simple-cors

why

This small script was originally designed to be used with AWS ALBs as a reverse proxy to support CORS. It is meant to have the ALB target a small ecs task running it. When targeting this task the origin specified by the ALB is the target that is proxied.

features:

• supports preflight requests
• redirects same origins

Ex.

client request to https://subdomain.app.com
-> alb listener on 443 (ssl termination)
-> alb rule to target proxy on ecs
-> proxy sends request to http://subdomain.app.com:442
-> alb listener on 442
-> alb rule to target app on ecs
-> proxy returns response with matching CORS headers
-> client

env options

• PROXY_AS_HTTPS
  • set to "1" to enable https in the proxy target
• ALLOWED_ORIGIN_ROOT
  • set to the root of the origin that is allowed
  • ex. google.com to allow anything.google.com
• PORT
  • port to server the proxy server, a health check is served on the port + 1,
  • defaults to 80 (health check on 81)
• ENABLE_LOGGING
  • set to 0 to disable logging
  • enabled by default
• PROXIED_PORT
  • port to proxy requests to
  • by default it will be set to the matching port for the protocol
• DISABLE_REPROXY
  • disable reproxy attempts
• ENABLE_REDIRECT
  • enable redirecting on same origin or no origin
• PER_DOMAIN
  • configure per domain settings as
    • old_domain@protocol:new_domain:port
    • where protocol is http or https
    • protocol and/or port may be omitted to use defaults

health check

A health check is served on http://server:PORT+1/

commands

• npm build -> to build into dist folder
• npm run debug -> to run server for testing
• npm run serve -> to run production