@redpennon/node-sdk

Thin HTTP client for the RedPennon feature flag evaluation API.

Installation

npm install @redpennon/node-sdk

Requires Node 20+. No runtime dependencies — uses the global fetch.

Quick start

import { RedPennonClient } from "@redpennon/node-sdk";

const client = new RedPennonClient({ apiKey: "YOUR_ENV_API_KEY" });

// Simple: get the resolved value or your default on any failure.
const enabled = await client.variableValue("dark-mode-enabled", {
  default: false,
});

// With user context (for targeting rules).
const user = { id: "user_123", email: "[email protected]" };
const enabled = await client.variableValue("dark-mode-enabled", {
  default: false,
  user,
});

// Full result: value + variation + reason.
const result = await client.variable("dark-mode-enabled", { user });
console.log(result.value, result.variation, result.reason);

// Batch: resolve many flags in one round-trip.
const results = await client.variables(["flag-a", "flag-b"], { user });
const flagA = results["flag-a"].value;

API

new RedPennonClient({ apiKey, baseUrl?, fetchImpl? })

| Option | Type | Description | |--------|------|-------------| | apiKey | string | Environment API key from the RedPennon dashboard. | | baseUrl | string? | Override the API base URL (default: https://api.redpennon.dev). | | fetchImpl | typeof fetch? | Custom fetch — useful for testing. |

client.variableValue(key, { default, user? }) → Promise<T>

Returns the resolved value or default on any failure (network error, non-2xx, value=null). Use this in production code — your default is the load-bearing contract.

client.variable(key, { user? }) → Promise<VariableResult>

Returns the full evaluation result (value, variation, reason, feature). Throws APIError on network or non-2xx errors.

client.variables(keys, { user? }) → Promise<Record<string, VariableResult>>

Batch evaluation — one HTTP round-trip for multiple flags. Unknown keys return reason: "variable_not_found" inline rather than throwing.

Local development

npm ci
npm test
npm run build

License

MIT © RedPennon