lib/mixlib/install/backend/base.rb in mixlib-install-1.0.10 vs lib/mixlib/install/backend/base.rb in mixlib-install-1.0.11

@@ -24,16 +24,89 @@
 
         def initialize(options)
           @options = options
         end
 
+        #
+        # Returns the list of artifacts from the configured backend based on the
+        # configured product_name, product_version and channel.
+        #
+        # @abstract Subclasses should define this method.
+        #
+        # @return Array<ArtifactInfo>
+        #   List of ArtifactInfo objects for the available artifacts.
+        def available_artifacts
+          raise "Must implement available_artifacts method that returns Array<ArtifactInfo>"
+        end
+
+        #
+        # See #filter_artifacts
         def info
-          raise "Must implement info method that returns ArtifactInfo or Array<ArtifactInfo>"
+          filter_artifacts(available_artifacts)
         end
 
-        def endpoint
-          raise "Must implement endpoint method that returns endpoint String"
+        #
+        # Returns true if platform filters are available, false otherwise.
+        #
+        # Note that we assume #set_platform_info method is used on the Options
+        # class to set the platform options.
+        #
+        # @return TrueClass, FalseClass
+        def platform_filters_available?
+          !options.platform.nil?
         end
+
+        #
+        # Filters and returns the available artifacts based on the configured
+        # platform filtering options.
+        #
+        # @return ArtifactInfo, Array<ArtifactInfo>, []
+        #   If the result is a single artifact, this returns ArtifactInfo.
+        #   If the result is a list of artifacts, this returns Array<ArtifactInfo>.
+        #   If no suitable artifact is found, this returns [].
+        def filter_artifacts(artifacts)
+          return artifacts unless platform_filters_available?
+
+          # First filter the artifacts based on the platform and architecture
+          artifacts.select! do |a|
+            a.platform == options.platform && a.architecture == options.architecture
+          end
+
+          # Now we are going to filter based on platform_version.
+          # We will return the artifact with an exact match if available.
+          # Otherwise we will search for a compatible artifact and return it
+          # if the compat options is set.
+          closest_compatible_artifact = nil
+
+          artifacts.each do |a|
+            return a if a.platform_version == options.platform_version
+
+            # We skip the artifacts produced for windows since their platform
+            # version is always set to 2008r2 which breaks our `to_f` comparison.
+            next if a.platform == "windows"
+
+            # Calculate the closest compatible version.
+            # For an artifact to be compatible it needs to be smaller than the
+            # platform_version specified in options.
+            # To find the closest compatible one we keep a max of the compatible
+            # artifacts.
+            if closest_compatible_artifact.nil? ||
+                (a.platform_version.to_f > closest_compatible_artifact.platform_version.to_f &&
+                  a.platform_version.to_f < options.platform_version.to_f )
+              closest_compatible_artifact = a
+            end
+          end
+
+          # If the compat flag is set and if we have found a compatible artifact
+          # we are going to use it.
+          if options.platform_version_compatibility_mode && closest_compatible_artifact
+            return closest_compatible_artifact
+          end
+
+           # Otherwise, we return an empty array indicating we do not have any matching artifacts
+          return []
+        end
+
       end
     end
   end
 end