import { APIGatewayProxyResult } from "aws-lambda";
import { DynamoDBDocument } from "@aws-sdk/lib-dynamodb";
export declare const commonHeaders: {
    "Access-Control-Allow-Origin": string;
    "Access-Control-Allow-Credentials": boolean;
    "Cache-Control": string;
};
export interface GeoprocessingTask<ResultType = any> {
    id: string;
    service: string;
    location: string;
    startedAt: string;
    duration?: number;
    logUriTemplate: string;
    geometryUri: string;
    status: GeoprocessingTaskStatus;
    /** websocket url */
    wss: string;
    data?: ResultType;
    error?: string;
    estimate: number;
    disableCache?: boolean;
}
export interface MetricGroupItem<ResultType = any> {
    duration?: number;
    status: GeoprocessingTaskStatus;
    data?: ResultType;
}
export interface RootTaskItem<ResultType = any> extends MetricGroupItem<ResultType> {
    metricGroupItems: string[];
}
export declare enum GeoprocessingTaskStatus {
    Pending = "pending",
    Completed = "completed",
    Failed = "failed"
}
/**
 * Task model responsible for managing task results and estimates in DynamoDB
 */
export default class TasksModel {
    /** task table */
    table: string;
    /** task estimate table */
    estimatesTable: string;
    /** database client */
    db: DynamoDBDocument;
    constructor(table: string, estimatesTable: string, db: DynamoDBDocument);
    init(service: string, id?: string, 
    /** websocket url */
    wss?: string, startedAt?: string, duration?: number, status?: GeoprocessingTaskStatus): GeoprocessingTask<any>;
    create(service: string, options?: {
        /** Unique identifier for this task, used as cache key.  If not provided a uuid is created */
        id?: string;
        /** websocket url */
        wss?: string;
        disableCache?: boolean;
    }): Promise<GeoprocessingTask<any>>;
    /**
     * @param task
     * @param results - JSON serializable object, with no string larger than 400KB without a space character.  Spaces are used to chunk result
     * @param options
     * @returns
     */
    complete(task: GeoprocessingTask, results: any, options?: {
        minSplitSizeBytes?: number;
    }): Promise<APIGatewayProxyResult>;
    updateEstimate(task: GeoprocessingTask): Promise<number | undefined>;
    fail(task: GeoprocessingTask, errorDescription: string, error?: Error): Promise<APIGatewayProxyResult>;
    get(service: string, taskId: string): Promise<GeoprocessingTask | undefined>;
    getMeanEstimate(task: GeoprocessingTask): Promise<number>;
    /**
     * Transform valid JSON object into string and break into pieces no larger than minSplitSizeBytes
     * @param rootResult
     * @param minSplitSizeBytes maximum return substring size in bytes (default 350KB, below 400KB dynamodb limit)
     * @returns array of JSON substrings, in order for re-assembly
     */
    private toJsonStrings;
    /**
     * Given array of partial JSON strings, joins them together and parses the result
     */
    private fromJsonStrings;
}