import { Client, Worker } from '@temporalio/core-bridge';
import { NativeConnectionOptions } from './connection-options';
/**
 * A Native Connection object that delegates calls to the Rust Core binary extension.
 *
 * A Worker must use this class to connect to the server.
 *
 * Do not confuse this connection class with `@temporalio/client`'s Connection.
 */
export declare class NativeConnection {
    private nativeClient;
    /**
     * referenceHolders is used internally by the framework, it can be accessed with `extractReferenceHolders` (below)
     */
    private readonly referenceHolders;
    /**
     * nativeClient is intentionally left private, framework code can access it with `extractNativeClient` (below)
     */
    protected constructor(nativeClient: Client);
    /**
     * @deprecated use `connect` instead
     */
    static create(options?: NativeConnectionOptions): Promise<NativeConnection>;
    /**
     * Eagerly connect to the Temporal server and return a NativeConnection instance
     */
    static connect(options?: NativeConnectionOptions): Promise<NativeConnection>;
    /**
     * Close this connection.
     *
     * Make sure any Workers using this connection are stopped before calling
     * this method or it will throw an {@link IllegalStateError}
     */
    close(): Promise<void>;
    /**
     * Mapping of gRPC metadata (HTTP headers) to send with each request to the server.
     *
     * Use {@link NativeConnectionOptions.metadata} to set the initial metadata for client creation.
     */
    setMetadata(metadata: Record<string, string>): Promise<void>;
    /**
     * Update the API key for this client. This is only set if `metadata` doesn't already have an
     * "authorization" key.
     *
     * Use {@link NativeConnectionOptions.apiKey} to set the initial metadata for client creation.
     */
    setApiKey(apiKey: string): Promise<void>;
}
/**
 * Extract the private native client instance from a `NativeConnection` instance.
 *
 * Only meant to be used by the framework.
 */
export declare function extractNativeClient(conn: NativeConnection): Client;
/**
 * Extract the private referenceHolders set from a `NativeConnection` instance.
 *
 * Only meant to be used by the framework.
 */
export declare function extractReferenceHolders(conn: NativeConnection): Set<Worker>;
/**
 * Internal class used when a Worker directly instantiates a connection with no external references.
 *
 * This class is only used as a "marker" during Worker shutdown to decide whether to close the connection.
 */
export declare class InternalNativeConnection extends NativeConnection {
}