; and all of them mast match. Nothing happens if no match is
250 found. If value is None the matched items are deleted, otherwise they are edited.
251 $+val If no match if found (see '$val'), the value is appended to the array. If any match is found nothing
252 is changed. A value of None has not sense.
253 $+key: val If no match if found (see '$key: val'), the value is appended to the array. If any match is found
254 nothing is changed. A value of None has not sense.
255 If there are several editions, insertions and deletions; editions and deletions are done first in reverse index
256 order; then insertions also in reverse index order; and finally appends in any order. So indexes used at
257 insertions must take into account the deleted items.
258 :param dict_to_change: Target dictionary to be changed.
259 :param dict_reference: Dictionary that contains changes to be applied.
260 :param key_list: This is used internally for recursive calls. Do not fill this parameter.
261 :return: none or raises and exception only at array modification when there is a bad format or conflict.
263 def _deep_update_array(array_to_change
, _dict_reference
, _key_list
):
265 to_insert_at_index
= {}
266 values_to_edit_delete
= {}
267 indexes_to_edit_delete
= []
270 for k
in _dict_reference
:
271 _key_list
[-1] = str(k
)
272 if not isinstance(k
, str) or not k
.startswith("$"):
273 if array_edition
is True:
274 raise DbException("Found array edition (keys starting with '$') and pure dictionary edition in the"
275 " same dict at '{}'".format(":".join(_key_list
[:-1])))
276 array_edition
= False
279 if array_edition
is False:
280 raise DbException("Found array edition (keys starting with '$') and pure dictionary edition in the"
281 " same dict at '{}'".format(":".join(_key_list
[:-1])))
284 indexes
= [] # indexes to edit or insert
286 if kitem
.startswith('+'):
289 if _dict_reference
[k
] is None:
290 raise DbException("A value of None has not sense for insertions at '{}'".format(
291 ":".join(_key_list
)))
293 if kitem
.startswith('[') and kitem
.endswith(']'):
295 index
= int(kitem
[1:-1])
297 index
+= len(array_to_change
)
299 index
= 0 # skip outside index edition
300 indexes
.append(index
)
302 raise DbException("Wrong format at '{}'. Expecting integer index inside quotes".format(
303 ":".join(_key_list
)))
305 # match_found_skip = False
307 filter_in
= yaml
.safe_load(kitem
)
309 raise DbException("Wrong format at '{}'. Expecting '$<yaml-format>'".format(":".join(_key_list
)))
310 if isinstance(filter_in
, dict):
311 for index
, item
in enumerate(array_to_change
):
312 for filter_k
, filter_v
in filter_in
.items():
313 if not isinstance(item
, dict) or filter_k
not in item
or item
[filter_k
] != filter_v
:
317 # match_found_skip = True
321 indexes
.append(index
)
325 while True: # if not match a ValueError exception will be raise
326 index
= array_to_change
.index(filter_in
, index
)
328 # match_found_skip = True
331 indexes
.append(index
)
336 # if match_found_skip:
339 raise DbException("Wrong format at '{}'. Expecting '$+', '$[<index]' or '$[<filter>]'".format(
340 ":".join(_key_list
)))
341 for index
in indexes
:
343 if index
in to_insert_at_index
and to_insert_at_index
[index
] != _dict_reference
[k
]:
344 # Several different insertions on the same item of the array
345 raise DbException("Conflict at '{}'. Several insertions on same array index {}".format(
346 ":".join(_key_list
), index
))
347 to_insert_at_index
[index
] = _dict_reference
[k
]
349 if index
in indexes_to_edit_delete
and values_to_edit_delete
[index
] != _dict_reference
[k
]:
350 # Several different editions on the same item of the array
351 raise DbException("Conflict at '{}'. Several editions on array index {}".format(
352 ":".join(_key_list
), index
))
353 indexes_to_edit_delete
.append(index
)
354 values_to_edit_delete
[index
] = _dict_reference
[k
]
357 to_append
[k
] = _dict_reference
[k
]
358 # elif _dict_reference[k] is not None:
359 # raise DbException("Not found any match to edit in the array, or wrong format at '{}'".format(
360 # ":".join(_key_list)))
362 # edition/deletion is done before insertion
363 indexes_to_edit_delete
.sort(reverse
=True)
364 for index
in indexes_to_edit_delete
:
365 _key_list
[-1] = str(index
)
367 if values_to_edit_delete
[index
] is None: # None->Anything
369 del (array_to_change
[index
])
371 pass # it is not consider an error if this index does not exist
372 elif not isinstance(values_to_edit_delete
[index
], dict): # NotDict->Anything
373 array_to_change
[index
] = deepcopy(values_to_edit_delete
[index
])
374 elif isinstance(array_to_change
[index
], dict): # Dict->Dict
375 deep_update_rfc7396(array_to_change
[index
], values_to_edit_delete
[index
], _key_list
)
376 else: # Dict->NotDict
377 if isinstance(array_to_change
[index
], list): # Dict->List. Check extra array edition
378 if _deep_update_array(array_to_change
[index
], values_to_edit_delete
[index
], _key_list
):
380 array_to_change
[index
] = deepcopy(values_to_edit_delete
[index
])
381 # calling deep_update_rfc7396 to delete the None values
382 deep_update_rfc7396(array_to_change
[index
], values_to_edit_delete
[index
], _key_list
)
384 raise DbException("Array edition index out of range at '{}'".format(":".join(_key_list
)))
386 # insertion with indexes
387 to_insert_indexes
= list(to_insert_at_index
.keys())
388 to_insert_indexes
.sort(reverse
=True)
389 for index
in to_insert_indexes
:
390 array_to_change
.insert(index
, to_insert_at_index
[index
])
393 for k
, insert_value
in to_append
.items():
394 _key_list
[-1] = str(k
)
395 insert_value_copy
= deepcopy(insert_value
)
396 if isinstance(insert_value_copy
, dict):
397 # calling deep_update_rfc7396 to delete the None values
398 deep_update_rfc7396(insert_value_copy
, insert_value
, _key_list
)
399 array_to_change
.append(insert_value_copy
)
409 for k
in dict_reference
:
410 key_list
[-1] = str(k
)
411 if dict_reference
[k
] is None: # None->Anything
412 if k
in dict_to_change
:
413 del dict_to_change
[k
]
414 elif not isinstance(dict_reference
[k
], dict): # NotDict->Anything
415 dict_to_change
[k
] = deepcopy(dict_reference
[k
])
416 elif k
not in dict_to_change
: # Dict->Empty
417 dict_to_change
[k
] = deepcopy(dict_reference
[k
])
418 # calling deep_update_rfc7396 to delete the None values
419 deep_update_rfc7396(dict_to_change
[k
], dict_reference
[k
], key_list
)
420 elif isinstance(dict_to_change
[k
], dict): # Dict->Dict
421 deep_update_rfc7396(dict_to_change
[k
], dict_reference
[k
], key_list
)
422 else: # Dict->NotDict
423 if isinstance(dict_to_change
[k
], list): # Dict->List. Check extra array edition
424 if _deep_update_array(dict_to_change
[k
], dict_reference
[k
], key_list
):
426 dict_to_change
[k
] = deepcopy(dict_reference
[k
])
427 # calling deep_update_rfc7396 to delete the None values
428 deep_update_rfc7396(dict_to_change
[k
], dict_reference
[k
], key_list
)
432 def deep_update(dict_to_change
, dict_reference
):
433 """ Maintained for backward compatibility. Use deep_update_rfc7396 instead"""
434 return deep_update_rfc7396(dict_to_change
, dict_reference
)