无法从CPAN安装模块：‘could not find release’错误求助

通过代理访问外网环境，执行cpanm -v App::cpanminus时持续提示找不到App::cpanminus模块，但该模块实际存在于CPAN。已尝试多日仍无法解决，以下是相关操作日志及配置信息，恳请提供排查建议：

操作日志与配置信息 #

# export HTTP_PROXY="http://proxy.mycompany.com:8080"
[root@vm]# cpanm -v App::cpanminus
cpanm (App::cpanminus) 1.7047 on perl 5.026003 built for x86_64-linux-thread-multi
Work directory is /root/.cpanm/work/1728941689.1094777
You have make /usr/bin/make
You have LWP 6.72
You have /usr/bin/tar: tar (GNU tar) 1.30
Copyright (C) 2017 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by John Gilmore and Jay Fenlason.
You have /usr/bin/unzip
Searching App::cpanminus () on cpanmetadb ...
! Finding App::cpanminus on cpanmetadb failed.
! Could not find a release matching App::cpanminus on MetaCPAN.
Searching App::cpanminus on mirror http://www.cpan.org ...
Downloading index file http://www.cpan.org/modules/02packages.details.txt.gz ...
! Finding App::cpanminus () on mirror http://www.cpan.org failed.
! Couldn't find module or a distribution App::cpanminus
Expiring 1 work directories.

cpan[3]> o conf /proxy/
$CPAN::Config options from /root/.cpan/CPAN/MyConfig.pm:

ftp_proxy          [http://proxy-uat.mycompnay.com:8080]
http_proxy         [http://proxy-uat.mycompnay.com:8080]
no_proxy           []
proxy_pass         undef
proxy_user         []



# wget -e use_proxy=yes -e http_proxy=http://proxy.mycompany.com:8080 https://cpan.metacpan.org/authors/id/M/MI/MIYAGAWA/App-cpanminus-1.7047.tar.gz
--2024-10-14 21:39:50--  https://cpan.metacpan.org/authors/id/M/MI/MIYAGAWA/App-cpanminus-1.7047.tar.gz
Resolving proxy-uat.mycompany.com (proxy-uat.mycompany.com)... 10.202.192.1, 10.202.192.32
Connecting to proxy-uat.mycompany.com (proxy-uat.mycompany.com)|10.202.192.1|:8080... connected.
Proxy request sent, awaiting response... 200 OK
Length: 316779 (309K) [application/x-gzip]
Saving to: ‘App-cpanminus-1.7047.tar.gz

App-cpanminus-1.704 100%[===================>] 309.35K  --.-KB/s    in 0.03s   

2024-10-14 21:39:50 (11.6 MB/s) - ‘App-cpanminus-1.7047.tar.gz’ saved [316779/316779]

[root@vm]# ls -l App-cpanminus-1.7047.tar.gz 
-rw------- 1 root root 316779 Jul 30  2023 App-cpanminus-1.7047.tar.gz

# cat ~/.wgetrc 
use_proxy=yes
http_proxy=http://proxy-uat.mycompany.com:8080
https_proxy=http://proxy-uat.mycompany.com:8080
ftp_proxy=http://proxy-uat.mycompany.com:8080

排查建议 #

• 统一代理配置：
  当前设置的HTTP_PROXY环境变量是proxy.mycompany.com:8080，但CPAN配置文件和.wgetrc中使用的是proxy-uat.mycompany.com:8080，域名不一致可能导致cpanm无法正确走代理。建议统一所有代理配置为同一个地址，并补充HTTPS_PROXY环境变量（cpanm访问MetaCPAN需要HTTPS代理）：

  export HTTP_PROXY=http://proxy-uat.mycompany.com:8080
  export HTTPS_PROXY=http://proxy-uat.mycompany.com:8080
  

• 手动指定CPAN镜像重试：
  cpanm默认依赖的cpanmetadb可能无法通过公司代理正常访问，尝试强制指定官方CPAN镜像执行安装：

  cpanm -v --mirror http://www.cpan.org App::cpanminus
  

• 直接安装已下载的包：
  既然已经成功下载了App-cpanminus-1.7047.tar.gz，可以跳过网络查找步骤，手动编译安装：

  tar zxf App-cpanminus-1.7047.tar.gz
  cd App-cpanminus-1.7047
  perl Makefile.PL
  make && make install
  

• 清理cpanm缓存：
  cpanm可能缓存了过期的CPAN索引，清理缓存后再重试安装：

  rm -rf ~/.cpanm
  

• 验证LWP的代理访问能力：
  cpanm依赖LWP库进行网络请求，测试LWP是否能正常访问cpanmetadb：

  perl -MLWP::Simple -e 'print get("https://cpanmetadb.plackperl.org/v1.0/package/App::cpanminus")'
  

  如果没有返回内容，说明LWP的代理配置存在问题，需要检查LWP相关的配置文件或环境变量。

内容的提问来源于stack exchange，提问作者XCodeHacker