weather_map-server

Detroit Labs coding challenge - simple weather forecast application - Backend Node.js server

This is a Node.js backend server to provide API to be used with weather forecast application altoinu/weather_map-client.

Writing README stuff

https://help.github.com/en/articles/basic-writing-and-formatting-syntax

Node stuff

• Node.js (v23.5.0) and npm https://nodejs.org/
• PM2 (v5.4.3) http://pm2.keymetrics.io

Initial set up

npm install

Environment variables

Set following values via .env

# Array of origins to allow in CORS, JSON format
CORS_ALLOW_ORIGIN=["http://localhost", "http://localhost:3000"]
# Port number to listen to.
PORT=4000
# API key obtained from Open Weather Map
OPEN_WEATHER_MAP_API_KEY=XXXXXX

To run (for development)

npm run dev

...then try accessing one of defined routes:

• http://localhost:4000/getip.json
• http://localhost:4000/config.json

To start/restart with PM2:

pm2 start [ecosystem config file].js
pm2 restart [ecosystem config file].js
pm2 startOrRestart [ecosystem config file].js

• PM2 cluster mode
• Immediately shuts down currently running process and then starts new one.
  • Causes this too-
    • App [app_name] with id [0] and pid [20743], exited with code [100] via signal [SIGINT]

To reload:

pm2 reload [ecosystem config file].js
pm2 startOrReload [ecosystem config file].js

• PM2 cluster mode, reload
• https://stackoverflow.com/questions/44883269/what-is-the-difference-between-pm2-restart-and-pm2-reload
  • "With reload, pm2 restarts all processes one by one, always keeping at least one process running."
  • "If the reload system hasn’t managed to reload your application, a timeout will fallback to a classic restart."

To gracefully reload (RECOMMENDED):

pm2 gracefulReload [ecosystem config file].js
pm2 startOrGracefulReload [ecosystem config file].js (reloads env var as well)

• PM2 cluster mode, graceful shutdown
• http://pm2.keymetrics.io/docs/usage/signals-clean-restart/
  • Allows to do process.on('SIGINT', function() {... before shutdown

Notes when restarting:

As of pm2 -v 3.5.1

• --update-env option doesn't seem to be working as it should
  • Unitech/pm2#3796
• watch: true does not update env that were changed in config .js/json
  • need to manually do pm2 startOrGracefulReload [ecosystem config file].js
• Manual restart/reload/gracefulReload causes env to be updated to whatever is in config .js/json
  • However if env var is removed from .js/json, it still remains in process.env and gets loaded. Not sure if this is pm2/node bug or just the way things are. - To prevent this, do pm2 delete to completely remove then pm2 start

Lint

npm run lint:fix

Generating docs

npm run build:doc

• Runs both apidoc and jsdoc

apidoc

npm run build:doc:apidoc

• outputs to docs/apidoc
• https://www.npmjs.com/package/apidoc
• http://apidocjs.com/
  • params

jsdoc

npm run build:doc:jsdoc

• outputs to docs/jsdoc
• https://www.npmjs.com/package/jsdoc
• https://jsdoc.app/
  • Getting started
  • tags
  • Namepaths
  • Namespace
    • memberof
  • Module
    • param
    • Function
    • Class