app2-api/core/controllers/index.js

const _find = require('./find');
const httpStatus = require('http-status');
const { extractParamsFromRequest, handleErrorResponse, handleResultResponse } = require('../../helpers/controller.helper');

function buildContext(req, config ) {
    return {
        user: req.user,
        scopes: [],
        ...config,
    }
}

const defaultOptions = {
    MODULE_NAME: 'default',
    params: {
        find: { includeAll: false },
        findOne: { includeAll: false, paginate: { limit: 1, page: 1 } },
        count: {},
        create: {},
        update: {},
        delete: {},
    }
}

const generateControllers = (service, extraControllers = {}, options = {}) => {
    const _options = {
        ...defaultOptions,
        ...options
    };

    const defaultControllers = {

        find: (config) => {

            return async (req, res, next) => {
                config = config || {
                    scopes: [],
                };

                const params = extractParamsFromRequest(req, res, _options.params.find);
                try {
                    const result = await service.fetchAll(params, buildContext(req, config));
                    return handleResultResponse(result.rows, result.count, params, res);
                } catch (error) {
                    return handleErrorResponse(_options.MODULE_NAME, 'find', error, res)
                }
            }
        },

        findOne: (config) => {
            return async (req, res, next) => {
                const params = extractParamsFromRequest(req, res, _options.params.findOne);
                try {
                    const result = await service.fetchOne(params, buildContext(req, config));
                    return handleResultResponse(result, null, params, res, (result === null) ? httpStatus.NOT_FOUND : httpStatus.OK);
                } catch (error) {
                    console.log(error);
                    return handleErrorResponse(_options.MODULE_NAME, 'findOne', error, res)
                }
            }
        },

        count: (config) => {
            return async(req, res, next) => {
                const params = extractParamsFromRequest(req, res, _options.params.count);
                try {
                    const result = await service.count(params, buildContext(req, config));
                    return handleResultResponse(result, null, params, res);
                } catch (error) {
                    return handleErrorResponse(_options.MODULE_NAME, 'count', error, res)
                }
            }
        },

        create: (config) => {
            return async (req, res, next) => {
                try {
                    const result = await service.create(req.body, buildContext(req, config));                
                    return handleResultResponse(result, null, null, res, httpStatus.CREATED)
                } catch (error) {
                    return handleErrorResponse(_options.MODULE_NAME, 'create', error, res)
                }
            }
        },

        update: (config) => {
            return async (req, res, next) => {
                try {                    
                    const params = extractParamsFromRequest(req, res, _options.params.update);
                    const response = await service.update(params, req.body, buildContext(req, config));
                    // https://sequelize.org/master/class/lib/model.js~Model.html#static-method-update
                    // Update devuelve un array de un elemento con el número de filas afectadas
                    // por la operación. Por comodidad, devuelvo el valor, no el array.
                    
                    let result = response[0];
                    let status = httpStatus.OK;
                    if (result < 1) {
                        status = httpStatus.NOT_FOUND;
                    }

                    // Express no puede devolver números porque los confunde con el 'status'.
                    // Convertimos a cadena.
                    result = result.toString();

                    return handleResultResponse(result, null, req.params, res, status)
                } catch (error) {
                    return handleErrorResponse(_options.MODULE_NAME, 'update', error, res)
                }
            }
        },

        delete: (config) => {
            return async (req, res, next) => {
                try {
                    const result = await service.delete(req.params, buildContext(req, config));
                    return handleResultResponse(result, null, req.params, res, httpStatus.NO_CONTENT);
                } catch (error) {
                    return handleErrorResponse(_options.MODULE_NAME, 'delete', error, res)
                }
            }
        },
    }

    //const associationControllers = generateAssociationControllers(model, options);

    //console.log(associationControllers);

    return {
        ...defaultControllers,
        //...associationControllers
        ...extraControllers
    }
}


module.exports = generateControllers;
module.exports.buildContext = buildContext;