My notes on course Getting Started with Express.js. Branches approximately follows lessons.
>git checkout 00-empty-repo
Run express on node:
>npm init -y \\init empty node project, default settings
>npm i -S express \\add express module
>npm i -D nodeman \\add module nodemon to node dev dependecies
>npn start \\run start script see package.json>scripts>start
>npm run dev \\run dev scripts see package.json>scripts>dev
Register handler to HTTP GET method: app.get(path, callback).
Callback function parameters are: req, res.
>git checkout 01-express-run
>npm i -S lodash \\add lodash modules (utility library)
>node helper_create_users.js \\run js script for create users.json
Callback functions params: req, res, next. Call next registered handler within matched path by next(). Registered handlers are called in same order as been declared.
>git checkout 02-express-route
Install template engines: Handlebars and pug(Jade):
>npm i -S pug
>npm i -S hbs
Add view directory: app.set('views', './views')
Add view template engine: app.set('view engine', engine). View engine such as hbs or pug.
Render template call on res object: res.render('path', context)
>git checkout 03-express-template
Set up serving static content by app.use([path,] callback).
Serves static files from 'images' directory within path 'profilepic': app.use('profilepic', express.static('images')).
>git checkout 04-express-staticfiles
Body-parser middleware parses request params to req.body, install: >npm i -S body-parser.
Use other HTML methods:
app.deleteapp.put
>git checkout 05-express-http
Validate inputs by middleware method: app.get(path, middleware, callback).
Log request by middleware: app.all(path, callback) via call next callback.
Other response methods:
res.download(file, [fileName])send file bytes as fileNameres.json(object)send object as json
>git checkout 06-express-routing-advanced
Chain handlers with same path by app.route(path).handler1().handler2()...
Separate router handlers with same path through:
var router = express.Router({
mergeParams: true
})
>git checkout 07-express-routing-refactored
Copy file with piping streams: fs.createReadStream(src).pipe(fs.createWriteStream(dst));
JSONStream streaming JSON.parse and JSON.stringify methods, isntall >npm i -S JSONStream.
>git checkout 08-express-streams
App handler middleware:
app.use(function(req, res, next) {
console.log(new Date(), req.method, req.path, req.params);
next()
})
Error handler middleware:
app.use(function(err, req, res, next){
console.error(err.stack)
res.status(500).send('Something broke')
})
>git checkout 09-express-middleware
Install and run mongodb in local directory:
>npm i -S mongodb
>mkdir mongod
>mongod --dbpath mongo
>mongoimport --db test --dbpath mongo --collection users --drop --file users_list.json
Mongoose = mongodb object modeling for nodejs: >npm i -S mongoose
Mongoose schema maps MongoDb collection and defines the shape of its documents to objects.
Statement console.error.bind(console, 'connection error:') create reference to console.error function called within console context and pass first argument.
Mongo basic operations:
find(query)findOne(query)findAndModify(query)
>git checkout 10-express-mongodb
Virtual properties are defined by getters and setters on mongoose schema.
>git checkout 11-express-mongoose-virtualprops
>git checkout 12-refactor-es6
Debug stand alone js file >node-debug helper_create_users.js.
Debug nodemon: >npm run debug and run in separate console >node-inspector.
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