node-get-url-proxy

get-url-proxy will return the applicable proxy to use for a given URL based on NO_PROXY and {PROTOCOL}_PROXY environment variables.

console.log(process.env.HTTP_PROXY) // "http://proxy:8080/"
console.log(process.env.NO_PROXY); // ".foo.com,192.168.1."

// requires protocol & domain
var getProxy = require('get-url-proxy');
getProxy('http://foo.com/'); // null
noProxy('https://www.google.com/'); // "http://proxy:8080/"

// the cached wrapper will cache the last 100 resources
var cachedProxy = require('get-url-proxy/cached');

// protocol only, without NO_PROXY check
var protocolProxy = require('get-url-proxy/protocol');
protocolProxy('https'): // "http://proxy:8080/"

Search Order

The following search order will be used, generally speaking...

• NO_PROXY exclusion will return null
• PROTOCOL_PROXY
• protocol_proxy
• ALL_PROXY
• all_proxy
• null will be returned with no match.

Web protocols

For web based protocols, additional/similar protocols will be searched as a fallback.

• HTTP -> [HTTP, HTTPS]
• HTTPS -> [HTTPS, HTTP]
• WS -> [WS, WSS, HTTPS, HTTP]
• WSS -> [WSS, WS, HTTPS, HTTP]
• SFTP -> [SFTP, SSH]

All other protocols will only search for their own protocol specifically, falling back to ALL_PROXY

NOTE: You may want to use memoization around this module.

WARNING

If you are using a node version prior to Node 8, you should install url-parse as a dependency.