LaunchDarkly OpenFeature Provider for Python Server SDK

0.5.1 verified Mon Apr 27 auth: no python

An OpenFeature provider that bridges the LaunchDarkly Python server SDK with the OpenFeature API, enabling feature flag evaluation through the standard OpenFeature interface. Current version 0.5.1, requires Python <4.0,>=3.9. Pre-1.0 release with active development.

pip install launchdarkly-openfeature-server

Common errors

error ModuleNotFoundError: No module named 'launchdarkly_openfeature' ↓

cause Installed wrong package or missing dependency.

fix

Install via: pip install launchdarkly-openfeature-server

error ImportError: cannot import name 'LaunchDarklyProvider' from 'launchdarkly_openfeature' ↓

cause Importing from wrong submodule.

fix

Use: from launchdarkly_openfeature.server import LaunchDarklyProvider

error AttributeError: 'NoneType' object has no attribute 'get_boolean_value' ↓

cause OpenFeature client not properly initialized or provider not set.

fix

Ensure api.set_provider() is called before api.get_client().

Warnings

breaking The provider requires an initialized LDClient instance. Do not use ldclient.set_sdk_key() global initialization; the provider expects an explicit client. ↓

fix Instantiate LDClient with config and pass it to LaunchDarklyProvider.

gotcha The library is pre-1.0 (0.x.y). APIs may change without major version bump. Pin to exact version in production. ↓

fix Pin exact version in requirements: launchdarkly-openfeature-server==0.5.1

deprecated Do not use ldclient.get() global client. The provider expects an explicit LDClient instance. ↓

fix Create explicit LDClient and pass to provider.

Imports

LaunchDarklyProvider

wrong

from launchdarkly_openfeature import LaunchDarklyProvider

correct

from launchdarkly_openfeature.server import LaunchDarklyProvider

Provider is in the 'server' submodule, not top-level.

Quickstart

Simple example showing initialization and flag evaluation.

import os
from ldclient import Config, LDClient
from openfeature import api
from openfeature.evaluation_context import EvaluationContext
from launchdarkly_openfeature.server import LaunchDarklyProvider

# Initialize LD client
ld_config = Config(os.environ.get('LAUNCHDARKLY_SDK_KEY', ''))
ld_client = LDClient(config=ld_config)

# Set provider in OpenFeature
api.set_provider(LaunchDarklyProvider(ld_client))

# Get OpenFeature client
client = api.get_client()

# Evaluate a flag
targeting_key = 'user-key'
ctx = EvaluationContext(targeting_key=targeting_key, attributes={'email': 'user@example.com'})
result = client.get_boolean_value('my-flag', default_value=False, evaluation_context=ctx)
print(f'Flag value: {result}')