feat: Add local proxy support for translation requests

[acefeng]

feat: Add local proxy support for translation requests

Summary

Adds a Local Proxy configuration option under Settings → Advanced, allowing users to route all translation service requests through a custom HTTP or SOCKS5 proxy. This eliminates the need to configure system-wide proxy or third-party tools just to make individual translation services reachable.

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Motivation

This feature has been requested multiple times across several issues:

• 能否为软件加入内置代理 #557 — 能否为软件加入内置代理: Users want a built-in proxy option so they don't need to enable a system-wide proxy just for Easydict.
• 希望增加https和socks代理设置。 #688 — 希望增加 https 和 socks 代理设置: Request for per-app HTTP/SOCKS proxy instead of relying on global system proxy.
• 🚀 功能建议：能否支持自定义proxy设置 #756 — 能否支持自定义 proxy 设置: Users report translation services (e.g. Google Translate) timing out when not using global proxy mode.
• 功能建议：配置代理功能 #18 — 功能建议：配置代理功能: Original feature request going back to 2023 — users running Clash/V2Ray in rule mode (not global mode) can't easily have Easydict route through the proxy.

The common scenario: many users run proxy software in rule-based or browser-only mode and don't enable a system-wide proxy. Without this feature, translation services that require a proxy would time out, forcing users to switch to global mode just for Easydict.

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What's Changed

New UI — Settings → Advanced → Local Proxy

A new Local Proxy section is added below the existing HTTP Server section in the Advanced settings tab. Users can input a proxy URL; leaving it empty disables the proxy and falls back to system default networking.

![screenshot placeholder]

Supported proxy formats:

• http://host:port — HTTP proxy (also tunnels HTTPS via CONNECT)
• socks5://host:port — SOCKS5 proxy
• host:port — treated as HTTP proxy

Key implementation details:

• NetworkSession.swift (new): A final class NetworkSession singleton manages the app-wide Alamofire Session. It observes Defaults[.httpProxyURL] via Defaults.publisher and rebuilds the session immediately whenever the value changes — no app restart required.
• A global computed variable EAF: Alamofire.Session is exposed at file scope, providing a drop-in replacement for Alamofire's built-in AF.
• All 15 translation service files (GoogleService, BingService, DeepLService, BaiduService, YoudaoService, TencentService, CaiyunService, VolcanoService, AliService, NiuTransService, OllamaService, etc.) have been updated to use EAF instead of AF, so every request automatically respects the proxy setting.
• A new Defaults.Keys.httpProxyURL key (default: empty string) is added to Defaults.Keys+Extension.swift.
• Localization keys added for all supported languages (English, Simplified Chinese, Traditional Chinese, Slovak).

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Files Changed

File	Change
NetworkSession.swift	New — proxy-aware session manager + global EAF accessor
Defaults.Keys+Extension.swift	Added httpProxyURL key
AdvancedTab.swift	Added Local Proxy section + @Default(.httpProxyURL)
Localizable.xcstrings	Added 4 new localization keys
project.pbxproj	Registered NetworkSession.swift
15 translation service files	AF → EAF

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Testing

1. Enter a non-existent local proxy (e.g. http://127.0.0.1:19999) → translation requests should fail with a connection error, confirming requests go through the proxy.
2. Clear the field → requests recover immediately, confirming fallback to system default.
3. Enter a valid local proxy port (e.g. http://127.0.0.1:7890 for Clash) with system proxy disabled → translation services that previously timed out should now work.

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Closes #557
Related: #18, #688, #756

[github-actions]

Hello acefeng, Thank you for your first PR contribution 🎉 acefeng

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

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[MoonMao42]

On Easydict/Swift/Service/OpenAI/BaseOpenAIService.swift:78:

OpenAI(apiToken:) uses URLSession.shared, so NetworkSession.shared.urlSession never reaches this path.

        let openAI = OpenAI(
            configuration: .init(token: apiKey),
            session: NetworkSession.shared.urlSession
        )

Does this work?

[acefeng]

On Easydict/Swift/Service/OpenAI/BaseOpenAIService.swift:78:

OpenAI(apiToken:) uses URLSession.shared, so NetworkSession.shared.urlSession never reaches this path.

        let openAI = OpenAI(
            configuration: .init(token: apiKey),
            session: NetworkSession.shared.urlSession
        )

Does this work?

Perhaps I should modify the description. open AI and gemini AI are not supported for the time being. open AI needs to modify the injection method, but for gemini AI, no injection method has been seen for the time being, so neither of them has been done for the time being