-
Notifications
You must be signed in to change notification settings - Fork 403
/
ssm.py
1192 lines (1005 loc) · 41.9 KB
/
ssm.py
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
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
"""
AWS SSM Parameter retrieval and caching utility
"""
from __future__ import annotations
import logging
import os
import warnings
from typing import TYPE_CHECKING, Any, Literal, overload
import boto3
from aws_lambda_powertools.shared import constants
from aws_lambda_powertools.shared.functions import (
resolve_max_age,
resolve_truthy_env_var_choice,
slice_dictionary,
)
from aws_lambda_powertools.utilities.parameters.base import (
BaseProvider,
transform_value,
)
from aws_lambda_powertools.utilities.parameters.constants import (
DEFAULT_MAX_AGE_SECS,
DEFAULT_PROVIDERS,
SSM_PARAMETER_TIER,
SSM_PARAMETER_TYPES,
)
from aws_lambda_powertools.utilities.parameters.exceptions import GetParameterError, SetParameterError
from aws_lambda_powertools.warnings import PowertoolsDeprecationWarning
if TYPE_CHECKING:
from botocore.config import Config
from mypy_boto3_ssm.client import SSMClient
from mypy_boto3_ssm.type_defs import GetParametersResultTypeDef, PutParameterResultTypeDef
from aws_lambda_powertools.utilities.parameters.types import TransformOptions
logger = logging.getLogger(__name__)
class SSMProvider(BaseProvider):
"""
AWS Systems Manager Parameter Store Provider
Parameters
----------
config: botocore.config.Config, optional
Botocore configuration to pass during client initialization
boto3_session : boto3.session.Session, optional
Boto3 session to create a boto3_client from
boto3_client: SSMClient, optional
Boto3 SSM Client to use, boto3_session will be ignored if both are provided
Example
-------
**Retrieves a parameter value from Systems Manager Parameter Store**
>>> from aws_lambda_powertools.utilities.parameters import SSMProvider
>>> ssm_provider = SSMProvider()
>>>
>>> value = ssm_provider.get("/my/parameter")
>>>
>>> print(value)
My parameter value
**Retrieves a parameter value from Systems Manager Parameter Store in another AWS region**
>>> from botocore.config import Config
>>> from aws_lambda_powertools.utilities.parameters import SSMProvider
>>>
>>> config = Config(region_name="us-west-1")
>>> ssm_provider = SSMProvider(config=config)
>>>
>>> value = ssm_provider.get("/my/parameter")
>>>
>>> print(value)
My parameter value
**Retrieves multiple parameter values from Systems Manager Parameter Store using a path prefix**
>>> from aws_lambda_powertools.utilities.parameters import SSMProvider
>>> ssm_provider = SSMProvider()
>>>
>>> values = ssm_provider.get_multiple("/my/path/prefix")
>>>
>>> for key, value in values.items():
... print(key, value)
/my/path/prefix/a Parameter value a
/my/path/prefix/b Parameter value b
/my/path/prefix/c Parameter value c
**Retrieves multiple parameter values from Systems Manager Parameter Store passing options to the SDK call**
>>> from aws_lambda_powertools.utilities.parameters import SSMProvider
>>> ssm_provider = SSMProvider()
>>>
>>> values = ssm_provider.get_multiple("/my/path/prefix", MaxResults=10)
>>>
>>> for key, value in values.items():
... print(key, value)
/my/path/prefix/a Parameter value a
/my/path/prefix/b Parameter value b
/my/path/prefix/c Parameter value c
"""
_MAX_GET_PARAMETERS_ITEM = 10
_ERRORS_KEY = "_errors"
def __init__(
self,
config: Config | None = None,
boto_config: Config | None = None,
boto3_session: boto3.session.Session | None = None,
boto3_client: SSMClient | None = None,
):
"""
Initialize the SSM Parameter Store client
"""
if config:
warnings.warn(
message="The 'config' parameter is deprecated in V3 and will be removed in V4. "
"Please use 'boto_config' instead.",
category=PowertoolsDeprecationWarning,
stacklevel=2,
)
if boto3_client is None:
boto3_session = boto3_session or boto3.session.Session()
boto3_client = boto3_session.client("ssm", config=boto_config or config)
self.client = boto3_client
super().__init__(client=self.client)
def get_multiple( # type: ignore[override]
self,
path: str,
max_age: int | None = None,
transform: TransformOptions = None,
raise_on_transform_error: bool = False,
decrypt: bool | None = None,
force_fetch: bool = False,
recursive: bool = False,
**sdk_options,
) -> dict[str, str] | dict[str, bytes] | dict[str, dict]:
"""
Retrieve multiple parameters based on a path prefix
Parameters
----------
path: str
Parameter path used to retrieve multiple parameters
max_age: int, optional
Maximum age of the cached value
transform: str, optional
Optional transformation of the parameter value. Supported values
are "json" for JSON strings, "binary" for base 64 encoded
values or "auto" which looks at the attribute key to determine the type.
raise_on_transform_error: bool, optional
Raises an exception if any transform fails, otherwise this will
return a None value for each transform that failed
force_fetch: bool, optional
Force update even before a cached item has expired, defaults to False
recursive: bool, optional
If this should retrieve the parameter values recursively or not
sdk_options: dict, optional
Arguments that will be passed directly to the underlying API call
Raises
------
GetParameterError
When the parameter provider fails to retrieve parameter values for
a given path.
TransformParameterError
When the parameter provider fails to transform a parameter value.
"""
# If max_age is not set, resolve it from the environment variable, defaulting to DEFAULT_MAX_AGE_SECS
max_age = resolve_max_age(env=os.getenv(constants.PARAMETERS_MAX_AGE_ENV, DEFAULT_MAX_AGE_SECS), choice=max_age)
# If decrypt is not set, resolve it from the environment variable, defaulting to False
decrypt = resolve_truthy_env_var_choice(
env=os.getenv(constants.PARAMETERS_SSM_DECRYPT_ENV, "false"),
choice=decrypt,
)
sdk_options["decrypt"] = decrypt
sdk_options["recursive"] = recursive
return super().get_multiple(path, max_age, transform, raise_on_transform_error, force_fetch, **sdk_options)
# We break Liskov substitution principle due to differences in signatures of this method and superclass get method
# We ignore mypy error, as changes to the signature here or in a superclass is a breaking change to users
def get( # type: ignore[override]
self,
name: str,
max_age: int | None = None,
transform: TransformOptions = None,
decrypt: bool | None = None,
force_fetch: bool = False,
**sdk_options,
) -> str | bytes | dict | None:
"""
Retrieve a parameter value or return the cached value
Parameters
----------
name: str
Parameter name
max_age: int, optional
Maximum age of the cached value
transform: str
Optional transformation of the parameter value. Supported values
are "json" for JSON strings and "binary" for base 64 encoded
values.
decrypt: bool, optional
If the parameter value should be decrypted
force_fetch: bool, optional
Force update even before a cached item has expired, defaults to False
sdk_options: dict, optional
Arguments that will be passed directly to the underlying API call
Raises
------
GetParameterError
When the parameter provider fails to retrieve a parameter value for
a given name.
TransformParameterError
When the parameter provider fails to transform a parameter value.
"""
# If max_age is not set, resolve it from the environment variable, defaulting to DEFAULT_MAX_AGE_SECS
max_age = resolve_max_age(env=os.getenv(constants.PARAMETERS_MAX_AGE_ENV, DEFAULT_MAX_AGE_SECS), choice=max_age)
# If decrypt is not set, resolve it from the environment variable, defaulting to False
decrypt = resolve_truthy_env_var_choice(
env=os.getenv(constants.PARAMETERS_SSM_DECRYPT_ENV, "false"),
choice=decrypt,
)
# Add to `decrypt` sdk_options to we can have an explicit option for this
sdk_options["decrypt"] = decrypt
return super().get(name, max_age, transform, force_fetch, **sdk_options)
@overload
def set(
self,
name: str,
value: list[str],
*,
overwrite: bool = False,
description: str = "",
parameter_type: Literal["StringList"] = "StringList",
tier: Literal["Standard", "Advanced", "Intelligent-Tiering"] = "Standard",
kms_key_id: str | None = "None",
**sdk_options,
): ...
@overload
def set(
self,
name: str,
value: str,
*,
overwrite: bool = False,
description: str = "",
parameter_type: Literal["SecureString"] = "SecureString",
tier: Literal["Standard", "Advanced", "Intelligent-Tiering"] = "Standard",
kms_key_id: str,
**sdk_options,
): ...
@overload
def set(
self,
name: str,
value: str,
*,
overwrite: bool = False,
description: str = "",
parameter_type: Literal["String"] = "String",
tier: Literal["Standard", "Advanced", "Intelligent-Tiering"] = "Standard",
kms_key_id: str | None = None,
**sdk_options,
): ...
def set(
self,
name: str,
value: str | list[str],
*,
overwrite: bool = False,
description: str = "",
parameter_type: SSM_PARAMETER_TYPES = "String",
tier: SSM_PARAMETER_TIER = "Standard",
kms_key_id: str | None = None,
**sdk_options,
) -> PutParameterResultTypeDef:
"""
Sets a parameter in AWS Systems Manager Parameter Store.
Parameters
----------
name: str
The fully qualified name includes the complete hierarchy of the parameter name and name.
value: str
The parameter value
overwrite: bool, optional
If the parameter value should be overwritten, False by default
description: str, optional
The description of the parameter
parameter_type: str, optional
Type of the parameter. Allowed values are String, StringList, and SecureString
tier: str, optional
The parameter tier to use. Allowed values are Standard, Advanced, and Intelligent-Tiering
kms_key_id: str, optional
The KMS key id to use to encrypt the parameter
sdk_options: dict, optional
Dictionary of options that will be passed to the Parameter Store get_parameter API call
Raises
------
SetParameterError
When the parameter provider fails to retrieve a parameter value for
a given name.
URLs:
-------
https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/ssm/client/put_parameter.html
Example
-------
**Sets a parameter value from Systems Manager Parameter Store**
>>> from aws_lambda_powertools.utilities import parameters
>>>
>>> response = parameters.set_parameter(name="/my/example/parameter", value="More Powertools")
>>>
>>> print(response)
123
Returns
-------
PutParameterResultTypeDef
The dict returned by boto3.
"""
opts = {
"Name": name,
"Value": value,
"Overwrite": overwrite,
"Type": parameter_type,
"Tier": tier,
"Description": description,
**sdk_options,
}
if kms_key_id:
opts["KeyId"] = kms_key_id
try:
return self.client.put_parameter(**opts)
except Exception as exc:
raise SetParameterError(f"Error setting parameter - {str(exc)}") from exc
def _get(self, name: str, decrypt: bool = False, **sdk_options) -> str:
"""
Retrieve a parameter value from AWS Systems Manager Parameter Store
Parameters
----------
name: str
Parameter name
decrypt: bool, optional
If the parameter value should be decrypted
sdk_options: dict, optional
Dictionary of options that will be passed to the Parameter Store get_parameter API call
"""
# Explicit arguments will take precedence over keyword arguments
sdk_options["Name"] = name
sdk_options["WithDecryption"] = decrypt
return self.client.get_parameter(**sdk_options)["Parameter"]["Value"]
def _get_multiple(
self,
path: str,
decrypt: bool | None = None,
recursive: bool = False,
**sdk_options,
) -> dict[str, str]:
"""
Retrieve multiple parameter values from AWS Systems Manager Parameter Store
Parameters
----------
path: str
Path to retrieve the parameters
decrypt: bool, optional
If the parameter values should be decrypted
recursive: bool, optional
If this should retrieve the parameter values recursively or not
sdk_options: dict, optional
Dictionary of options that will be passed to the Parameter Store get_parameters_by_path API call
"""
# Explicit arguments will take precedence over keyword arguments
sdk_options["Path"] = path
sdk_options["WithDecryption"] = decrypt
sdk_options["Recursive"] = recursive
parameters = {}
for page in self.client.get_paginator("get_parameters_by_path").paginate(**sdk_options):
for parameter in page.get("Parameters", []):
# Standardize the parameter name
# The parameter name returned by SSM will contain the full path.
# However, for readability, we should return only the part after
# the path.
name = parameter["Name"]
if name.startswith(path):
name = name[len(path) :]
name = name.lstrip("/")
parameters[name] = parameter["Value"]
return parameters
# NOTE: When bandwidth permits, allocate a week to refactor to lower cognitive load
def get_parameters_by_name(
self,
parameters: dict[str, dict],
transform: TransformOptions = None,
decrypt: bool | None = None,
max_age: int | None = None,
raise_on_error: bool = True,
) -> dict[str, str] | dict[str, bytes] | dict[str, dict]:
"""
Retrieve multiple parameter values by name from SSM or cache.
Raise_on_error decides on error handling strategy:
- A) Default to fail-fast. Raises GetParameterError upon any error
- B) Gracefully aggregate all parameters that failed under "_errors" key
It transparently uses GetParameter and/or GetParameters depending on decryption requirements.
┌────────────────────────┐
┌───▶ Decrypt entire batch │─────┐
│ └────────────────────────┘ │ ┌────────────────────┐
│ ├─────▶ GetParameters API │
┌──────────────────┐ │ ┌────────────────────────┐ │ └────────────────────┘
│ Split batch │─── ┼──▶│ No decryption required │─────┘
└──────────────────┘ │ └────────────────────────┘
│ ┌────────────────────┐
│ ┌────────────────────────┐ │ GetParameter API │
└──▶│Decrypt some but not all│───────────▶────────────────────┤
└────────────────────────┘ │ GetParameters API │
└────────────────────┘
Parameters
----------
parameters: dict[str, dict]
List of parameter names, and any optional overrides
transform: str, optional
Transforms the content from a JSON object ('json') or base64 binary string ('binary')
decrypt: bool, optional
If the parameter values should be decrypted
max_age: int, optional
Maximum age of the cached value
raise_on_error: bool
Whether to fail-fast or fail gracefully by including "_errors" key in the response, by default True
Raises
------
GetParameterError
When the parameter provider fails to retrieve a parameter value for a given name.
When "_errors" reserved key is in parameters to be fetched from SSM.
"""
# If max_age is not set, resolve it from the environment variable, defaulting to DEFAULT_MAX_AGE_SECS
max_age = resolve_max_age(env=os.getenv(constants.PARAMETERS_MAX_AGE_ENV, DEFAULT_MAX_AGE_SECS), choice=max_age)
# If decrypt is not set, resolve it from the environment variable, defaulting to False
decrypt = resolve_truthy_env_var_choice(
env=os.getenv(constants.PARAMETERS_SSM_DECRYPT_ENV, "false"),
choice=decrypt,
)
# Init potential batch/decrypt batch responses and errors
batch_ret: dict[str, Any] = {}
decrypt_ret: dict[str, Any] = {}
batch_err: list[str] = []
decrypt_err: list[str] = []
response: dict[str, Any] = {}
# NOTE: We fail early to avoid unintended graceful errors being replaced with their '_errors' param values
self._raise_if_errors_key_is_present(parameters, self._ERRORS_KEY, raise_on_error)
batch_params, decrypt_params = self._split_batch_and_decrypt_parameters(parameters, transform, max_age, decrypt)
# NOTE: We need to find out whether all parameters must be decrypted or not to know which API to use
## Logic:
##
## GetParameters API -> When decrypt is used for all parameters in the the batch
## GetParameter API -> When decrypt is used for one or more in the batch
if len(decrypt_params) != len(parameters):
decrypt_ret, decrypt_err = self._get_parameters_by_name_with_decrypt_option(decrypt_params, raise_on_error)
batch_ret, batch_err = self._get_parameters_batch_by_name(batch_params, raise_on_error, decrypt=False)
else:
batch_ret, batch_err = self._get_parameters_batch_by_name(decrypt_params, raise_on_error, decrypt=True)
# Fail-fast disabled, let's aggregate errors under "_errors" key so they can handle gracefully
if not raise_on_error:
response[self._ERRORS_KEY] = [*decrypt_err, *batch_err]
return {**response, **batch_ret, **decrypt_ret}
def _get_parameters_by_name_with_decrypt_option(
self,
batch: dict[str, dict],
raise_on_error: bool,
) -> tuple[dict, list]:
response: dict[str, Any] = {}
errors: list[str] = []
# Decided for single-thread as it outperforms in 128M and 1G + reduce timeout risk
# see: https://github.com/aws-powertools/powertools-lambda-python/issues/1040#issuecomment-1299954613
for parameter, options in batch.items():
try:
response[parameter] = self.get(parameter, options["max_age"], options["transform"], options["decrypt"])
except GetParameterError:
if raise_on_error:
raise
errors.append(parameter)
continue
return response, errors
def _get_parameters_batch_by_name(
self,
batch: dict[str, dict],
raise_on_error: bool = True,
decrypt: bool = False,
) -> tuple[dict, list]:
"""Slice batch and fetch parameters using GetParameters by max permitted"""
errors: list[str] = []
# Fetch each possible batch param from cache and return if entire batch is cached
cached_params = self._get_parameters_by_name_from_cache(batch)
if len(cached_params) == len(batch):
return cached_params, errors
# Slice batch by max permitted GetParameters call
batch_ret, errors = self._get_parameters_by_name_in_chunks(batch, cached_params, raise_on_error, decrypt)
return {**cached_params, **batch_ret}, errors
def _get_parameters_by_name_from_cache(self, batch: dict[str, dict]) -> dict[str, Any]:
"""Fetch each parameter from batch that hasn't been expired"""
cache = {}
for name, options in batch.items():
cache_key = (name, options["transform"])
if self.has_not_expired_in_cache(cache_key):
cache[name] = self.store[cache_key].value
return cache
def _get_parameters_by_name_in_chunks(
self,
batch: dict[str, dict],
cache: dict[str, Any],
raise_on_error: bool,
decrypt: bool = False,
) -> tuple[dict, list]:
"""Take out differences from cache and batch, slice it and fetch from SSM"""
response: dict[str, Any] = {}
errors: list[str] = []
diff = {key: value for key, value in batch.items() if key not in cache}
for chunk in slice_dictionary(data=diff, chunk_size=self._MAX_GET_PARAMETERS_ITEM):
response, possible_errors = self._get_parameters_by_name(
parameters=chunk,
raise_on_error=raise_on_error,
decrypt=decrypt,
)
response.update(response)
errors.extend(possible_errors)
return response, errors
def _get_parameters_by_name(
self,
parameters: dict[str, dict],
raise_on_error: bool = True,
decrypt: bool = False,
) -> tuple[dict[str, Any], list[str]]:
"""Use SSM GetParameters to fetch parameters, hydrate cache, and handle partial failure
Parameters
----------
parameters : dict[str, dict]
Parameters to fetch
raise_on_error : bool, optional
Whether to fail-fast or fail gracefully by including "_errors" key in the response, by default True
Returns
-------
dict[str, Any]
Retrieved parameters as key names and their values
Raises
------
GetParameterError
When one or more parameters failed on fetching, and raise_on_error is enabled
"""
ret: dict[str, Any] = {}
batch_errors: list[str] = []
parameter_names = list(parameters.keys())
# All params in the batch must be decrypted
# we return early if we hit an unrecoverable exception like InvalidKeyId/InternalServerError
# everything else should technically be recoverable as GetParameters is non-atomic
try:
if decrypt:
response = self.client.get_parameters(Names=parameter_names, WithDecryption=True)
else:
response = self.client.get_parameters(Names=parameter_names)
except (self.client.exceptions.InvalidKeyId, self.client.exceptions.InternalServerError):
return ret, parameter_names
batch_errors = self._handle_any_invalid_get_parameter_errors(response, raise_on_error)
transformed_params = self._transform_and_cache_get_parameters_response(response, parameters, raise_on_error)
return transformed_params, batch_errors
def _transform_and_cache_get_parameters_response(
self,
api_response: GetParametersResultTypeDef,
parameters: dict[str, Any],
raise_on_error: bool = True,
) -> dict[str, Any]:
response: dict[str, Any] = {}
for parameter in api_response["Parameters"]:
name = parameter["Name"]
value = parameter["Value"]
options = parameters[name]
transform = options.get("transform")
# NOTE: If transform is set, we do it before caching to reduce number of operations
if transform:
value = transform_value(name, value, transform, raise_on_error) # type: ignore
_cache_key = (name, options["transform"])
self.add_to_cache(key=_cache_key, value=value, max_age=options["max_age"])
response[name] = value
return response
@staticmethod
def _handle_any_invalid_get_parameter_errors(
api_response: GetParametersResultTypeDef,
raise_on_error: bool = True,
) -> list[str]:
"""GetParameters is non-atomic. Failures don't always reflect in exceptions so we need to collect."""
failed_parameters = api_response["InvalidParameters"]
if failed_parameters:
if raise_on_error:
raise GetParameterError(f"Failed to fetch parameters: {failed_parameters}")
return failed_parameters
return []
@staticmethod
def _split_batch_and_decrypt_parameters(
parameters: dict[str, dict],
transform: TransformOptions,
max_age: int,
decrypt: bool,
) -> tuple[dict[str, dict], dict[str, dict]]:
"""Split parameters that can be fetched by GetParameters vs GetParameter
Parameters
----------
parameters : dict[str, dict]
Parameters containing names as key and optional config override as value
transform : TransformOptions
Transform configuration
max_age : int
How long to cache a parameter for
decrypt : bool
Whether to use KMS to decrypt a parameter
Returns
-------
tuple[dict[str, dict], dict[str, dict]]
GetParameters and GetParameter parameters dict along with their overrides/globals merged
"""
batch_parameters: dict[str, dict] = {}
decrypt_parameters: dict[str, Any] = {}
for parameter, options in parameters.items():
# NOTE: TypeDict later
_overrides = options or {}
_overrides["transform"] = _overrides.get("transform") or transform
# These values can be falsy (False, 0)
if "decrypt" not in _overrides:
_overrides["decrypt"] = decrypt
if "max_age" not in _overrides:
_overrides["max_age"] = max_age
# NOTE: Split parameters who have decrypt OR have it global
if _overrides["decrypt"]:
decrypt_parameters[parameter] = _overrides
else:
batch_parameters[parameter] = _overrides
return batch_parameters, decrypt_parameters
@staticmethod
def _raise_if_errors_key_is_present(parameters: dict, reserved_parameter: str, raise_on_error: bool):
"""Raise GetParameterError if fail-fast is disabled and '_errors' key is in parameters batch"""
if not raise_on_error and reserved_parameter in parameters:
raise GetParameterError(
f"You cannot fetch a parameter named '{reserved_parameter}' in graceful error mode.",
)
@overload
def get_parameter(
name: str,
transform: None = None,
decrypt: bool | None = None,
force_fetch: bool = False,
max_age: int | None = None,
**sdk_options,
) -> str: ...
@overload
def get_parameter(
name: str,
transform: Literal["json"],
decrypt: bool | None = None,
force_fetch: bool = False,
max_age: int | None = None,
**sdk_options,
) -> dict: ...
@overload
def get_parameter(
name: str,
transform: Literal["binary"],
decrypt: bool | None = None,
force_fetch: bool = False,
max_age: int | None = None,
**sdk_options,
) -> str | bytes | dict: ...
@overload
def get_parameter(
name: str,
transform: Literal["auto"],
decrypt: bool | None = None,
force_fetch: bool = False,
max_age: int | None = None,
**sdk_options,
) -> bytes: ...
def get_parameter(
name: str,
transform: TransformOptions = None,
decrypt: bool | None = None,
force_fetch: bool = False,
max_age: int | None = None,
**sdk_options,
) -> str | bytes | dict:
"""
Retrieve a parameter value from AWS Systems Manager (SSM) Parameter Store
Parameters
----------
name: str
Name of the parameter
transform: str, optional
Transforms the content from a JSON object ('json') or base64 binary string ('binary')
decrypt: bool, optional
If the parameter values should be decrypted
force_fetch: bool, optional
Force update even before a cached item has expired, defaults to False
max_age: int, optional
Maximum age of the cached value
sdk_options: dict, optional
Dictionary of options that will be passed to the Parameter Store get_parameter API call
Raises
------
GetParameterError
When the parameter provider fails to retrieve a parameter value for
a given name.
TransformParameterError
When the parameter provider fails to transform a parameter value.
Example
-------
**Retrieves a parameter value from Systems Manager Parameter Store**
>>> from aws_lambda_powertools.utilities.parameters import get_parameter
>>>
>>> value = get_parameter("/my/parameter")
>>>
>>> print(value)
My parameter value
**Retrieves a parameter value and decodes it using a Base64 decoder**
>>> from aws_lambda_powertools.utilities.parameters import get_parameter
>>>
>>> value = get_parameter("/my/parameter", transform='binary')
>>>
>>> print(value)
My parameter value
"""
# Only create the provider if this function is called at least once
if "ssm" not in DEFAULT_PROVIDERS:
DEFAULT_PROVIDERS["ssm"] = SSMProvider()
# If max_age is not set, resolve it from the environment variable, defaulting to DEFAULT_MAX_AGE_SECS
max_age = resolve_max_age(env=os.getenv(constants.PARAMETERS_MAX_AGE_ENV, DEFAULT_MAX_AGE_SECS), choice=max_age)
# If decrypt is not set, resolve it from the environment variable, defaulting to False
decrypt = resolve_truthy_env_var_choice(
env=os.getenv(constants.PARAMETERS_SSM_DECRYPT_ENV, "false"),
choice=decrypt,
)
return DEFAULT_PROVIDERS["ssm"].get(
name=name,
max_age=max_age,
transform=transform,
force_fetch=force_fetch,
decrypt=decrypt,
**sdk_options,
)
@overload
def get_parameters(
path: str,
transform: None = None,
recursive: bool = True,
decrypt: bool | None = None,
force_fetch: bool = False,
max_age: int | None = None,
raise_on_transform_error: bool = False,
**sdk_options,
) -> dict[str, str]: ...
@overload
def get_parameters(
path: str,
transform: Literal["json"],
recursive: bool = True,
decrypt: bool | None = None,
force_fetch: bool = False,
max_age: int | None = None,
raise_on_transform_error: bool = False,
**sdk_options,
) -> dict[str, dict]: ...
@overload
def get_parameters(
path: str,
transform: Literal["binary"],
recursive: bool = True,
decrypt: bool | None = None,
force_fetch: bool = False,
max_age: int | None = None,
raise_on_transform_error: bool = False,
**sdk_options,
) -> dict[str, bytes]: ...
@overload
def get_parameters(
path: str,
transform: Literal["auto"],
recursive: bool = True,
decrypt: bool | None = None,
force_fetch: bool = False,
max_age: int | None = None,
raise_on_transform_error: bool = False,
**sdk_options,
) -> dict[str, str] | dict[str, bytes] | dict[str, dict]: ...
def get_parameters(
path: str,
transform: TransformOptions = None,
recursive: bool = True,
decrypt: bool | None = None,
force_fetch: bool = False,
max_age: int | None = None,
raise_on_transform_error: bool = False,
**sdk_options,
) -> dict[str, str] | dict[str, bytes] | dict[str, dict]:
"""
Retrieve multiple parameter values from AWS Systems Manager (SSM) Parameter Store
For readability, we strip the path prefix name in the response.
Parameters
----------
path: str
Path to retrieve the parameters
transform: str, optional
Transforms the content from a JSON object ('json') or base64 binary string ('binary')
recursive: bool, optional
If this should retrieve the parameter values recursively or not, defaults to True
decrypt: bool, optional
If the parameter values should be decrypted
force_fetch: bool, optional
Force update even before a cached item has expired, defaults to False
max_age: int, optional
Maximum age of the cached value
raise_on_transform_error: bool, optional
Raises an exception if any transform fails, otherwise this will
return a None value for each transform that failed
sdk_options: dict, optional
Dictionary of options that will be passed to the Parameter Store get_parameters_by_path API call
Raises
------
GetParameterError
When the parameter provider fails to retrieve parameter values for
a given path.
TransformParameterError
When the parameter provider fails to transform a parameter value.
Example
-------
**Retrieves parameter values from Systems Manager Parameter Store**
>>> from aws_lambda_powertools.utilities.parameters import get_parameter
>>>
>>> values = get_parameters("/my/path/prefix")
>>>
>>> for key, value in values.items():
... print(key, value)
config Parameter value (/my/path/prefix/config)
webhook/config Parameter value (/my/path/prefix/webhook/config)
**Retrieves parameter values and decodes them using a Base64 decoder**
>>> from aws_lambda_powertools.utilities.parameters import get_parameter
>>>
>>> values = get_parameters("/my/path/prefix", transform='binary')
"""
# Only create the provider if this function is called at least once
if "ssm" not in DEFAULT_PROVIDERS:
DEFAULT_PROVIDERS["ssm"] = SSMProvider()
# If max_age is not set, resolve it from the environment variable, defaulting to DEFAULT_MAX_AGE_SECS
max_age = resolve_max_age(env=os.getenv(constants.PARAMETERS_MAX_AGE_ENV, DEFAULT_MAX_AGE_SECS), choice=max_age)
# If decrypt is not set, resolve it from the environment variable, defaulting to False
decrypt = resolve_truthy_env_var_choice(
env=os.getenv(constants.PARAMETERS_SSM_DECRYPT_ENV, "false"),
choice=decrypt,
)
return DEFAULT_PROVIDERS["ssm"].get_multiple(
path=path,
max_age=max_age,
transform=transform,
raise_on_transform_error=raise_on_transform_error,
force_fetch=force_fetch,
recursive=recursive,
decrypt=decrypt,
**sdk_options,
)
def set_parameter(