我可以找到使用gem list安装的宝石，但它没有告诉我宝石的安装位置。
我怎样才能找到宝石的位置，如何在安装宝石之前知道它？
答案 0 :(得分：313)
使用gem environment了解您的宝石环境：
RubyGems Environment:
- RUBYGEMS VERSION: 2.1.5
- RUBY VERSION: 2.0.0 (2013-06-27 patchlevel 247) [x86_64-darwin12.4.0]
- INSTALLATION DIRECTORY: /Users/ttm/.rbenv/versions/2.0.0-p247/lib/ruby/gems/2.0.0
- RUBY EXECUTABLE: /Users/ttm/.rbenv/versions/2.0.0-p247/bin/ruby
- EXECUTABLE DIRECTORY: /Users/ttm/.rbenv/versions/2.0.0-p247/bin
- SPEC CACHE DIRECTORY: /Users/ttm/.gem/specs
- RUBYGEMS PLATFORMS:
- ruby
- x86_64-darwin-12
- GEM PATHS:
- /Users/ttm/.rbenv/versions/2.0.0-p247/lib/ruby/gems/2.0.0
- /Users/ttm/.gem/ruby/2.0.0
- GEM CONFIGURATION:
- :update_sources => true
- :verbose => true
- :backtrace => false
- :bulk_threshold => 1000
- REMOTE SOURCES:
- https://rubygems.org/
- SHELL PATH:
- /Users/ttm/.rbenv/versions/2.0.0-p247/bin
- /Users/ttm/.rbenv/libexec
- /Users/ttm/.rbenv/plugins/ruby-build/bin
- /Users/ttm/perl5/perlbrew/bin
- /Users/ttm/perl5/perlbrew/perls/perl-5.18.1/bin
- /Users/ttm/.pyenv/shims
- /Users/ttm/.pyenv/bin
- /Users/ttm/.rbenv/shims
- /Users/ttm/.rbenv/bin
- /Users/ttm/bin
- /usr/local/mysql-5.6.12-osx10.7-x86_64/bin
- /Users/ttm/libsmi/bin
- /usr/local/bin
- /usr/bin
- /bin
- /usr/sbin
- /sbin
- /usr/local/bin
请注意以下两个部分：
INSTALLATION DIRECTORY GEM PATHS 答案 1 :(得分：121)
我发现使用以下命令获取库文件的位置很有用：
gem which *gemname*
答案 2 :(得分：63)
安装宝石之后，如果你想知道特定宝石的位置。尝试输入：
gem list
您将能够看到已安装的宝石列表。现在使用bundle show并命名您想知道其路径的gem，如下所示：
bundle show <gemName>
答案 3 :(得分：46)
要完成其他答案，gem-path gem可以找到特定gem的安装路径。
安装：
gem install gem-path
用法：
gem path rails
=> /home/cbliard/.rvm/gems/ruby-2.1.5/gems/rails-4.0.13
gem path rails '< 4'
=> /home/cbliard/.rvm/gems/ruby-2.1.5/gems/rails-3.2.21
这非常方便，因为您可以使用它来grep或编辑文件：
grep -R 'Internal server error' "$(gem path thin)"
subl "$(gem path thin)"
答案 4 :(得分：27)
您可以通过运行gem help commands然后选择正确的命令从命令提示符进行检查：
kirti@kirti-Aspire-5733Z:~$ gem help commands
GEM commands are:
build Build a gem from a gemspec
cert Manage RubyGems certificates and signing settings
check Check a gem repository for added or missing files
cleanup Clean up old versions of installed gems in the local
repository
contents Display the contents of the installed gems
dependency Show the dependencies of an installed gem
environment Display information about the RubyGems environment
fetch Download a gem and place it in the current directory
generate_index Generates the index files for a gem server directory
help Provide help on the 'gem' command
install Install a gem into the local repository
list Display gems whose name starts with STRING
lock Generate a lockdown list of gems
mirror Mirror all gem files (requires rubygems-mirror)
outdated Display all gems that need updates
owner Manage gem owners on RubyGems.org.
pristine Restores installed gems to pristine condition from
files located in the gem cache
push Push a gem up to RubyGems.org
query Query gem information in local or remote repositories
rdoc Generates RDoc for pre-installed gems
regenerate_binstubs Re run generation of executable wrappers for gems.
search Display all gems whose name contains STRING
server Documentation and gem repository HTTP server
sources Manage the sources and cache file RubyGems uses to
search for gems
specification Display gem specification (in yaml)
stale List gems along with access times
uninstall Uninstall gems from the local repository
unpack Unpack an installed gem to the current directory
update Update installed gems to the latest version
which Find the location of a library file you can require
yank Remove a specific gem version release from
RubyGems.org
For help on a particular command, use 'gem help COMMAND'.
Commands may be abbreviated, so long as they are unambiguous.
e.g. 'gem i rake' is short for 'gem install rake'.
kirti@kirti-Aspire-5733Z:~$
现在从上面我可以看到命令environment很有帮助。所以我会这样做：
kirti@kirti-Aspire-5733Z:~$ gem help environment
Usage: gem environment [arg] [options]
Common Options:
-h, --help Get help on this command
-V, --[no-]verbose Set the verbose level of output
-q, --quiet Silence commands
--config-file FILE Use this config file instead of default
--backtrace Show stack backtrace on errors
--debug Turn on Ruby debugging
Arguments:
packageversion display the package version
gemdir display the path where gems are installed
gempath display path used to search for gems
version display the gem format version
remotesources display the remote gem servers
platform display the supported gem platforms
<omitted> display everything
Summary:
Display information about the RubyGems environment
Description:
The RubyGems environment can be controlled through command line arguments,
gemrc files, environment variables and built-in defaults.
Command line argument defaults and some RubyGems defaults can be set in a
~/.gemrc file for individual users and a /etc/gemrc for all users. These
files are YAML files with the following YAML keys:
:sources: A YAML array of remote gem repositories to install gems from
:verbose: Verbosity of the gem command. false, true, and :really are the
levels
:update_sources: Enable/disable automatic updating of repository metadata
:backtrace: Print backtrace when RubyGems encounters an error
:gempath: The paths in which to look for gems
:disable_default_gem_server: Force specification of gem server host on
push
<gem_command>: A string containing arguments for the specified gem command
Example:
:verbose: false
install: --no-wrappers
update: --no-wrappers
:disable_default_gem_server: true
RubyGems' default local repository can be overridden with the GEM_PATH and
GEM_HOME environment variables. GEM_HOME sets the default repository to
install into. GEM_PATH allows multiple local repositories to be searched for
gems.
If you are behind a proxy server, RubyGems uses the HTTP_PROXY,
HTTP_PROXY_USER and HTTP_PROXY_PASS environment variables to discover the
proxy server.
If you would like to push gems to a private gem server the RUBYGEMS_HOST
environment variable can be set to the URI for that server.
If you are packaging RubyGems all of RubyGems' defaults are in
lib/rubygems/defaults.rb. You may override these in
lib/rubygems/defaults/operating_system.rb
kirti@kirti-Aspire-5733Z:~$
最后为了告诉你你的要求，我会这样做：
kirti@kirti-Aspire-5733Z:~$ gem environment gemdir
/home/kirti/.rvm/gems/ruby-2.0.0-p0
kirti@kirti-Aspire-5733Z:~$ gem environment gempath
/home/kirti/.rvm/gems/ruby-2.0.0-p0:/home/kirti/.rvm/gems/ruby-2.0.0-p0@global
kirti@kirti-Aspire-5733Z:~$
答案 5 :(得分：12)
gem env就像gem environment一样。保存一些打字。
# gem env
RubyGems Environment:
- RUBYGEMS VERSION: 2.0.14
- RUBY VERSION: 2.0.0 (2014-02-24 patchlevel 451) [i686-linux]
- INSTALLATION DIRECTORY: /usr/local/lib/ruby/gems/2.0.0
- RUBY EXECUTABLE: /usr/local/bin/ruby
- EXECUTABLE DIRECTORY: /usr/local/bin
- RUBYGEMS PLATFORMS:
- ruby
- x86-linux
- GEM PATHS:
- /usr/local/lib/ruby/gems/2.0.0
- /root/.gem/ruby/2.0.0
- GEM CONFIGURATION:
- :update_sources => true
- :verbose => true
- :backtrace => false
- :bulk_threshold => 1000
- REMOTE SOURCES:
- https://rubygems.org/
答案 6 :(得分：6)
您可以欺骗gem open显示宝石路径：
VISUAL=echo gem open gem-name
示例：
VISUAL=echo gem open rails
=> /usr/local/opt/asdf/installs/ruby/2.4.3/lib/ruby/gems/2.4.0/gems/rails-5.1.4
答案 7 :(得分：1)
如果您使用的是rvm工具，则可以运行以下命令以打印gem路径：
rvm gemdir
OR
echo $GEM_HOME
答案 8 :(得分：1)
这有效，并为您提供了每个gem的安装路径。尝试进行多阶段docker构建时，此超级有用。您可以在捆绑后安装的特定目录中复制。
bash-4.4# gem list -d
输出：：
aasm (5.0.6)
Authors: Thorsten Boettger, Anil Maurya
Homepage: https://github.com/aasm/aasm
License: MIT
Installed at: /usr/local/bundle
State machine mixin for Ruby objects
答案 9 :(得分：0)
gem env列出了可以安装宝石 的位置，但是可以在10个或更多位置。如果您想知道特定的宝石安装在哪里，可以执行：
gem list -d <gemname>
示例输出：
tilt (2.0.9)
Author: Ryan Tomayko
Homepage: http://github.com/rtomayko/tilt/
License: MIT
Installed at: /opt/rubies/ruby-2.5.3/lib/ruby/gems/2.5.0
Generic interface to multiple Ruby template engines