@hotmeshio/hotmesh/build/services/meshflow/handle.d.ts

Serverless Workflow

import { HotMesh } from '../hotmesh';
import { MeshFlowJobExport, ExportOptions } from '../../types/exporter';
import { JobInterruptOptions } from '../../types/job';
import { StreamError } from '../../types/stream';
import { ExporterService } from './exporter';
/**
 * The WorkflowHandleService provides methods to interact with a running
 * workflow. This includes exporting the workflow, sending signals, and
 * querying the state of the workflow. It is instanced/accessed via the
 * MeshFlow.Client class.
 *
 * @example
 * ```typescript
 * import { Client } from '@hotmeshio/hotmesh';
 * import { Client as Postgres } from 'pg';
 *
 * const client = new Client({ connection: {
 *   class: Postgres,
 *   options: { connectionString: 'postgres://user:pass@localhost:5432/db' }
 * }});
 *
 * const handle = await client.workflow.start({
 *  args: ['HotMesh'],
 *  taskQueue: 'hello-world',
 * });
 *
 * //perform actions like send a signal
 * await handle.signal('my-signal', { data: 'Hello' });
 * ```
 */
export declare class WorkflowHandleService {
    /**
     * @private
     */
    exporter: ExporterService;
    hotMesh: HotMesh;
    workflowTopic: string;
    workflowId: string;
    /**
     * @private
     */
    constructor(hotMesh: HotMesh, workflowTopic: string, workflowId: string);
    /**
     * Exports the workflow state to a JSON object.
     */
    export(options?: ExportOptions): Promise<MeshFlowJobExport>;
    /**
     * Sends a signal to the workflow. This is a way to send
     * a message to a workflow that is paused due to having
     * executed `MeshFlow.workflow.waitFor`. The workflow
     * will awaken if no other signals are pending.
     */
    signal(signalId: string, data: Record<any, any>): Promise<void>;
    /**
     * Returns the job state of the workflow. If the workflow has completed
     * this is also the job output. If the workflow is still running, this
     * is the current state of the job, but it may change depending upon
     * the activities that remain.
     */
    state(metadata?: boolean): Promise<Record<string, any>>;
    /**
     * Returns the current search state of the workflow. This is
     * different than the job state or individual activity state.
     * Search state represents name/value pairs that were added
     * to the workflow.
     */
    queryState(fields: string[]): Promise<Record<string, any>>;
    /**
     * Returns the current status of the workflow. This is a semaphore
     * value that represents the current state of the workflow, where
     * 0 is complete and a negative value represents that the flow was
     * interrupted.
     */
    status(): Promise<number>;
    /**
     * Interrupts a running workflow. Standard Job Completion tasks will
     * run. Subscribers will be notified and the job hash will be expired.
     */
    interrupt(options?: JobInterruptOptions): Promise<string>;
    /**
     * Waits for the workflow to complete and returns the result. If
     * the workflow response includes an error, this method will rethrow
     * the error, including the stack trace if available.
     * Wrap calls in a try/catch as necessary to avoid unhandled exceptions.
     */
    result<T>(config?: {
        state?: boolean;
        throwOnError?: boolean;
    }): Promise<T | StreamError>;
}