Merge pull request #7 from aserto-dev/implement_graph

Add model graph

graph/graph.go

@@ -0,0 +1,102 @@
+package graph
+
+type Relations []string
+
+type Graph struct {
+	nodes     []string
+	adjMatrix [][]Relations
+}
+
+func NewGraph() *Graph {
+	return &Graph{
+		nodes:     make([]string, 0),
+		adjMatrix: make([][]Relations, 0),
+	}
+}
+
+func (g *Graph) AddNode(nodeName string) {
+	for _, vertexName := range g.nodes {
+		if nodeName == vertexName {
+			return
+		}
+	}
+	g.nodes = append(g.nodes, nodeName)
+	g.adjMatrix = append(g.adjMatrix, make([]Relations, 0))
+}
+
+func (g *Graph) AddEdge(source, dest, edgeName string) {
+	sourceIndex := g.findVertexIndexByName(source)
+	destIndex := g.findVertexIndexByName(dest)
+	if destIndex == -1 || sourceIndex == -1 {
+		return
+	}
+
+	if len(g.adjMatrix[sourceIndex]) == 0 {
+		g.adjMatrix[sourceIndex] = make([]Relations, len(g.nodes))
+	}
+
+	g.adjMatrix[sourceIndex][destIndex] = append(g.adjMatrix[sourceIndex][destIndex], edgeName)
+}
+
+func (g *Graph) dFS(source, dest int, visited []map[int]bool, traversal [][]string, index int) [][]string {
+	if len(traversal) < index+1 {
+		traversal = append(traversal, make([]string, 0))
+	}
+	traversal[index] = append(traversal[index], g.nodes[source])
+
+	if source == dest {
+		return traversal
+	} else {
+		for i := 0; i < len(g.nodes); i++ {
+			if len(g.adjMatrix[source]) > i && len(g.adjMatrix[source][i]) != 0 {
+				if len(visited[i]) == 0 {
+					visited[i] = make(map[int]bool, len(g.adjMatrix[source][i]))
+				}
+				for j := 0; j < len(g.adjMatrix[source][i]); j++ {
+					if visited[i][j] {
+						continue
+					}
+					visited[i][j] = true
+					if len(traversal) < index+1 {
+						traversal = append(traversal, make([]string, 0))
+					}
+					traversal[index] = append(traversal[index], g.adjMatrix[source][i][j])
+					traversal = g.dFS(i, dest, visited, traversal, index)
+					index++
+				}
+				visited[i] = make(map[int]bool, 0)
+			}
+		}
+	}
+
+	return traversal
+}
+
+func (g *Graph) FindPaths(startVertex, destVertx string) [][]string {
+	visited := make([]map[int]bool, len(g.nodes))
+	traversal := make([][]string, 0)
+	startIndex := g.findVertexIndexByName(startVertex)
+	destIndex := g.findVertexIndexByName(destVertx)
+	if startIndex == -1 || destIndex == -1 {
+		return traversal
+	}
+
+	traversal = g.dFS(startIndex, destIndex, visited, traversal, 0)
+	for i, paths := range traversal {
+		if paths[0] != startVertex {
+			traversal[i] = append([]string{startVertex}, paths...)
+		}
+
+	}
+
+	return traversal
+}
+
+func (g *Graph) findVertexIndexByName(name string) int {
+	for index, vertexName := range g.nodes {
+		if vertexName == name {
+			return index
+		}
+	}
+	return -1
+}

model/model.go

@@ -5,6 +5,8 @@ import (
 	"encoding/json"
 	"io"
 	"time"
+
+	"github.com/aserto-dev/azm/graph"
 )
 
 const ModelVersion int = 1
@@ -77,6 +79,26 @@ func New(r io.Reader) (*Model, error) {
 	return &m, nil
 }
 
+func (m *Model) GetGraph() *graph.Graph {
+	grph := graph.NewGraph()
+	for objectName := range m.Objects {
+		grph.AddNode(string(objectName))
+	}
+	for objectName, obj := range m.Objects {
+		for relName, rel := range obj.Relations {
+			for _, rl := range rel {
+				if string(rl.Direct) != "" {
+					grph.AddEdge(string(objectName), string(rl.Direct), string(relName))
+				} else if rl.Subject != nil {
+					grph.AddEdge(string(objectName), string(rl.Subject.Object), string(relName))
+				}
+			}
+		}
+	}
+
+	return grph
+}
+
 func (m *Model) Reader() (io.Reader, error) {
 	b := bytes.Buffer{}
 	enc := json.NewEncoder(&b)

model/model_test.go

@@ -226,3 +226,88 @@ func TestDiff(t *testing.T) {
 	stretch.Equal(t, len(diffM1WithM3.Removed.Relations), 1)
 	stretch.Equal(t, diffM1WithM3.Removed.Relations["document"], []model.RelationName{"parent_folder"})
 }
+
+func TestGraph(t *testing.T) {
+	m := model.Model{
+		Version: 1,
+		Objects: map[model.ObjectName]*model.Object{
+			model.ObjectName("user"): {
+				Relations: map[model.RelationName][]*model.Relation{
+					model.RelationName("rel_name"): {
+						&model.Relation{Direct: model.ObjectName("ext_obj")},
+					},
+				},
+			},
+			model.ObjectName("ext_obj"): {},
+			model.ObjectName("group"): {
+				Relations: map[model.RelationName][]*model.Relation{
+					model.RelationName("member"): {
+						&model.Relation{Direct: model.ObjectName("user")},
+						&model.Relation{Subject: &model.SubjectRelation{
+							Object:   model.ObjectName("group"),
+							Relation: model.RelationName("member"),
+						}},
+					},
+				},
+			},
+			model.ObjectName("folder"): {
+				Relations: map[model.RelationName][]*model.Relation{
+					model.RelationName("owner"): {
+						&model.Relation{Direct: model.ObjectName("user")},
+					},
+				},
+			},
+			model.ObjectName("document"): {
+				Relations: map[model.RelationName][]*model.Relation{
+					model.RelationName("parent_folder"): {
+						{Direct: model.ObjectName("folder")},
+					},
+					model.RelationName("writer"): {
+						{Direct: model.ObjectName("user")},
+					},
+					model.RelationName("reader"): {
+						{Direct: model.ObjectName("user")},
+						{Wildcard: model.ObjectName("user")},
+					},
+				},
+			},
+		},
+	}
+
+	docExtObjResults := [][]string{
+		{"document", "writer", "user", "rel_name", "ext_obj"},
+		{"document", "reader", "user", "rel_name", "ext_obj"},
+		{"document", "parent_folder", "folder", "owner", "user", "rel_name", "ext_obj"},
+	}
+
+	docUserResults := [][]string{
+		{"document", "writer", "user"},
+		{"document", "reader", "user"},
+		{"document", "parent_folder", "folder", "owner", "user"},
+	}
+
+	groupExtObjResults := [][]string{
+		{"group", "member", "group", "member", "user", "rel_name", "ext_obj"},
+		{"group", "member", "user", "rel_name", "ext_obj"},
+	}
+
+	graph := m.GetGraph()
+
+	search := graph.FindPaths("document", "ext_obj")
+	stretch.Equal(t, len(search), 3)
+	for _, expected := range docExtObjResults {
+		stretch.Contains(t, search, expected)
+	}
+
+	search = graph.FindPaths("document", "user")
+	stretch.Equal(t, len(search), 3)
+	for _, expected := range docUserResults {
+		stretch.Contains(t, search, expected)
+	}
+
+	search = graph.FindPaths("group", "ext_obj")
+	stretch.Equal(t, len(search), 2)
+	for _, expected := range groupExtObjResults {
+		stretch.Contains(t, search, expected)
+	}
+}