@nestjs/microservices/client/client-proxy.js

Nest - modern, fast, powerful node.js web framework (@microservices)

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.ClientProxy = void 0;
const random_string_generator_util_1 = require("@nestjs/common/utils/random-string-generator.util");
const shared_utils_1 = require("@nestjs/common/utils/shared.utils");
const rxjs_1 = require("rxjs");
const operators_1 = require("rxjs/operators");
const incoming_response_deserializer_1 = require("../deserializers/incoming-response.deserializer");
const invalid_message_exception_1 = require("../errors/invalid-message.exception");
const identity_serializer_1 = require("../serializers/identity.serializer");
const utils_1 = require("../utils");
/**
 * @publicApi
 */
class ClientProxy {
    constructor() {
        this.routingMap = new Map();
        this._status$ = new rxjs_1.ReplaySubject(1);
    }
    /**
     * Returns an observable that emits status changes.
     */
    get status() {
        return this._status$.asObservable().pipe((0, operators_1.distinctUntilChanged)());
    }
    /**
     * Registers an event listener for the given event.
     * @param event Event name
     * @param callback Callback to be executed when the event is emitted
     */
    on(event, callback) {
        throw new Error('Method not implemented.');
    }
    /**
     * Send a message to the server/broker.
     * Used for message-driven communication style between microservices.
     * @param pattern Pattern to identify the message
     * @param data Data to be sent
     * @returns Observable with the result
     */
    send(pattern, data) {
        if ((0, shared_utils_1.isNil)(pattern) || (0, shared_utils_1.isNil)(data)) {
            return (0, rxjs_1.throwError)(() => new invalid_message_exception_1.InvalidMessageException());
        }
        return (0, rxjs_1.defer)(async () => this.connect()).pipe((0, operators_1.mergeMap)(() => new rxjs_1.Observable((observer) => {
            const callback = this.createObserver(observer);
            return this.publish({ pattern, data }, callback);
        })));
    }
    /**
     * Emits an event to the server/broker.
     * Used for event-driven communication style between microservices.
     * @param pattern Pattern to identify the event
     * @param data Data to be sent
     * @returns Observable that completes when the event is successfully emitted
     */
    emit(pattern, data) {
        if ((0, shared_utils_1.isNil)(pattern) || (0, shared_utils_1.isNil)(data)) {
            return (0, rxjs_1.throwError)(() => new invalid_message_exception_1.InvalidMessageException());
        }
        const source = (0, rxjs_1.defer)(async () => this.connect()).pipe((0, operators_1.mergeMap)(() => this.dispatchEvent({ pattern, data })));
        const connectableSource = (0, rxjs_1.connectable)(source, {
            connector: () => new rxjs_1.Subject(),
            resetOnDisconnect: false,
        });
        connectableSource.connect();
        return connectableSource;
    }
    createObserver(observer) {
        return ({ err, response, isDisposed }) => {
            if (err) {
                return observer.error(this.serializeError(err));
            }
            else if (response !== undefined && isDisposed) {
                observer.next(this.serializeResponse(response));
                return observer.complete();
            }
            else if (isDisposed) {
                return observer.complete();
            }
            observer.next(this.serializeResponse(response));
        };
    }
    serializeError(err) {
        return err;
    }
    serializeResponse(response) {
        return response;
    }
    assignPacketId(packet) {
        const id = (0, random_string_generator_util_1.randomStringGenerator)();
        return Object.assign(packet, { id });
    }
    connect$(instance, errorEvent = 'error', connectEvent = 'connect') {
        const error$ = (0, rxjs_1.fromEvent)(instance, errorEvent).pipe((0, operators_1.map)((err) => {
            throw err;
        }));
        const connect$ = (0, rxjs_1.fromEvent)(instance, connectEvent);
        return (0, rxjs_1.merge)(error$, connect$).pipe((0, operators_1.take)(1));
    }
    getOptionsProp(obj, prop, defaultValue = undefined) {
        return obj && prop in obj ? obj[prop] : defaultValue;
    }
    normalizePattern(pattern) {
        return (0, utils_1.transformPatternToRoute)(pattern);
    }
    initializeSerializer(options) {
        this.serializer =
            (options &&
                options.serializer) ||
                new identity_serializer_1.IdentitySerializer();
    }
    initializeDeserializer(options) {
        this.deserializer =
            (options &&
                options.deserializer) ||
                new incoming_response_deserializer_1.IncomingResponseDeserializer();
    }
}
exports.ClientProxy = ClientProxy;