@aws-lambda-powertools/metrics/lib/esm/MetadataStore.js

The metrics package for the Powertools for AWS Lambda (TypeScript) library

import '@aws/lambda-invoke-store';
import { shouldUseInvokeStore } from '@aws-lambda-powertools/commons/utils/env';
/**
 * Manages storage of metrics #metadata with automatic context detection.
 *
 * This class abstracts the storage mechanism for metrics, automatically
 * choosing between AsyncLocalStorage (when in async context) and a fallback
 * object (when outside async context). The decision is made at runtime on
 * every method call to support Lambda's transition to async contexts.
 */
class MetadataStore {
    #metadataKey = Symbol('powertools.metrics.metadata');
    #fallbackStorage = {};
    #getStorage() {
        if (!shouldUseInvokeStore()) {
            return this.#fallbackStorage;
        }
        if (globalThis.awslambda?.InvokeStore === undefined) {
            throw new Error('InvokeStore is not available');
        }
        const store = globalThis.awslambda.InvokeStore;
        let stored = store.get(this.#metadataKey);
        if (stored == null) {
            stored = {};
            store.set(this.#metadataKey, stored);
        }
        return stored;
    }
    set(key, value) {
        this.#getStorage()[key] = value;
        return value;
    }
    getAll() {
        return { ...this.#getStorage() };
    }
    clear() {
        if (!shouldUseInvokeStore()) {
            this.#fallbackStorage = {};
            return;
        }
        if (globalThis.awslambda?.InvokeStore === undefined) {
            throw new Error('InvokeStore is not available');
        }
        const store = globalThis.awslambda.InvokeStore;
        store.set(this.#metadataKey, {});
    }
}
export { MetadataStore };