performance problem, cors-anywhere doesn't use outbound HTTP keep-alive

In evaluating the performance of this nodeJS package, vs rewriting in Cloudflare Workers/Deno Deploy or Deno/Bun/perl/C if Im desperate. Cloudflare workers as a CORS proxy is unusable for my very unique use case, my target content origin is also CF based, its webmaster decided to block CF's IPs.

I noticed CORS-A inherits a performance degradation from https://github.com/http-party/node-http-proxy . node-http-proxy does NOT implement keep-alive, therefore cors-anywhere doesn't either. All outbound connections to a content server, are "Connection: close". That means HTTPS TLS negotiation every single time for all requests. I mean, its 1-2 ms ping, on a same city DC to DC fiber link, but those extra 3-6ms will add up and add up, if a UA page load has 2-5 CORS proxy requests before drawing content to eyeball.

CORS-A and node-http-proxy are starting to show their age. Lack of H2 and H2C (most cloud providers now offer H2 clear, from their edge proxy, TLS-removed, to your process) incoming, and no HTTP/S 1.1 keep-alive, and no H2 outbound.

PS. OT JSONP support would be nice, for some ancient Win2K embedded "adtech" screens I have, but I switch to a cloudflare worker for that and efficiency reasons, (99% of content servers doesn't block CF IPs), plus JSONP and IE 5, maybe IE 6, have performance problems, doing a 2nd string eval() on 800KB-1.4MB of JS-code (really JSON) on P2/P3 machines. So I break the typical convention of JSONP proxies returning {"status": 200; "content-type": "application/json"; "content": "{\"foo\":true}"} and just inline the content server JSON into JSONP, mild security problems if content server is NOT TRUSTED and returns malicious/malformed JSON, to avoid 2 rounds through the JS parser in ancient IE.

fetch("https://cors-anywhere.herokuapp.com/http://scooterlabs.com/echo")

Simple webservice echo test: make a request to this endpoint to return the HTTP request parameters and headers. Results available in plain text, JSON, or XML formats. See http://www.cantoni.org/2012/01/08/simple-webservice-echo-test for more details, or https://github.com/bcantoni/echotest for source code.

Array
(
    [method] => GET
    [headers] => Array
        (
            [Host] => scooterlabs.com
            [Connection] => close
            [Sec-Ch-Ua] => "(Not(A:Brand";v="8", "Chromium";v="98"
            [Sec-Ch-Ua-Mobile] => ?0
            [User-Agent] => Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.0.0 Safari/537.36
            [Sec-Ch-Ua-Platform] => "Windows"
            [Accept] => */*
            [Origin] => https://example.org
            [Sec-Fetch-Site] => cross-site
            [Sec-Fetch-Mode] => cors
            [Sec-Fetch-Dest] => empty
            [Referer] => https://example.org/
            [Accept-Encoding] => gzip, deflate, br
            [Accept-Language] => en-US,en;q=0.9
            [X-Forwarded-For] => 72.229.170.XXX
            [X-Forwarded-Proto] => https
            [X-Forwarded-Port] => 443
        )

    [request] => Array
        (
        )

    [client_ip] => 72.229.170.XXX
    [time_utc] => 2023-06-16T23:24:10+0000
    [info] => Echo service from Scooterlabs (http://www.scooterlabs.com)
)

Rob--W / cors-anywhere

performance problem, cors-anywhere doesn't use outbound HTTP keep-alive #464