LaunchDarkly

Load a LaunchDarkly feature flag’s value as config, with native watch via the LaunchDarkly streaming SDK.

Install

go get github.com/xavidop/mamori/providers/launchdarkly

import _ "github.com/xavidop/mamori/providers/launchdarkly"

Using the ref

A launchdarkly:// ref points at one flag key. The flag is evaluated for a fixed evaluation context (your service), and its variation becomes the value.

launchdarkly://<flag-key>

The variation maps to bytes by type: a boolean flag resolves to true / false, a string flag to its string, a number to its decimal form, and a JSON flag to its JSON encoding. A flag key that does not exist resolves to not-found, so default: / optional:"true" applies.

Examples

• launchdarkly://enable-new-checkout on a boolean flag resolves to true or false - pair it with a bool field.
• launchdarkly://max-batch-size on a number flag resolves to e.g. 250 - pair it with an int field and a validate rule.
• launchdarkly://pricing-config on a JSON flag resolves to the JSON, which you can decode with flatten:"json".

type Config struct {
	NewCheckout bool          `source:"launchdarkly://enable-new-checkout"`
	Pricing     PricingConfig `source:"launchdarkly://pricing-config" flatten:"json"`
}

The evaluation context defaults to a stable key (mamori); override it with WithContextKey.

Watch

Watch uses the SDK flag tracker: LaunchDarkly streams flag changes, and mamori emits an update the instant the flag’s value for your context changes. This is a genuine push, not polling.

Configuration

import ldprov "github.com/xavidop/mamori/providers/launchdarkly"

mamori.WithProvider(ldprov.New(ldprov.WithSDKKey(os.Getenv("LAUNCHDARKLY_SDK_KEY"))))

Verified with an injected fake evaluator (including value-change subscriptions and not-found), so the watch conformance checks run without a live LaunchDarkly. A real-SDK test is provided behind //go:build integration.