/**
 * The injection point for a consumer's OWN secret persistence (e.g. sealing
 * the secret in the consumer's own vault) — mirrors `ApolloSigner`'s
 * bring-your-own-implementation shape. `PythiaConnector` (a later addition)
 * is the sole decider of staleness/expiry; this store holds and returns
 * whatever entry it was given verbatim, with no TTL logic of its own.
 */
/** A cached connector secret plus the epoch-ms timestamp it expires at. */
export interface SecretStorage {
    load(): Promise<{
        secret: string;
        expiresAt: number;
    } | null>;
    save(entry: {
        secret: string;
        expiresAt: number;
    }): Promise<void>;
    clear(): Promise<void>;
}
/** Trivial default `SecretStorage` backed by a single in-process field — no
 * persistence across restarts. Lets the SDK be used standalone without
 * forcing every consumer to write a storage adapter before their first test. */
export declare class InMemorySecretStorage implements SecretStorage {
    private entry;
    load(): Promise<{
        secret: string;
        expiresAt: number;
    } | null>;
    save(entry: {
        secret: string;
        expiresAt: number;
    }): Promise<void>;
    clear(): Promise<void>;
}