我刚刚开始在我的Centos 7服务器上设置Flutter (Channel stable, 3.0.0)。我已经设置了代理配置，并将chrome添加为连接设备。我没有安装Android Studio，因为我不会在这个服务器上使用它。
使用命令
运行我的Flutter web应用程序时flutter run -d chrome
我得到以下错误:
Proxy failed to establish tunnel (407 Proxy Authentication Required)
---- Log transcript ----
FINE: Pub 2.17.0
MSG : Resolving dependencies...
SLVR: fact: rob_chatbot is 1.0.0+1
SLVR: derived: rob_chatbot
SLVR: fact: rob_chatbot depends on flutter from sdk
SLVR: fact: rob_chatbot depends on cupertino_icons ^1.0.2
SLVR: fact: rob_chatbot depends on flutter_test from sdk
SLVR: fact: rob_chatbot depends on flutter_lints ^1.0.0
SLVR: selecting rob_chatbot
SLVR: derived: flutter_lints ^1.0.0
SLVR: derived: flutter_test from sdk
SLVR: derived: cupertino_icons ^1.0.2
SLVR: derived: flutter from sdk
IO : Get versions from https://pub.dartlang.org/api/packages/flutter_lints.
IO : HTTP GET https://pub.dartlang.org/api/packages/flutter_lints
| Accept: application/vnd.pub.v2+json
| X-Pub-OS: linux
| X-Pub-Command: get
| X-Pub-Session-ID: 9143CA91-A5EC-4620-A2C9-817E982427C0
| X-Pub-Environment: flutter_bot:flutter_cli:verify:run
| X-Pub-Reason: dev
| user-agent: Dart pub 2.17.0
IO : Get versions from https://pub.dartlang.org/api/packages/lints.
IO : HTTP GET https://pub.dartlang.org/api/packages/lints
| Accept: application/vnd.pub.v2+json
| X-Pub-OS: linux
| X-Pub-Command: get
| X-Pub-Session-ID: 9143CA91-A5EC-4620-A2C9-817E982427C0
| X-Pub-Environment: flutter_bot:flutter_cli:verify:run
| user-agent: Dart pub 2.17.0
SLVR: Version solving took 0:00:00.160384 seconds.
| Tried 1 solutions.
FINE: Resolving dependencies finished (0.1s).
ERR : Proxy failed to establish tunnel (407 Proxy Authentication Required)
FINE: Exception type: ClientException
FINE: package:pub/src/source/hosted.dart 946:7 HostedSource._throwFriendlyError
| package:pub/src/source/hosted.dart 368:7 HostedSource._fetchVersionsNoPrefetching
| ===== asynchronous gap ===========================
| dart:async Future.catchError
| package:pub/src/utils.dart 109:52 captureErrors.wrappedCallback
| package:stack_trace Chain.capture
| package:pub/src/utils.dart 122:11 captureErrors
| package:pub/src/command.dart 183:13 PubCommand.run
| package:args/command_runner.dart 209:27 CommandRunner.runCommand
| package:pub/src/command_runner.dart 174:24 PubCommandRunner.runCommand
| package:pub/src/command_runner.dart 159:20 PubCommandRunner.run
| package:dartdev/dartdev.dart 45:56 runDartdev
| /b/s/w/ir/cache/builder/sdk/pkg/dartdev/bin/dartdev.dart 11:9 main
---- End log transcript ----
当我运行Flutter doctor -v时，我得到:
[✓] Flutter (Channel stable, 3.0.0, on CentOS Linux 7 (Core) 3.10.0-1160.59.1.el7.x86_64, locale en_PH.UTF-8)
• Flutter version 3.0.0 at /home/appadm/flutter
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision ee4e09cce0 (2 weeks ago), 2022-05-09 16:45:18 -0700
• Engine revision d1b9a6938a
• Dart version 2.17.0
• DevTools version 2.12.2
[✗] Android toolchain - develop for Android devices
✗ Unable to locate Android SDK.
Install Android Studio from: https://developer.android.com/studio/index.html
On first launch it will assist you in installing the Android SDK components.
(or visit https://flutter.dev/docs/get-started/install/linux#android-setup for detailed instructions).
If the Android SDK has been installed to a custom location, please use
`flutter config --android-sdk` to update to that location.
[✓] Chrome - develop for the web
• Chrome at google-chrome
[!] Linux toolchain - develop for Linux desktop
• clang version 3.4.2 (tags/RELEASE_34/dot2-final)
• cmake version 3.22.4
• ninja version 1.10.2
• pkg-config version 0.27.1
✗ pkg-config 0.29.0 or later is required.
[!] Android Studio (not installed)
• Android Studio not found; download from https://developer.android.com/studio/index.html
(or visit https://flutter.dev/docs/get-started/install/linux#android-setup for detailed instructions).
[✓] Proxy Configuration
• HTTP_PROXY is set
• NO_PROXY is localhost,127.0.0.1,::1,https://pub.dartlang.org
• NO_PROXY contains localhost
• NO_PROXY contains 127.0.0.1
• NO_PROXY contains ::1
[✓] Connected device (2 available)
• Linux (desktop) • linux • linux-x64 • CentOS Linux 7 (Core) 3.10.0-1160.59.1.el7.x86_64
• Chrome (web) • chrome • web-javascript • Google Chrome 101.0.4951.64
[!] HTTP Host Availability
✗ HTTP host "https://cocoapods.org/" is not reachable. Reason: An error occurred while checking the HTTP host: Proxy
failed to establish tunnel (407 Proxy Authentication Required)
✗ HTTP host "https://maven.google.com/" is not reachable. Reason: An error occurred while checking the HTTP host:
Proxy failed to establish tunnel (407 Proxy Authentication Required)
✗ HTTP host "https://pub.dev/" is not reachable. Reason: An error occurred while checking the HTTP host: Proxy
failed to establish tunnel (407 Proxy Authentication Required)
✗ HTTP host "https://cloud.google.com/" is not reachable. Reason: An error occurred while checking the HTTP host:
Proxy failed to establish tunnel (407 Proxy Authentication Required)
我已经找到了一个答案，说添加https://pub.dartlang.org/到我的代理规则，虽然我不知道在哪里找到。
您的代理密码是否包含url编码的符号，如'@' ?使用不包含符号的密码