@enter-at/lambda-handlers/handler/APIGatewayProxyHandler.js

An opinionated Typescript package that facilitates specifying AWS Lambda handlers including input validation, error handling and response formatting.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.APIGatewayProxyHandler = void 0;
const error_1 = require("../error");
const header_1 = require("../header");
const response_1 = require("../response");
const BaseHandler_1 = require("./BaseHandler");
const index_1 = require("../index");
class APIGatewayProxyHandler extends BaseHandler_1.BaseHandler {
    static handleError(err) {
        if (err instanceof error_1.ForbiddenError) {
            return (0, response_1.forbidden)(err.details);
        }
        if (err instanceof error_1.UnauthorizedError) {
            return (0, response_1.unauthorized)(err.details);
        }
        if (err instanceof error_1.BadRequestError || err instanceof error_1.FormatError || err instanceof error_1.ValidationError) {
            return (0, response_1.badRequest)(err.details);
        }
        if (err instanceof error_1.RequestTimeoutError) {
            return (0, response_1.requestTimeout)(err.details);
        }
        if (err instanceof error_1.UnprocessableEntityError) {
            return (0, response_1.unprocessableEntity)(err.details);
        }
        if (err instanceof error_1.NotFoundError) {
            return (0, response_1.notFound)(err.details);
        }
        if (err instanceof error_1.ConflictError) {
            return (0, response_1.conflict)(err.details);
        }
        index_1.config.logger.error({
            name: err.name,
            message: err.message,
            stack: err.stack,
        });
        return (0, response_1.internalServerError)();
    }
    corsHeader;
    constructor(args) {
        super(args);
        this.corsHeader = args?.cors ?? new header_1.CORSHeader("*", true);
    }
    after(result) {
        result = result ?? (0, response_1.noContent)();
        if (result.statusCode === undefined) {
            result = (0, response_1.ok)(result);
        }
        return this.createResponse(result);
    }
    onException(exception) {
        return this.createResponse(APIGatewayProxyHandler.handleError(exception));
    }
    formatInput(event) {
        if (!event.body) {
            return event;
        }
        try {
            event.body = this.inputFormat.apply(event.body);
            return event;
        }
        catch (err) {
            throw err;
        }
    }
    formatOutput(result) {
        const { body, ...properties } = result;
        return {
            body: body ? this.outputFormat.apply(body) : "",
            ...properties,
        };
    }
    createResponse(result) {
        result.headers = this.createHeaders(result.headers);
        return this.formatOutput(result);
    }
    createHeaders(headers) {
        return {
            ...headers,
            ...(this.corsHeader && this.corsHeader.create()),
            ...(this.outputFormat && new header_1.ContentTypeHeader(this.outputFormat.contentType).create()),
        };
    }
}
exports.APIGatewayProxyHandler = APIGatewayProxyHandler;