import { ICacheClient } from "@gomomento/sdk-core";
import { BaseCache } from "@langchain/core/caches";
import { Generation } from "@langchain/core/outputs";
/**
 * The settings to instantiate the Momento standard cache.
 */
export interface MomentoCacheProps {
    /**
     * The Momento cache client.
     */
    client: ICacheClient;
    /**
     * The name of the cache to use to store the data.
     */
    cacheName: string;
    /**
     * The time to live for the cache items. If not specified,
     * the cache client default is used.
     */
    ttlSeconds?: number;
    /**
     * If true, ensure that the cache exists before returning.
     * If false, the cache is not checked for existence.
     * Defaults to true.
     */
    ensureCacheExists?: true;
}
/**
 * A cache that uses Momento as the backing store.
 * See https://gomomento.com.
 * @example
 * ```typescript
 * const cache = new MomentoCache({
 *   client: new CacheClient({
 *     configuration: Configurations.Laptop.v1(),
 *     credentialProvider: CredentialProvider.fromEnvironmentVariable({
 *       environmentVariableName: "MOMENTO_API_KEY",
 *     }),
 *     defaultTtlSeconds: 60 * 60 * 24, // Cache TTL set to 24 hours.
 *   }),
 *   cacheName: "langchain",
 * });
 * // Initialize the OpenAI model with Momento cache for caching responses
 * const model = new ChatOpenAI({
 *   model: "gpt-4o-mini",
 *   cache,
 * });
 * await model.invoke("How are you today?");
 * const cachedValues = await cache.lookup("How are you today?", "llmKey");
 * ```
 */
export declare class MomentoCache extends BaseCache {
    private client;
    private readonly cacheName;
    private readonly ttlSeconds?;
    private constructor();
    /**
     * Create a new standard cache backed by Momento.
     *
     * @param {MomentoCacheProps} props The settings to instantiate the cache.
     * @param {ICacheClient} props.client The Momento cache client.
     * @param {string} props.cacheName The name of the cache to use to store the data.
     * @param {number} props.ttlSeconds The time to live for the cache items. If not specified,
     * the cache client default is used.
     * @param {boolean} props.ensureCacheExists If true, ensure that the cache exists before returning.
     * If false, the cache is not checked for existence. Defaults to true.
     * @throws {@link InvalidArgumentError} if {@link props.ttlSeconds} is not strictly positive.
     * @returns The Momento-backed cache.
     */
    static fromProps(props: MomentoCacheProps): Promise<MomentoCache>;
    /**
     * Validate the user-specified TTL, if provided, is strictly positive.
     * @param ttlSeconds The TTL to validate.
     */
    private validateTtlSeconds;
    /**
     * Lookup LLM generations in cache by prompt and associated LLM key.
     * @param prompt The prompt to lookup.
     * @param llmKey The LLM key to lookup.
     * @returns The generations associated with the prompt and LLM key, or null if not found.
     */
    lookup(prompt: string, llmKey: string): Promise<Generation[] | null>;
    /**
     * Update the cache with the given generations.
     *
     * Note this overwrites any existing generations for the given prompt and LLM key.
     *
     * @param prompt The prompt to update.
     * @param llmKey The LLM key to update.
     * @param value The generations to store.
     */
    update(prompt: string, llmKey: string, value: Generation[]): Promise<void>;
}
