Output cluster attributes in CSV

lib/mosaik/graph/graph.rb

@@ -165,6 +165,7 @@ def to_csv
         # Set of visited edges (to avoid duplicates in undirected graphs)
         visited = Set.new
 
+        # rubocop:disable Metrics/BlockLength
         CSV.generate do |csv|
           # VERTICES
           # Collect all vertex attributes
@@ -208,19 +209,29 @@ def to_csv
 
           next unless clusters.any?
 
+          # CLUSTERS
           # Separator
           csv << ["--"]
 
+          # VERTICES
+          # Collect all vertex attributes
+          attributes = clusters
+            .values
+            .flat_map(&:attributes)
+            .flat_map(&:keys)
+            .uniq
+
           # Header
-          csv << ["vertex", "cluster"]
+          csv << ["vertex", "cluster", *attributes]
 
           # Add clusters using a cluster mapping
           clusters.each do |cluster_id, cluster|
             cluster.vertices.each do |vertex|
-              csv << [vertex.id, cluster_id]
+              csv << [vertex.id, cluster_id, *attributes.map { |attr| cluster.attributes[attr] }]
             end
           end
         end
+        # rubocop:enable Metrics/BlockLength
       end
 
       sig { returns(String) }
@@ -255,10 +266,10 @@ def self.from_csv(csv, directed: true)
 
         # Add clusters from the cluster mapping
         CSV.new(clusters, headers: true, header_converters: :symbol, converters: :numeric).each do |row|
-          row => { vertex:, cluster: }
+          row => { vertex:, cluster:, **attributes }
 
           graph
-            .find_or_add_cluster(cluster)
+            .find_or_add_cluster(cluster, attributes.symbolize_keys)
             .add_vertex(graph.find_or_add_vertex(vertex))
         end
 

spec/mosaik/graph/graph_spec.rb

@@ -478,11 +478,11 @@
         graph.add_edge("vertex1", "vertex2")
         graph.add_edge("vertex2", "vertex3", method: "method", weight: 1.0)
 
-        c1 = graph.add_cluster("cluster1")
+        c1 = graph.add_cluster("cluster1", type: "database")
         c1.add_vertex(v1)
         c1.add_vertex(v2)
 
-        c2 = graph.add_cluster("cluster2")
+        c2 = graph.add_cluster("cluster2", type: "microservice")
         c2.add_vertex(v3)
 
         graph.add_cluster("cluster3")
@@ -497,10 +497,10 @@
           vertex1,vertex2,,
           vertex2,vertex3,method,1.0
           --
-          vertex,cluster
-          vertex1,cluster1
-          vertex2,cluster1
-          vertex3,cluster2
+          vertex,cluster,type
+          vertex1,cluster1,database
+          vertex2,cluster1,database
+          vertex3,cluster2,microservice
         CSV
       end
     end
@@ -582,10 +582,10 @@
           vertex1,vertex2,,
           vertex2,vertex3,method,1.0
           --
-          vertex,cluster
-          vertex1,cluster1
-          vertex2,cluster1
-          vertex3,cluster2
+          vertex,cluster,type
+          vertex1,cluster1,database
+          vertex2,cluster1,database
+          vertex3,cluster2,microservice
         CSV
 
         graph = described_class.from_csv(csv, directed: true)
@@ -605,7 +605,10 @@
 
         expect(graph.clusters.keys).to eq ["cluster1", "cluster2"]
         expect(graph.find_cluster("cluster1").vertices.map(&:id)).to eq ["vertex1", "vertex2"]
+        expect(graph.find_cluster("cluster1").attributes).to eq type: "database"
+
         expect(graph.find_cluster("cluster2").vertices.map(&:id)).to eq ["vertex3"]
+        expect(graph.find_cluster("cluster2").attributes).to eq type: "microservice"
       end
     end
   end