这些是我的软件版本：
这是我的Capfile：
require "capistrano/setup"
require "capistrano/deploy"
require "capistrano/scm/git"
install_plugin Capistrano::SCM::Git
require "capistrano/rvm"
require "capistrano/bundler"
require "capistrano/rails/assets"
require "capistrano/rails/migrations"
require "capistrano/puma"
install_plugin Capistrano::Puma
配置/ deploy.rb：
server '192.168.0.1', port: 22, roles: [:web, :app, :db], primary: true
set :application, "testapp"
set :repo_url, "git@github.com:username/testapp.git"
set :user, 'deploy'
set :puma_threads, [4, 16]
set :puma_workers, 0
set :pty, true
set :use_sudo, false
set :stage, :production
set :deploy_via, :remote_cache
set :deploy_to, "/home/#{fetch(:user)}/apps/#{fetch(:application)}"
set :puma_bind, "unix://#{shared_path}/tmp/sockets/#{fetch(:application)}-puma.sock"
set :puma_state, "#{shared_path}/tmp/pids/puma.state"
set :puma_pid, "#{shared_path}/tmp/pids/puma.pid"
set :puma_access_log, "#{release_path}/log/puma.error.log"
set :puma_error_log, "#{release_path}/log/puma.access.log"
set :ssh_options, { forward_agent: true, user: fetch(:user), keys: %w(~/.ssh/id_rsa.pub) }
set :puma_preload_app, true
set :puma_worker_timeout, nil
set :puma_init_active_record, true # Change to false when not using ActiveRecord
namespace :puma do
desc 'Create Directories for Puma Pids and Socket'
task :make_dirs do
on roles(:app) do
execute "mkdir #{shared_path}/tmp/sockets -p"
execute "mkdir #{shared_path}/tmp/pids -p"
end
end
before :start, :make_dirs
end
namespace :deploy do
desc "Make sure local git is in sync with remote."
task :check_revision do
on roles(:app) do
unless `git rev-parse HEAD` == `git rev-parse origin/master`
puts "WARNING: HEAD is not the same as origin/master"
puts "Run `git push` to sync changes."
exit
end
end
end
desc 'Initial Deploy'
task :initial do
on roles(:app) do
before 'deploy:restart', 'puma:start'
invoke 'deploy'
end
end
desc 'Restart application'
task :restart do
on roles(:app), in: :sequence, wait: 5 do
invoke 'puma:restart'
end
end
当我跑cap production deploy:initial时，我遇到了这些错误：
Results logged to
/home/deploy/apps/testapp/shared/bundle/ruby/2.2.0/extensions/x86_64-linux/2.2.0/nokogiri-1.8.0/gem_make.out
An error occurred while installing nokogiri (1.8.0), and Bundler cannot
continue.
Make sure that `gem install nokogiri -v '1.8.0'` succeeds before bundling.
In Gemfile:
rails was resolved to 4.2.0, which depends on
actionmailer was resolved to 4.2.0, which depends on
actionpack was resolved to 4.2.0, which depends on
actionview was resolved to 4.2.0, which depends on
rails-dom-testing was resolved to 1.0.8, which depends on
nokogiri
bundle stderr: Nothing written
** DEPLOY FAILED
** Refer to log/capistrano.log for details. Here are the last 20 lines:
extconf failed, exit code 1
Gem files will remain installed in
/home/deploy/apps/testapp/shared/bundle/ruby/2.2.0/gems/nokogiri-1.8.0 for
inspection.
Results logged to
/home/deploy/apps/testapp/shared/bundle/ruby/2.2.0/extensions/x86_64-linux/2.2.0/nokogiri-1.8.0/gem_make.out
An error occurred while installing nokogiri (1.8.0), and Bundler cannot
continue.
Make sure that `gem install nokogiri -v '1.8.0'` succeeds before bundling.
In Gemfile:
rails was resolved to 4.2.0, which depends on
actionmailer was resolved to 4.2.0, which depends on
DEBUG [419bf769] actionpack was resolved to 4.2.0, which depends on
actionview was resolved to 4.2.0, which depends on
rails-dom-testing was resolved to 1.0.8, which depends on
nokogiri
我在远程服务器上安装了ruby 2.2.1。为什么在这里使用2.2.0？
我还删除了Gemfile.lock文件并再次运行bundle。该文件类似于：
...
loofah (2.0.3)
nokogiri (>= 1.5.9)
mail (2.6.6)
mime-types (>= 1.16, < 4)
mime-types (3.1)
mime-types-data (~> 3.2015)
mime-types-data (3.2016.0521)
mini_portile2 (2.2.0)
minitest (5.10.2)
multi_json (1.12.1)
net-scp (1.2.1)
net-ssh (>= 2.6.5)
net-ssh (4.1.0)
nokogiri (1.8.0)
mini_portile2 (~> 2.2.0)
puma (3.9.1)
rack (1.6.8)
rack-test (0.6.3)
rack (>= 1.0)
rails (4.2.0)
actionmailer (= 4.2.0)
actionpack (= 4.2.0)
actionview (= 4.2.0)
activejob (= 4.2.0)
activemodel (= 4.2.0)
activerecord (= 4.2.0)
activesupport (= 4.2.0)
bundler (>= 1.3.0, < 2.0)
railties (= 4.2.0)
sprockets-rails
rails-deprecated_sanitizer (1.0.3)
activesupport (>= 4.2.0.alpha)
rails-dom-testing (1.0.8)
activesupport (>= 4.2.0.beta, < 5.0)
nokogiri (~> 1.6)
rails-deprecated_sanitizer (>= 1.0.1)
...
PLATFORMS
ruby
DEPENDENCIES
byebug
capistrano
capistrano-bundler
capistrano-rails
capistrano-rvm
capistrano3-puma
coffee-rails (~> 4.1.0)
jbuilder (~> 2.0)
jquery-rails
puma
rails (= 4.2.0)
sass-rails (~> 5.0)
sdoc (~> 0.4.0)
spring
sqlite3
turbolinks
uglifier (>= 1.3.0)
web-console (~> 2.0)
答案 0 :(得分：1)
有时一次又一次地尝试，我终于找到了原因。
这只是为什么无法安装nokogiri。
在目标服务器上，应首先安装这些必需的软件包：
sudo apt-get install zlib1g-dev libssl-dev libreadline-dev libyaml-dev libxml2-dev libxslt-dev
nokogiri gem取决于这些库：libxml2-dev，libxslt-dev（可能）。