openfeature-provider-aws-ssm 0.1.1

OpenFeature Python AWS Systems Manager Parameter Store Provider

OpenFeature AWS SSM Parameter Store Provider

This provider enables the use of AWS Systems Manager (SSM) Parameter Store as a backend for OpenFeature feature flags in Python.

Installation

pip install openfeature-provider-aws-ssm

For async support:

pip install openfeature-provider-aws-ssm[async]

Usage

Basic Usage

from openfeature import api
from openfeature.contrib.provider.awsssm import AwsSsmProvider

# Initialize the provider
provider = AwsSsmProvider()

# Set the provider
api.set_provider(provider)

# Get a client
client = api.get_client()

# Evaluate a flag
is_enabled = client.get_boolean_value("my-feature-flag", default_value=False)

With Configuration

from botocore.config import Config
from openfeature.contrib.provider.awsssm import (
    AwsSsmProvider,
    AwsSsmProviderConfig,
    CacheConfig,
)

config = AwsSsmProviderConfig(
    config=Config(
        region_name="us-west-2",
        retries={"max_attempts": 10, "mode": "standard"},
        connect_timeout=5,
        read_timeout=60,
    ),
    enable_decryption=True,  # For SecureString parameters
    cache_config=CacheConfig(
        cache_type="ttl",
        size=1000,
        ttl=300,  # 5 minutes in seconds
    ),
)

provider = AwsSsmProvider(config=config)
api.set_provider(provider)

Async Usage

from openfeature import api
from openfeature.contrib.provider.awsssm import AwsSsmProvider

provider = AwsSsmProvider()
api.set_provider(provider)

client = api.get_client()

# Async flag evaluation
is_enabled = await client.get_boolean_value_async(
    "my-feature-flag", default_value=False
)

Flag Key Mapping

Flag keys are mapped to SSM parameter names with the following rules:

• If the flag key starts with /, it's used as-is
• Otherwise, a leading / is automatically prepended

Examples:

• Flag key my-feature → Parameter /my-feature
• Flag key /app/prod/feature → Parameter /app/prod/feature

Flag Types

The provider supports all OpenFeature flag types:

OpenFeature Type	SSM Parameter Value	Parsing Rules
Boolean	"true" or "false"	Case-insensitive. Other values raise TypeMismatchError
String	Any string	Returned as-is
Integer	"42", "-10"	Parsed with int(). Invalid values raise TypeMismatchError
Float	"3.14", "-2.5"	Parsed with float(). Invalid values raise TypeMismatchError
Object	Valid JSON	Parsed as JSON object or array. Invalid JSON or primitives raise ParseError

Configuration Options

AwsSsmProviderConfig

Parameter	Type	Default	Description
config	botocore.config.Config	None	boto3 Config object (includes region_name, retries, timeouts, etc.)
endpoint_url	str	None	Custom SSM endpoint URL (for testing with LocalStack/moto)
enable_decryption	bool	False	Whether to decrypt SecureString parameters
cache_config	CacheConfig	CacheConfig()	Configuration for the local cache

CacheConfig

The provider supports multiple caching strategies to optimize performance. To disable caching entirely, pass cache_config=None when creating the provider config.

Parameter	Type	Default	Description
cache_type	Literal["lru", "ttl"]	"lru"	Type of cache: "lru" (size-based) or "ttl" (time-based)
ttl	int	300	Time-to-live for cached items in seconds (only used with cache_type="ttl")
size	int	1000	Maximum number of items in the cache

Cache Types

• "lru" (default): Least Recently Used cache with size-based eviction only. Cached values persist until evicted due to size limits.
• "ttl": Time-To-Live cache with both time-based expiration AND size-based eviction. Cached values automatically expire after the configured TTL, even if space remains in the cache.

Cache Examples

# LRU cache (default) - size-based eviction only
cache_config=CacheConfig(cache_type="lru", size=500)

# TTL cache - expires after 60 seconds
cache_config=CacheConfig(cache_type="ttl", ttl=60, size=500)

# No caching - pass cache_config=None to the provider config
provider_config = AwsSsmProviderConfig(cache_config=None)

For more information on the Config object, see the boto3 configuration documentation.

License

Apache 2.0 - See LICENSE for more information.