"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.parseAndBuildModel = exports.requestAndBuildModel = void 0; const dependencies_1 = require("../dependencies"); const optional_1 = require("../types/optional"); const fetch_timing_metrics_builder_1 = require("./fetch-timing-metrics-builder"); /** * Returns an object graph guaranteed to have a `FetchTimingMetricsBuilder` object. * * If a `FetchTimingMetricsBuilder` already exists, the same object graph is returned. * * If it doesn't exist, a new object graph is returned, which has a new `FetchTimingMetricsBuilder` added to it. */ function ensureFetchTimingMetricsBuilderExists(objectGraph, errorIfNotFound) { const optionalBuilder = objectGraph.optional(fetch_timing_metrics_builder_1.fetchTimingMetricsBuilderType); if ((0, optional_1.isSome)(optionalBuilder)) { return objectGraph; } else { if (errorIfNotFound) { throw new Error("Could not find FetchTimingMetricsBuilder in the object graph"); } return objectGraph.adding(fetch_timing_metrics_builder_1.fetchTimingMetricsBuilderType, new fetch_timing_metrics_builder_1.FetchTimingMetricsBuilder()); } } /** * Orchestrates the flow to make a network request and then build the view model, * capturing timing points around the model building step, and then * adding performance metrics data to the final result. * * **Important** * * When using this method, it is the responsibility of the `requester` to instrument the network times and parsing times * using a `FetchTimingMetricsBuilder` which is in the object graph. * * A simplified implementation of a requester function might look like this: ``` import * as types from "@jet/environment/types/globals/types" import { fetchTimingMetricsBuilderType } from "@jet/environment/metrics"; export async function requestFromAPI(request: FetchRequest, objectGraph: ObjectGraph): Promise { const net = inject(types.net, objectGraph); const fetchResponse = await net.fetch(request); const fetchTimingMetricsBuilder = inject(fetchTimingMetricsBuilderType, objectGraph); return fetchTimingMetricsBuilder.measureParsing(fetchResponse, (response) => { const parsedBody = JSON.parse(response.body); return new MyParsedModel(parsedBody); }); } ``` * This approach supports a common pattern in our adopters in which the code that coordinates the fetch of the network request * is tightly coupled to the code which parses the response. * * For an alternative approach which includes orchestrating the parsing step, use `parseAndBuildModel()`. * * @param request - The request object to pass to the `requester` function. * @param objectGraph - Object graph that can be used to pass data to the `requester` and `modelBuilder` steps. * The object graph must contain a `FetchTimingMetricsBuilder` that the `requester` will use to collect network times and parsing times. * @param requester - A function which can make a network request, and return a `ResponseType` which can be used by the `modelBuilder`. * @param modelBuilder - A step that takes the output of the `requester` step, and builds the view model. * This parameter supports both synchronous and asynchronous functions. * @returns The view model. */ async function requestAndBuildModel(request, objectGraph, requester, modelBuilder) { const modifiedObjectGraph = ensureFetchTimingMetricsBuilderExists(objectGraph, true); const response = await requester(request, modifiedObjectGraph); return await constructAndDecorateModel(response, modifiedObjectGraph, modelBuilder); } exports.requestAndBuildModel = requestAndBuildModel; /** * Orchestrates the flow to parse a `FetchResponse` and then build the view model, * adding performance metrics data to the final result. * * Timing points are captured around the parsing and model building steps, * and this is added to the metrics which were returned from the `FetchResponse`. * * When using this method, it is the responsibility of the caller * to perform the network fetch in order to have a `FetchResponse` object. * The parsing logic which transforms the `FetchResponse` object into an intermediate model object * will need to be decoupled so that it can be implemented in the `parser` function. * * @param response - The response from a `Network.fetch()` call. * @param objectGraph - Object graph that can be used to pass data to the `parser` and `renderer` steps. * @param parser - A step that parses a `FetchResponse` to an intermediate model object. * @param modelBuilder - A step that takes the output of the `parser` step, and builds the view model. * This parameter supports both synchronous and asynchronous functions. * @returns The view model. */ async function parseAndBuildModel(response, objectGraph, parser, modelBuilder) { const modifiedObjectGraph = ensureFetchTimingMetricsBuilderExists(objectGraph, false); const fetchTimingMetricsBuilder = (0, dependencies_1.inject)(fetch_timing_metrics_builder_1.fetchTimingMetricsBuilderType, modifiedObjectGraph); // Add metrics from FetchResponse, and run the parser, capturing timing points. const parsedObject = fetchTimingMetricsBuilder.measureParsing(response, () => { return parser(response, modifiedObjectGraph); }); if ((0, optional_1.isNothing)(parsedObject)) { throw new Error("parser function returned null or undefined"); } return await constructAndDecorateModel(parsedObject, modifiedObjectGraph, modelBuilder); } exports.parseAndBuildModel = parseAndBuildModel; async function constructAndDecorateModel(parsedObject, objectGraph, modelBuilder) { const fetchTimingMetricsBuilder = (0, dependencies_1.inject)(fetch_timing_metrics_builder_1.fetchTimingMetricsBuilderType, objectGraph); // Run the model builder, capturing timing points. const model = await fetchTimingMetricsBuilder.measureModelConstructionAsync(async () => { const maybePromise = modelBuilder(parsedObject, objectGraph); // The actual model, or a Promise of the model. return await Promise.resolve(maybePromise); // If it was promise, it will await until the promise is resolved. }); if ((0, optional_1.isNothing)(model)) { throw new Error("model builder function returned null or undefined"); } // Decorate the final output with the metrics data. fetchTimingMetricsBuilder.decorate(model); return model; } //# sourceMappingURL=parse-and-build-model.js.map