Merge pull request #4901 from chef/lcg/yum-readability

break yum classes out into files

1 files changed, 376 insertions, 0 deletions

diff --git a/lib/chef/provider/package/yum/yum_cache.rb b/lib/chef/provider/package/yum/yum_cache.rb
new file mode 100644
index 0000000000..fb25a91c8c
--- /dev/null
+++ b/lib/chef/provider/package/yum/yum_cache.rb
@@ -0,0 +1,376 @@
+
+# Author:: Adam Jacob (<adam@chef.io>)
+# Copyright:: Copyright 2008-2016, Chef Software, Inc.
+# License:: Apache License, Version 2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+require "chef/config"
+require "chef/provider/package"
+require "chef/mixin/which"
+require "chef/mixin/shell_out"
+require "singleton"
+require "chef/provider/package/yum/rpm_utils"
+
+class Chef
+  class Provider
+    class Package
+      class Yum < Chef::Provider::Package
+        # Cache for our installed and available packages, pulled in from yum-dump.py
+        class YumCache
+          include Chef::Mixin::Which
+          include Chef::Mixin::ShellOut
+          include Singleton
+
+          attr_accessor :yum_binary
+
+          def initialize
+            @rpmdb = RPMDb.new
+
+            # Next time @rpmdb is accessed:
+            #  :all       - Trigger a run of "yum-dump.py --options --installed-provides", updates
+            #               yum's cache and parses options from /etc/yum.conf. Pulls in Provides
+            #               dependency data for installed packages only - this data is slow to
+            #               gather.
+            #  :provides  - Same as :all but pulls in Provides data for available packages as well.
+            #               Used as a last resort when we can't find a Provides match.
+            #  :installed - Trigger a run of "yum-dump.py --installed", only reads the local rpm
+            #               db. Used between client runs for a quick refresh.
+            #  :none      - Do nothing, a call to one of the reload methods is required.
+            @next_refresh = :all
+
+            @allow_multi_install = []
+
+            @extra_repo_control = nil
+
+            # these are for subsequent runs if we are on an interval
+            Chef::Client.when_run_starts do
+              YumCache.instance.reload
+            end
+          end
+
+          attr_reader :extra_repo_control
+
+          # Cache management
+          #
+
+          def yum_dump_path
+            ::File.join(::File.dirname(__FILE__), "yum-dump.py")
+          end
+
+          def refresh
+            case @next_refresh
+            when :none
+              return nil
+            when :installed
+              reset_installed
+              # fast
+              opts = " --installed"
+            when :all
+              reset
+              # medium
+              opts = " --options --installed-provides"
+            when :provides
+              reset
+              # slow!
+              opts = " --options --all-provides"
+            else
+              raise ArgumentError, "Unexpected value in next_refresh: #{@next_refresh}"
+            end
+
+            if @extra_repo_control
+              opts << " #{@extra_repo_control}"
+            end
+
+            opts << " --yum-lock-timeout #{Chef::Config[:yum_lock_timeout]}"
+
+            one_line = false
+            error = nil
+
+            status = nil
+
+            begin
+              status = shell_out!("#{python_bin} #{yum_dump_path}#{opts}", :timeout => Chef::Config[:yum_timeout])
+              status.stdout.each_line do |line|
+                one_line = true
+
+                line.chomp!
+                if line =~ %r{\[option (.*)\] (.*)}
+                  if $1 == "installonlypkgs"
+                    @allow_multi_install = $2.split
+                  else
+                    raise Chef::Exceptions::Package, "Strange, unknown option line '#{line}' from yum-dump.py"
+                  end
+                  next
+                end
+
+                if line =~ %r{^(\S+) ([0-9]+) (\S+) (\S+) (\S+) \[(.*)\] ([i,a,r]) (\S+)$}
+                  name     = $1
+                  epoch    = $2
+                  version  = $3
+                  release  = $4
+                  arch     = $5
+                  provides = parse_provides($6)
+                  type     = $7
+                  repoid   = $8
+                else
+                  Chef::Log.warn("Problem parsing line '#{line}' from yum-dump.py! " +
+                                 "Please check your yum configuration.")
+                  next
+                end
+
+                case type
+                when "i"
+                  # if yum-dump was called with --installed this may not be true, but it's okay
+                  # since we don't touch the @available Set in reload_installed
+                  available = false
+                  installed = true
+                when "a"
+                  available = true
+                  installed = false
+                when "r"
+                  available = true
+                  installed = true
+                end
+
+                pkg = RPMDbPackage.new(name, epoch, version, release, arch, provides, installed, available, repoid)
+                @rpmdb << pkg
+              end
+
+              error = status.stderr
+            rescue Mixlib::ShellOut::CommandTimeout => e
+              Chef::Log.error("#{yum_dump_path} exceeded timeout #{Chef::Config[:yum_timeout]}")
+              raise(e)
+            end
+
+            if status.exitstatus != 0
+              raise Chef::Exceptions::Package, "Yum failed - #{status.inspect} - returns: #{error}"
+            else
+              unless one_line
+                Chef::Log.warn("Odd, no output from yum-dump.py. Please check " +
+                               "your yum configuration.")
+              end
+            end
+
+            # A reload method must be called before the cache is altered
+            @next_refresh = :none
+          end
+
+          def python_bin
+            yum_executable = which(yum_binary)
+            if yum_executable && shabang?(yum_executable)
+              shabang_or_fallback(extract_interpreter(yum_executable))
+            else
+              Chef::Log.warn("Yum executable not found or doesn't start with #!. Using default python.")
+              "/usr/bin/python"
+            end
+          rescue StandardError => e
+            Chef::Log.warn("An error occurred attempting to determine correct python executable. Using default.")
+            Chef::Log.debug(e)
+            "/usr/bin/python"
+          end
+
+          def extract_interpreter(file)
+            ::File.open(file, "r", &:readline)[2..-1].strip
+          end
+
+          # dnf based systems have a yum shim that has /bin/bash as the interpreter. Don't use this.
+          def shabang_or_fallback(interpreter)
+            if interpreter == "/bin/bash"
+              Chef::Log.warn("Yum executable interpreter is /bin/bash. Falling back to default python.")
+              "/usr/bin/python"
+            else
+              interpreter
+            end
+          end
+
+          def shabang?(file)
+            ::File.open(file, "r") do |f|
+              f.read(2) == '#!'
+            end
+          rescue Errno::ENOENT
+            false
+          end
+
+          def reload
+            @next_refresh = :all
+          end
+
+          def reload_installed
+            @next_refresh = :installed
+          end
+
+          def reload_provides
+            @next_refresh = :provides
+          end
+
+          def reset
+            @rpmdb.clear
+          end
+
+          def reset_installed
+            @rpmdb.clear_installed
+          end
+
+          # Querying the cache
+          #
+
+          # Check for package by name or name+arch
+          def package_available?(package_name)
+            refresh
+
+            if @rpmdb.lookup(package_name)
+              return true
+            else
+              if package_name =~ %r{^(.*)\.(.*)$}
+                pkg_name = $1
+                pkg_arch = $2
+
+                if matches = @rpmdb.lookup(pkg_name)
+                  matches.each do |m|
+                    return true if m.arch == pkg_arch
+                  end
+                end
+              end
+            end
+
+            return false
+          end
+
+          # Returns a array of packages satisfying an RPMDependency
+          def packages_from_require(rpmdep)
+            refresh
+            @rpmdb.whatprovides(rpmdep)
+          end
+
+          # Check if a package-version.arch is available to install
+          def version_available?(package_name, desired_version, arch = nil)
+            version(package_name, arch, true, false) do |v|
+              return true if desired_version == v
+            end
+
+            return false
+          end
+
+          # Return the source repository for a package-version.arch
+          def package_repository(package_name, desired_version, arch = nil)
+            package(package_name, arch, true, false) do |pkg|
+              return pkg.repoid if desired_version == pkg.version.to_s
+            end
+
+            return nil
+          end
+
+          # Return the latest available version for a package.arch
+          def available_version(package_name, arch = nil)
+            version(package_name, arch, true, false)
+          end
+          alias :candidate_version :available_version
+
+          # Return the currently installed version for a package.arch
+          def installed_version(package_name, arch = nil)
+            version(package_name, arch, false, true)
+          end
+
+          # Return an array of packages allowed to be installed multiple times, such as the kernel
+          def allow_multi_install
+            refresh
+            @allow_multi_install
+          end
+
+          def enable_extra_repo_control(arg)
+            # Don't touch cache if it's the same repos as the last load
+            unless @extra_repo_control == arg
+              @extra_repo_control = arg
+              reload
+            end
+          end
+
+          def disable_extra_repo_control
+            # Only force reload when set
+            if @extra_repo_control
+              @extra_repo_control = nil
+              reload
+            end
+          end
+
+          private
+
+          def version(package_name, arch = nil, is_available = false, is_installed = false)
+            package(package_name, arch, is_available, is_installed) do |pkg|
+              if block_given?
+                yield pkg.version.to_s
+              else
+                # first match is latest version
+                return pkg.version.to_s
+              end
+            end
+
+            if block_given?
+              return self
+            else
+              return nil
+            end
+          end
+
+          def package(package_name, arch = nil, is_available = false, is_installed = false)
+            refresh
+            packages = @rpmdb[package_name]
+            if packages
+              packages.each do |pkg|
+                if is_available
+                  next unless @rpmdb.available?(pkg)
+                end
+                if is_installed
+                  next unless @rpmdb.installed?(pkg)
+                end
+                if arch
+                  next unless pkg.arch == arch
+                end
+
+                if block_given?
+                  yield pkg
+                else
+                  # first match is latest version
+                  return pkg
+                end
+              end
+            end
+
+            if block_given?
+              return self
+            else
+              return nil
+            end
+          end
+
+          # Parse provides from yum-dump.py output
+          def parse_provides(string)
+            ret = []
+            # ['atk = 1.12.2-1.fc6', 'libatk-1.0.so.0']
+            string.split(", ").each do |seg|
+              # 'atk = 1.12.2-1.fc6'
+              if seg =~ %r{^'(.*)'$}
+                ret << RPMProvide.parse($1)
+              end
+            end
+
+            return ret
+          end
+
+        end # YumCache
+      end
+    end
+  end
+end