opt-cc/server/routes/ranks.js

'use strict';

// modules
const fs = require('fs');
const express = require('express');
const multer = require('multer');
const storage = multer.memoryStorage();
const upload = multer({storage: storage});

// HTTP status codes by name
const codes = require('./http-codes');

const apiAuthenticationMiddleware = require('../middleware/auth-middleware');
const checkHl = require('../middleware/permission-check').checkHl;

const routerHandling = require('../middleware/router-handling');
const idValidator = require('../middleware/validators').idValidator;
const resourceLocation = require('../middleware/resource-location').resourceLocation().concat('/rank/');

// Mongoose Model using mongoDB
const RankModel = require('../models/rank');

// util
const genericGetById = require('./_generic').genericGetById;
const getFileBuffer = require('../tools/util').getFileBuffer;
const imageDimensionValidator = require('../middleware/validators').imageDimensionValidator;
const MAX_IMAGE_WIDTH = 120;
const MAX_IMAGE_HEIGHT = 120;

const ranks = new express.Router();

// routes **********************
ranks.route('/')
     .get((req, res, next) => {
       const filter = {};
       if (req.query.fractFilter) {
         filter.fraction = req.query.fractFilter.toUpperCase();
       }
       if (req.query.q) {
         filter.name = {$regex: req.query.q, $options: 'i'};
       }

       RankModel.find(filter, {}, {sort: {fraction: 'asc', level: 'asc'}}, (err, items) => {
         if (err) {
           err.status = codes.servererror;
           return next(err);
         }

         if (items && items.length > 0) {
           res.locals.items = items;
         } else {
           res.locals.items = [];
         }
         res.locals.processed = true;
         next();
       });
     })

     .post(apiAuthenticationMiddleware, checkHl, upload.single('image'), (req, res, next) => {
       if (req.file) {
         const imageFileBuffer = getFileBuffer(req.file);
         const err = imageDimensionValidator(imageFileBuffer, MAX_IMAGE_WIDTH, MAX_IMAGE_HEIGHT);
         if (err) {
           return next(err);
         }

         const rank = new RankModel(req.body);
         // timestamp and default are set automatically by Mongoose Schema Validation
         rank.save((err) => {
           if (err) {
             err.status = codes.wrongrequest;
             next(err);
           }
           res.status(codes.created);
           res.locals.items = rank;
           fs.appendFile(resourceLocation + rank._id + '.png', imageFileBuffer,
             (err) => {
               next(err);
             });
         });
       } else {
         const err = new Error('no image file provided');
         err.status = codes.wrongmediasend;
         next(err);
       }
     })

     .all(
       routerHandling.httpMethodNotAllowed
     );


ranks.route('/:id')
     .get(idValidator, (req, res, next) => {
       return genericGetById(req, res, next, RankModel);
     })

     .patch(apiAuthenticationMiddleware, checkHl, upload.single('image'), (req, res, next) => {
       if (!req.body || (req.body._id && req.body._id !== req.params.id)) {
         // little bit different as in PUT. :id does not need to be in data, but if the _id and url id must match
         const err = new Error('id of PATCH resource and send JSON body are not equal ' + req.params.id + ' ' +
           req.body._id);
         err.status = codes.notfound;
         next(err);
         return; // prevent node to process this function further after next() has finished.
       }

       // optional task 3: increment version manually as we do not use .save(.)
       req.body.updatedAt = new Date();
       req.body.$inc = {__v: 1};

       if (req.file) {
         const imageFileBuffer = getFileBuffer(req.file);
         const err = imageDimensionValidator(imageFileBuffer, MAX_IMAGE_WIDTH, MAX_IMAGE_HEIGHT);
         if (err) {
           return next(err);
         }

         const file = resourceLocation + req.params.id + '.png';
         fs.unlink(file, (err) => {
           if (err) next(err);
           fs.appendFile(file, imageFileBuffer,
             (err) => {
               if (err) next(err);
             });
         });
       }

       // PATCH is easier with mongoose than PUT. You simply update by all data that comes from outside. no need to
       // reset attributes that are missing.
       RankModel.findByIdAndUpdate(req.params.id, req.body, {new: true}, (err, item) => {
         if (err) {
           err.status = codes.wrongrequest;
         } else if (!item) {
           err = new Error('item not found');
           err.status = codes.notfound;
         } else {
           res.locals.items = item;
         }
         next(err);
       });
     })

     .delete(apiAuthenticationMiddleware, checkHl, (req, res, next) => {
       RankModel.findByIdAndRemove(req.params.id, (err, item) => {
         if (err) {
           err.status = codes.wrongrequest;
         } else if (!item) {
           err = new Error('item not found');
           err.status = codes.notfound;
         }
         // we don't set res.locals.items  and thus it will send a 204 (no content) at the end. see last handler
         // user.use(..)
         res.locals.processed = true;
         next(err); // this works because err is in normal case undefined and that is the same as no parameter
       });
     })

     .all(
       routerHandling.httpMethodNotAllowed
     );


// this middleware function can be used, if you like or remove it
// it looks for object(s) in res.locals.items and if they exist, they are send to the client as json
ranks.use(routerHandling.emptyResponse);


module.exports = ranks;