faustineinsun / scalaJS-playground

A Node.js web app on Heroku

scalaJS-playground

• http://www.scala-js-fiddle.com/
• http://lihaoyi.github.io/hands-on-scala-js/
• http://www.scala-js.org/doc/tutorial.html

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Local

Run on local

• $ foreman start web
• http://localhost:5000/

Scala.js

$ sbt
> // set scalaJSStage in Global := FastOptStage // has been set in `local.sbt`, run code with Node.js
> run
> last
> reload // reload the build file if sbt is still running
> fastOptJS
> ~fastOptJS   // `~` means automatically refreshing the page when recompilation is complete
> fullOptJS // takes tens of seconds, but can compress the compiled code

Scala Tools

• scalatags
• upickle
• scalaz
• shapeless

Node Modules

• template engine
  • gaikan the fastest
  • Jade
• Bootstrap layoutit
  • Bootstrap Components

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Heroku

Scalability

Procfile can set background worker process
$ heroku ps  --> check how many dynos are running
$ heroku ps:scale web=2 --> can reduce delay but it's expensive

Run on local and remote machines

$ npm install
$ foreman start web --> run app locally, use `curl` to test
git commit and push
$ git push origin master --> push to Github Master branch
$ git push heroku master --> push to Heroku
$ heroku open --> run on heroku
$ heroku restart --> solve Application Error

Modify environment variable

local (Foreman)
$ bin/loadEnv4Foreman.sh --> load `.env` from backup dir (Foreman needs `.env`)  
$ vim .env
echo .env >> .gitignore  --> sensitive configuration values should not be committed to source-control
$ foreman start

remote (Heroku)
$ heroku config:set TIMES=2
$ heroku config
$ bin/beforeCommit.sh --> backup and delete .env in current folder
git commit and push
$ heroku open

ClearDB MySQL

$ heroku addons:add cleardb:ignite
$ heroku config
$ heroku config:add DATABASE_URL=(the_copied_value_of_CLEARDB_DATABASE_URL)
$ heroku config -s | grep CLEARDB_DATABASE_URL >> .env
$ more .env
$ echo .env >> .gitignore --> sensitive configuration values should not be committed to source-control
$ bin/beforeCommit.sh --> backup `.env`

• Setup Heroku MySQL credentials on node.js
  • install mysql on node.js $ npm install
  • credential info are saved to .env and heroku config:set
  • add new connection on local MySQL with Heroku MySQL credentials -> create table, insert a record to mysql on local machine
  • modify index.js and package.json

Memcached Cloud

$ heroku addons:add memcachedcloud:25
$ heroku config
set Memcached Cloud credentials both through `.env` and `heroku config:set`

• https://www.npmjs.com/package/memjs

  • include memjs into package.json, and then $ npm install

• node-memcached

Console

$ heroku run node
$ heroku run bash

AddOn + logs

$ heroku logs --tail
$ heroku addons:add papertrail --> logging add-on
$ heroku addons:open papertrail
$ heroku addons:docs papertrail
$ heroku addons

Neo4j Graph Database

localhost:7474

local 
$ brew install neo4j
$ neo4j start

philippkueng/node-neo4j: Neo4j REST API wrapper for Node.js

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Spray

• http://spray.io/
• https://github.com/wandoulabs/spray-socketio
• http://ibruce.info/2014/04/06/hello-spray/