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MongoDB query language for in-memory objects

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var __defProp = Object.defineProperty; var __getOwnPropDesc = Object.getOwnPropertyDescriptor; var __getOwnPropNames = Object.getOwnPropertyNames; var __hasOwnProp = Object.prototype.hasOwnProperty; var __export = (target, all) => { for (var name in all) __defProp(target, name, { get: all[name], enumerable: true }); }; var __copyProps = (to, from, except, desc) => { if (from && typeof from === "object" || typeof from === "function") { for (let key of __getOwnPropNames(from)) if (!__hasOwnProp.call(to, key) && key !== except) __defProp(to, key, { get: () => from[key], enumerable: !(desc = __getOwnPropDesc(from, key)) || desc.enumerable }); } return to; }; var __toCommonJS = (mod) => __copyProps(__defProp({}, "__esModule", { value: true }), mod); var aggregator_exports = {}; __export(aggregator_exports, { Aggregator: () => Aggregator }); module.exports = __toCommonJS(aggregator_exports); var import_internal = require("./core/_internal"); var import_lazy = require("./lazy"); var import_util = require("./util"); class Aggregator { #pipeline; #options; /** * Creates an instance of the Aggregator class. * * @param pipeline - An array of objects representing the aggregation pipeline stages. * @param options - Optional configuration settings for the aggregator. */ constructor(pipeline, options) { this.#pipeline = pipeline; this.#options = import_internal.ComputeOptions.init(options); } /** * Processes a collection through an aggregation pipeline and returns an iterator * for the transformed results. * * @param collection - The input collection to process. This can be any source * that implements the `Source` interface. * @param options - Optional configuration for processing. If not provided, the * default options of the aggregator instance will be used. * @returns An iterator that yields the results of the aggregation pipeline. * * @throws Will throw an error if: * - A pipeline stage contains more than one operator. * - The `$documents` operator is not the first stage in the pipeline. * - An unregistered pipeline operator is encountered. */ stream(collection, options) { let iter = (0, import_lazy.Lazy)(collection); const opts = options ?? this.#options; const mode = opts.processingMode; if (mode & import_internal.ProcessingMode.CLONE_INPUT) iter.map((o) => (0, import_util.cloneDeep)(o)); iter = this.#pipeline.map((stage, i) => { const keys = Object.keys(stage); (0, import_util.assert)( keys.length === 1, `aggregation stage must have single operator, got ${keys.toString()}.` ); const name = keys[0]; (0, import_util.assert)( name !== "$documents" || i == 0, "$documents must be first stage in pipeline." ); const op = opts.context.getOperator( import_internal.OpType.PIPELINE, name ); (0, import_util.assert)(!!op, `unregistered pipeline operator ${name}.`); return [op, stage[name]]; }).reduce((acc, [op, expr]) => op(acc, expr, opts), iter); if (mode & import_internal.ProcessingMode.CLONE_OUTPUT) iter.map((o) => (0, import_util.cloneDeep)(o)); return iter; } /** * Executes the aggregation pipeline on the provided collection and returns the resulting array. * * @template T - The type of the objects in the resulting array. * @param collection - The input data source to run the aggregation on. * @param options - Optional settings to customize the aggregation behavior. * @returns An array of objects of type `T` resulting from the aggregation. */ run(collection, options) { return this.stream(collection, options).collect(); } } // Annotate the CommonJS export names for ESM import in node: 0 && (module.exports = { Aggregator });