Files
J Logan 2443a245cb Fixes proxy logic in RegistryClient. (#314)
- Closes #255.
- Fixes ProxyUtils so that the environment variable to be used for proxy
selection is determined by the request scheme.
- RegistryClient uses ProxyUtils to get the proxy URL used by the
HTTPClient.
- Tweak hostname resolution error message to avoid misleading output if
the proxy hostname cannot be resolved.
2025-10-09 10:30:49 -04:00

74 lines
2.9 KiB
Swift

//===----------------------------------------------------------------------===//
// Copyright © 2025 Apple Inc. and the Containerization project authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//===----------------------------------------------------------------------===//
import ContainerizationError
import Foundation
/// A small utility to resolve proxy settings (HTTP(S)_PROXY / NO_PROXY).
public enum ProxyUtils {
/// Resolves the proxy URL for a given host based on environment variables.
/// Malformed http_proxy or https_proxy URLs are ignored.
/// Uses Go-style handling rules:
/// - Uppercase environment variables take priority over lowercase counterparts.
/// - Leading dot on no_proxy component implies prefix matching.
///
/// - Parameters:
/// - scheme: The request scheme.
/// - host: The request hostname.
/// - env: Environment variables to check, dafaulting to the process environment.
///
/// - Returns: The proxy URL to use, or `nil` for transparent connection.
public static func proxyFromEnvironment(
scheme: String?,
host: String,
env: [String: String] = ProcessInfo.processInfo.environment
) -> URL? {
guard let scheme else {
return nil
}
let httpProxy = env["HTTP_PROXY"] ?? env["http_proxy"]
let httpsProxy = env["HTTPS_PROXY"] ?? env["https_proxy"]
let noProxy = env["NO_PROXY"] ?? env["no_proxy"]
// If NO_PROXY matches → skip proxy
if let noProxy, shouldBypassProxy(host: host, noProxy: noProxy) {
return nil
}
// Select proxy based on scheme, defaulting to http.
let proxy = scheme == "https" ? httpsProxy : httpProxy
guard let proxy, let proxyUrl = URL(string: proxy) else {
return nil
}
return proxyUrl
}
/// Check if a host should bypass proxy according to NO_PROXY.
/// - Example: NO_PROXY=".example.com,localhost,127.0.0.1"
private static func shouldBypassProxy(host: String, noProxy: String) -> Bool {
let entries = noProxy.split(separator: ",").map { $0.trimmingCharacters(in: .whitespaces) }
for entry in entries {
if entry.isEmpty { continue }
if entry == "*" { return true }
if host == entry { return true }
if entry.hasPrefix(".") && host.hasSuffix(entry) { return true }
}
return false
}
}