@nestjs/microservices/deserializers/incoming-response.deserializer.js

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

/**
 * The only keys a Nest packet can carry. `status` is set by the
 * "no handler" packet emitted by RabbitMQ.
 */
const ENVELOPE_KEYS = new Set([
    'id',
    'err',
    'response',
    'isDisposed',
    'status',
]);
/**
 * @publicApi
 */
export class IncomingResponseDeserializer {
    deserialize(value, options) {
        return this.isExternal(value) ? this.mapToSchema(value) : value;
    }
    isExternal(value) {
        if (!value || typeof value !== 'object') {
            return true;
        }
        const keys = Object.keys(value);
        if (keys.length === 0) {
            return true;
        }
        // Nest packets never carry extra keys, unlike a foreign payload that
        // happens to contain `response` / `err` / `isDisposed`.
        return keys.some(key => !ENVELOPE_KEYS.has(key));
    }
    mapToSchema(value) {
        return {
            id: value && value.id,
            response: value,
            isDisposed: true,
        };
    }
}