Add a new API to manage products and packages

* The implementation is not finished.
* libzypp is the only implemented backend.

library/packages/src/lib/y2packager/backend.rb

@@ -0,0 +1,48 @@
+# Copyright (c) [2021] SUSE LLC
+#
+# All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of version 2 of the GNU General Public License as published
+# by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, contact SUSE LLC.
+#
+# To contact SUSE LLC about this file by physical or electronic mail, you may
+# find current contact information at www.suse.com.
+
+module Y2Packager
+  # Implements support for a software management system
+  #
+  # To implement support for an additional backend, just inherit from this class
+  # and implement the corresponding methods (e.g., #probe, #repositories, #search, etc.).
+  class Backend
+    # Initializes the backend
+    def probe; end
+
+    # Returns the list of repositories
+    #
+    # @return [Array<Repository>]
+    def repositories
+      []
+    end
+
+    # Returns the resolvables according to the given conditions and properties
+    #
+    # @todo Return a ResolvablesCollection instance.
+    #
+    # @param conditions [Hash<Symbol,String>] Search conditions (e.g., { name: "SLES" }
+    # @param properties [Array<Symbol>] List of properties to include in the result.
+    #   The default list is defined by each backend.
+    # @return [Array<Resolvable>]
+    def search(*)
+      []
+    end
+  end
+end

library/packages/src/lib/y2packager/libzypp_backend.rb

@@ -0,0 +1,84 @@
+# Copyright (c) [2021] SUSE LLC
+#
+# All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of version 2 of the GNU General Public License as published
+# by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, contact SUSE LLC.
+#
+# To contact SUSE LLC about this file by physical or electronic mail, you may
+# find current contact information at www.suse.com.
+
+require "yast"
+require "y2packager/backend"
+require "y2packager/rpm_repo"
+require "y2packager/package"
+require "y2packager/product"
+
+module Y2Packager
+  # Backend implementation for libzypp
+  class LibzyppBackend < Backend
+    # Initialize the libzypp subsystem using the pkg-bindings
+    def probe
+      Yast.import "Pkg"
+      Yast.import "PackageLock"
+      Yast::Pkg.TargetInitialize("/")
+      Yast::Pkg.TargetLoad
+      Yast::Pkg.SourceRestore
+      Yast::Pkg.SourceLoad
+    end
+
+    # Reads the repositories from the system
+    #
+    # @return [Array<RpmRepo>]
+    def repositories
+      Yast::Pkg.SourceGetCurrent(false).map do |repo_id|
+        repo = Yast::Pkg.SourceGeneralData(repo_id)
+        raise NotFound if repo.nil?
+
+        RpmRepo.new(repo_id: repo_id, repo_alias: repo["alias"],
+          enabled: repo["enabled"], name: repo["name"],
+          autorefresh: repo["autorefresh"], url: repo["raw_url"],
+          product_dir: repo["product_dir"])
+      end
+    end
+
+    # @todo Allow passing multiple statuses
+    # @todo Use a set of default properties so you do not need to explictly pass them
+    def search(conditions:, properties:)
+      resolvables = Yast::Pkg.Resolvables(
+        conditions,
+        (properties + [:kind]).uniq
+      )
+
+      resolvables.map do |res|
+        meth = "hash_to_#{res["kind"]}"
+        next res unless respond_to?(meth, true)
+
+        send(meth, res)
+      end
+    end
+
+  private
+
+    def hash_to_product(hsh)
+      Y2Packager::Product.new(
+        name: hsh["name"], arch: hsh["arch"], version: hsh["version"]
+      )
+    end
+
+    def hash_to_package(hsh)
+      Y2Packager::Package.new(
+        hsh["name"], hsh["source"], hsh["version"]
+      )
+    end
+  end
+end

library/packages/src/lib/y2packager/rpm_repo.rb

@@ -0,0 +1,29 @@
+# Copyright (c) [2021] SUSE LLC
+#
+# All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of version 2 of the GNU General Public License as published
+# by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, contact SUSE LLC.
+#
+# To contact SUSE LLC about this file by physical or electronic mail, you may
+# find current contact information at www.suse.com.
+
+require "y2packager/repository"
+
+module Y2Packager
+  # Represents an RPM packages repository
+  #
+  # @todo Move here the RPM specific logic from the Repository class
+  #   and rename Repository to Origin.
+  class RpmRepo < Repository
+  end
+end

library/packages/src/lib/y2packager/software_manager.rb

@@ -0,0 +1,91 @@
+# Copyright (c) [2021] SUSE LLC
+#
+# All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of version 2 of the GNU General Public License as published
+# by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, contact SUSE LLC.
+#
+# To contact SUSE LLC about this file by physical or electronic mail, you may
+# find current contact information at www.suse.com.
+
+require "y2packager/repository"
+require "y2packager/libzypp_backend"
+require "y2packager/software_search"
+
+module Y2Packager
+  # This class represents the software management subsystem
+  #
+  # It allows managing software repositories, installing/removing software, and so on.
+  #
+  # @example Initialize the software management subsystem
+  #   software = SoftwareManagement.new(LibzyppBackend.new)
+  #   software.probe
+  #
+  # @example Convenience method to initialize the software manager
+  #   SoftwareManager.probe
+  #   SoftwareManager.current #=> #<Y2Packager::SoftwareManager...>
+  #
+  class SoftwareManager
+    # @return [Array<Backend>] List of known backends
+    attr_reader :backends
+
+    class << self
+      # Returns a SoftwareManager instance and keeps the reference for the future
+      #
+      # @note At this time, it always initializes the system using the LibzyppBackend.
+      # @return [SoftwareManagement] A SoftwareManagement instance for the current system
+      def current
+        @current ||= new([LibzyppBackend.new])
+      end
+
+      def reset
+        @current = nil
+      end
+    end
+
+    # @param backends [Array<Backend>] List of backends to use
+    def initialize(backends)
+      @backends = backends
+    end
+
+    # Initialize the software subsystem
+    def probe
+      backends.each(&:probe)
+    end
+
+    # Commits the changes defined in the software proposal
+    #
+    # @param [SoftwareProposal]
+    def commit(_proposal)
+      # ask the backends to install the given packages/apps
+      raise NotImplementedError
+    end
+
+    # List of repositories from all the backends
+    #
+    # @return [Array<Repository>] Defined repositories from all backends
+    def repositories
+      backends.each_with_object([]) do |backend, all|
+        all.concat(backend.repositories)
+      end
+    end
+
+    # Returns a search object which includes all backends
+    #
+    # @todo Allow disabling any backend.
+    #
+    # @return [SoftwareSearch]
+    def search
+      SoftwareSearch.new(*backends)
+    end
+  end
+end

library/packages/src/lib/y2packager/software_search.rb

@@ -0,0 +1,88 @@
+# Copyright (c) [2021] SUSE LLC
+#
+# All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of version 2 of the GNU General Public License as published
+# by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, contact SUSE LLC.
+#
+# To contact SUSE LLC about this file by physical or electronic mail, you may
+# find current contact information at www.suse.com.
+
+module Y2Packager
+  # Query the software manager for resolvables (packages, products, applications,
+  # and so on).
+  #
+  # Should we have two different classes? One for the conditions/properties
+  # and the other one that represents the query itself. See Backend#search for
+  # an explanation.
+  #
+  # The SoftwareSearch contains additional information, like the list of backends.
+  #
+  # @example Search by name
+  #   query = SoftwareSearch.new(backend)
+  #
+  class SoftwareSearch
+    include Enumerable
+
+    # @return [Array<Backend>] Limit the search to these backends
+    attr_reader :backends
+
+    # @return [Array<Symbol>] Properties to include
+    attr_reader :properties
+
+    # @return [Hash<Symbol,String>] A hash describing the conditions (e.g., {
+    #   name: "yast2" })
+    attr_reader :conditions
+
+    # attributes required for identifying a resolvable
+    BASE_ATTRIBUTES = [:kind, :name, :version, :arch, :source].freeze
+
+    def initialize(*backends)
+      @backends = backends # limit the query to these backends
+      @properties = BASE_ATTRIBUTES.dup
+      @conditions = {}
+    end
+
+    def named(name)
+      with(name: name)
+      self
+    end
+
+    def including(*names)
+      @properties.concat(names)
+      self
+    end
+
+    def excluding(*names)
+      names.each { |a| @properties.delete(a) }
+      self
+    end
+
+    def with(conds = {})
+      @conditions.merge!(conds)
+      self
+    end
+
+    # @todo Rely on a ResolvablesCollection instead
+    def each(&block)
+      resolvables.each(&block)
+    end
+
+  private
+
+    def resolvables
+      backends.each_with_object([]) do |backend, all|
+        all.concat(backend.search(conditions: conditions, properties: properties))
+      end
+    end
+  end
+end