清华
FLUTTER_STORAGE_BASE_URL=https://mirrors.tuna.tsinghua.edu.cn/flutter
PUB_HOSTED_URL=https://mirrors.tuna.tsinghua.edu.cn/dart-pub
上海交大
PUB_HOSTED_URL=https://dart-pub.mirrors.sjtug.sjtu.edu.cn
FLUTTER_STORAGE_BASE_URL=https://mirrors.sjtug.sjtu.edu.cn
CNNIC
PUB_HOSTED_URL=http://mirrors.cnnic.cn/dart-pub
FLUTTER_STORAGE_BASE_URL=http://mirrors.cnnic.cn/flutter
腾讯
PUB_HOSTED_URL=https://mirrors.cloud.tencent.com/dart-pub
FLUTTER_STORAGE_BASE_URL=https://mirrors.cloud.tencent.com/flutter
Flutter中文站
export PUB_HOSTED_URL=https://pub.flutter-io.cn
export FLUTTER_STORAGE_BASE_URL=https://storage.flutter-io.cn