Proxy connection failed

# the proxy this shell would use without being told
env | grep -i _proxy

# can this machine reach the gateway at all?
nc -vz resi.proxymonkey.io 8000
curl -sv -o /dev/null -x http://USER:[email protected]:8000 https://httpbin.org/ip 2>&1 | grep -iE 'trying|connected|failed'

# curl: (7) Failed to connect to ...    the failure Chrome reports as -130

import requests
from requests.utils import get_environ_proxies

URL = "https://httpbin.org/ip"
PROXY = "http://USER:[email protected]:8000"

print("proxies from the environment:", sorted(get_environ_proxies(URL)))

with requests.Session() as http:
    http.trust_env = False
    try:
        r = http.get(URL, proxies={"http": PROXY, "https": PROXY}, timeout=15)
        print("reached the proxy and the site:", r.status_code)
    except requests.exceptions.ProxyError as err:
        print("could not reach the proxy:", err)

import os
from urllib.parse import urlsplit

from scrapy.exceptions import CannotResolveHostError, DownloadConnectionRefusedError
from twisted.internet.error import ConnectError

async def start(self):
    self.logger.info("proxy variables set: %s", sorted(k for k in os.environ if k.lower().endswith("_proxy")))
    for url in self.start_urls:
        yield scrapy.Request(url, errback=self.on_error)

def on_error(self, failure):
    if failure.check(CannotResolveHostError, DownloadConnectionRefusedError, ConnectError):
        proxy = urlsplit(failure.request.meta.get("proxy") or "")
        self.logger.error("never reached the proxy at %s:%s: %r", proxy.hostname, proxy.port, failure.value)

from playwright.sync_api import Error, sync_playwright

PROXY = {"server": "http://resi.proxymonkey.io:8000", "username": "USER", "password": "PASS"}

with sync_playwright() as p:
    browser = p.chromium.launch(proxy=PROXY)
    page = browser.new_page()
    try:
        page.goto("https://httpbin.org/ip", timeout=20_000)
        print(page.inner_text("body"))
    except Error as err:
        if "ERR_PROXY_CONNECTION_FAILED" in err.message:
            print("Chromium never reached", PROXY["server"])
        else:
            raise
    browser.close()

# Firefox: NS_ERROR_PROXY_CONNECTION_REFUSED, or NS_ERROR_UNKNOWN_PROXY_HOST if the name does not resolve

import { fetch, ProxyAgent } from "undici";

const dispatcher = new ProxyAgent("http://USER:[email protected]:8000");

const codes = (err) => {
  const seen = [];
  for (let e = err; e; e = e.cause) if (e.code) seen.push(e.code);
  return seen;
};

try {
  await fetch("https://httpbin.org/ip", { dispatcher });
} catch (err) {
  console.error(codes(err).join(" <- ") || err.message);
}

// ECONNREFUSED   nothing is listening at that host and port
// ENOTFOUND      the proxy's hostname does not resolve