Added support for configurable levels of circular reference checking #113 #130

Signed-off-by: quobix <dave@quobix.com>

index/circular_reference_result.go

@@ -8,6 +8,8 @@ type CircularReferenceResult struct {
 	Start               *Reference
 	LoopIndex           int
 	LoopPoint           *Reference
+	IsArrayResult       bool   // if this result comes from an array loop.
+	PolymorphicType     string // which type of polymorphic loop is this? (oneOf, anyOf, allOf)
 	IsPolymorphicResult bool   // if this result comes from a polymorphic loop.
 	IsInfiniteLoop      bool   // if all the definitions in the reference loop are marked as required, this is an infinite circular reference, thus is not allowed.
 }

index/index_model.go

@@ -28,6 +28,7 @@ type Reference struct {
 	Name                  string
 	Node                  *yaml.Node
 	ParentNode            *yaml.Node
+	ParentNodeSchemaType  string // used to determine if the parent node is an array or not.
 	Resolved              bool
 	Circular              bool
 	Seen                  bool

resolver/resolver.go

@@ -42,6 +42,8 @@ type Resolver struct {
 	indexesVisited     int
 	journeysTaken      int
 	relativesSeen      int
+	ignorePoly         bool
+	ignoreArray        bool
 }
 
 // NewResolver will create a new resolver from a *index.SpecIndex
@@ -92,10 +94,21 @@ func (resolver *Resolver) GetNonPolymorphicCircularErrors() []*index.CircularRef
 			res = append(res, resolver.circularReferences[i])
 		}
 	}
-
 	return res
 }
 
+// IgnorePolymorphicCircularReferences will ignore any circular references that are polymorphic (oneOf, anyOf, allOf)
+// This must be set before any resolving is done.
+func (resolver *Resolver) IgnorePolymorphicCircularReferences() {
+	resolver.ignorePoly = true
+}
+
+// IgnoreArrayCircularReferences will ignore any circular references that stem from arrays. This must be set before
+// any resolving is done.
+func (resolver *Resolver) IgnoreArrayCircularReferences() {
+	resolver.ignoreArray = true
+}
+
 // GetJourneysTaken returns the number of journeys taken by the resolver
 func (resolver *Resolver) GetJourneysTaken() int {
 	return resolver.journeysTaken
@@ -231,7 +244,7 @@ func (resolver *Resolver) VisitReference(ref *index.Reference, seen map[string]b
 	}
 
 	journey = append(journey, ref)
-	relatives := resolver.extractRelatives(ref.Node, seen, journey, resolve)
+	relatives := resolver.extractRelatives(ref.Node, nil, seen, journey, resolve)
 
 	seen = make(map[string]bool)
 
@@ -254,11 +267,17 @@ func (resolver *Resolver) VisitReference(ref *index.Reference, seen map[string]b
 
 					visitedDefinitions := map[string]bool{}
 					isInfiniteLoop, _ := resolver.isInfiniteCircularDependency(foundDup, visitedDefinitions, nil)
+
+					isArray := false
+					if r.ParentNodeSchemaType == "array" {
+						isArray = true
+					}
 					circRef = &index.CircularReferenceResult{
 						Journey:        loop,
 						Start:          foundDup,
 						LoopIndex:      i,
 						LoopPoint:      foundDup,
+						IsArrayResult:  isArray,
 						IsInfiniteLoop: isInfiniteLoop,
 					}
 					resolver.circularReferences = append(resolver.circularReferences, circRef)
@@ -321,7 +340,7 @@ func (resolver *Resolver) isInfiniteCircularDependency(ref *index.Reference, vis
 	return false, visitedDefinitions
 }
 
-func (resolver *Resolver) extractRelatives(node *yaml.Node,
+func (resolver *Resolver) extractRelatives(node, parent *yaml.Node,
 	foundRelatives map[string]bool,
 	journey []*index.Reference, resolve bool) []*index.Reference {
 
@@ -333,7 +352,30 @@ func (resolver *Resolver) extractRelatives(node *yaml.Node,
 	if len(node.Content) > 0 {
 		for i, n := range node.Content {
 			if utils.IsNodeMap(n) || utils.IsNodeArray(n) {
-				found = append(found, resolver.extractRelatives(n, foundRelatives, journey, resolve)...)
+
+				var anyvn, allvn, onevn, arrayTypevn *yaml.Node
+
+				// extract polymorphic references
+				if len(n.Content) > 1 {
+					_, anyvn = utils.FindKeyNodeTop("anyOf", n.Content)
+					_, allvn = utils.FindKeyNodeTop("allOf", n.Content)
+					_, onevn = utils.FindKeyNodeTop("oneOf", n.Content)
+					_, arrayTypevn = utils.FindKeyNodeTop("type", n.Content)
+				}
+				if anyvn != nil || allvn != nil || onevn != nil {
+					if resolver.ignorePoly {
+						continue
+					}
+				}
+				if arrayTypevn != nil {
+					if arrayTypevn.Value == "array" {
+						if resolver.ignoreArray {
+							continue
+						}
+					}
+				}
+
+				found = append(found, resolver.extractRelatives(n, node, foundRelatives, journey, resolve)...)
 			}
 
 			if i%2 == 0 && n.Value == "$ref" {
@@ -357,10 +399,22 @@ func (resolver *Resolver) extractRelatives(node *yaml.Node,
 					continue
 				}
 
+				schemaType := ""
+				if parent != nil {
+					_, arrayTypevn := utils.FindKeyNodeTop("type", parent.Content)
+					if arrayTypevn != nil {
+						if arrayTypevn.Value == "array" {
+							schemaType = "array"
+						}
+					}
+				}
+
 				r := &index.Reference{
 					Definition:           value,
 					Name:                 value,
 					Node:                 node,
+					ParentNode:           parent,
+					ParentNodeSchemaType: schemaType,
 				}
 
 				found = append(found, r)
@@ -398,6 +452,7 @@ func (resolver *Resolver) extractRelatives(node *yaml.Node,
 												Start:               ref,
 												LoopIndex:           i,
 												LoopPoint:           ref,
+												PolymorphicType:     n.Value,
 												IsPolymorphicResult: true,
 											}
 
@@ -435,6 +490,7 @@ func (resolver *Resolver) extractRelatives(node *yaml.Node,
 												Start:               ref,
 												LoopIndex:           i,
 												LoopPoint:           ref,
+												PolymorphicType:     n.Value,
 												IsPolymorphicResult: true,
 											}
 
@@ -449,6 +505,7 @@ func (resolver *Resolver) extractRelatives(node *yaml.Node,
 					}
 					break
 				}
+
 			}
 		}
 	}

resolver/resolver_test.go

@@ -4,7 +4,6 @@ import (
 	"errors"
 	"fmt"
 	"io/ioutil"
-	"net/url"
 	"testing"
 
 	"github.com/pb33f/libopenapi/index"
@@ -63,22 +62,68 @@ func TestResolver_CheckForCircularReferences(t *testing.T) {
 	assert.NoError(t, err)
 }
 
-func TestResolver_CheckForCircularReferences_DigitalOcean(t *testing.T) {
+func TestResolver_CheckForCircularReferences_CatchArray(t *testing.T) {
-	circular, _ := ioutil.ReadFile("../test_specs/digitalocean.yaml")
+	circular := []byte(`openapi: 3.0.0
+components:
+  schemas:
+    ProductCategory:
+      type: "object"
+      properties:
+        name:
+          type: "string"
+        children:
+          type: "array"
+          items:
+            $ref: "#/components/schemas/ProductCategory"
+          description: "Array of sub-categories in the same format."
+      required:
+        - "name"
+        - "children"`)
 	var rootNode yaml.Node
 	yaml.Unmarshal(circular, &rootNode)
 
-	baseURL, _ := url.Parse("https://raw.githubusercontent.com/digitalocean/openapi/main/specification")
+	index := index.NewSpecIndex(&rootNode)
-
-	index := index.NewSpecIndexWithConfig(&rootNode, &index.SpecIndexConfig{
-		AllowRemoteLookup: true,
-		AllowFileLookup:   true,
-		BaseURL:           baseURL,
-	})
 
 	resolver := NewResolver(index)
 	assert.NotNil(t, resolver)
 
+	circ := resolver.CheckForCircularReferences()
+	assert.Len(t, circ, 1)
+	assert.Len(t, resolver.GetResolvingErrors(), 1) // infinite loop is a resolving error.
+	assert.Len(t, resolver.GetCircularErrors(), 1)
+	assert.True(t, resolver.GetCircularErrors()[0].IsArrayResult)
+
+	_, err := yaml.Marshal(resolver.resolvedRoot)
+	assert.NoError(t, err)
+}
+
+func TestResolver_CheckForCircularReferences_IgnoreArray(t *testing.T) {
+	circular := []byte(`openapi: 3.0.0
+components:
+  schemas:
+    ProductCategory:
+      type: "object"
+      properties:
+        name:
+          type: "string"
+        children:
+          type: "array"
+          items:
+            $ref: "#/components/schemas/ProductCategory"
+          description: "Array of sub-categories in the same format."
+      required:
+        - "name"
+        - "children"`)
+	var rootNode yaml.Node
+	yaml.Unmarshal(circular, &rootNode)
+
+	index := index.NewSpecIndex(&rootNode)
+
+	resolver := NewResolver(index)
+	assert.NotNil(t, resolver)
+
+	resolver.IgnoreArrayCircularReferences()
+
 	circ := resolver.CheckForCircularReferences()
 	assert.Len(t, circ, 0)
 	assert.Len(t, resolver.GetResolvingErrors(), 0)
@@ -88,6 +133,208 @@ func TestResolver_CheckForCircularReferences_DigitalOcean(t *testing.T) {
 	assert.NoError(t, err)
 }
 
+func TestResolver_CheckForCircularReferences_IgnorePoly_Any(t *testing.T) {
+	circular := []byte(`openapi: 3.0.0
+components:
+  schemas:
+    ProductCategory:
+      type: "object"
+      properties:
+        name:
+          type: "string"
+        children:
+          type: "object"
+          anyOf:
+            - $ref: "#/components/schemas/ProductCategory"
+          description: "Array of sub-categories in the same format."
+      required:
+        - "name"
+        - "children"`)
+	var rootNode yaml.Node
+	yaml.Unmarshal(circular, &rootNode)
+
+	index := index.NewSpecIndex(&rootNode)
+
+	resolver := NewResolver(index)
+	assert.NotNil(t, resolver)
+
+	resolver.IgnorePolymorphicCircularReferences()
+
+	circ := resolver.CheckForCircularReferences()
+	assert.Len(t, circ, 0)
+	assert.Len(t, resolver.GetResolvingErrors(), 0)
+	assert.Len(t, resolver.GetCircularErrors(), 0)
+
+	_, err := yaml.Marshal(resolver.resolvedRoot)
+	assert.NoError(t, err)
+}
+
+func TestResolver_CheckForCircularReferences_IgnorePoly_All(t *testing.T) {
+	circular := []byte(`openapi: 3.0.0
+components:
+  schemas:
+    ProductCategory:
+      type: "object"
+      properties:
+        name:
+          type: "string"
+        children:
+          type: "object"
+          allOf:
+            - $ref: "#/components/schemas/ProductCategory"
+          description: "Array of sub-categories in the same format."
+      required:
+        - "name"
+        - "children"`)
+	var rootNode yaml.Node
+	yaml.Unmarshal(circular, &rootNode)
+
+	index := index.NewSpecIndex(&rootNode)
+
+	resolver := NewResolver(index)
+	assert.NotNil(t, resolver)
+
+	resolver.IgnorePolymorphicCircularReferences()
+
+	circ := resolver.CheckForCircularReferences()
+	assert.Len(t, circ, 0)
+	assert.Len(t, resolver.GetResolvingErrors(), 0)
+	assert.Len(t, resolver.GetCircularErrors(), 0)
+
+	_, err := yaml.Marshal(resolver.resolvedRoot)
+	assert.NoError(t, err)
+}
+
+func TestResolver_CheckForCircularReferences_IgnorePoly_One(t *testing.T) {
+	circular := []byte(`openapi: 3.0.0
+components:
+  schemas:
+    ProductCategory:
+      type: "object"
+      properties:
+        name:
+          type: "string"
+        children:
+          type: "object"
+          oneOf:
+            - $ref: "#/components/schemas/ProductCategory"
+          description: "Array of sub-categories in the same format."
+      required:
+        - "name"
+        - "children"`)
+	var rootNode yaml.Node
+	yaml.Unmarshal(circular, &rootNode)
+
+	index := index.NewSpecIndex(&rootNode)
+
+	resolver := NewResolver(index)
+	assert.NotNil(t, resolver)
+
+	resolver.IgnorePolymorphicCircularReferences()
+
+	circ := resolver.CheckForCircularReferences()
+	assert.Len(t, circ, 0)
+	assert.Len(t, resolver.GetResolvingErrors(), 0)
+	assert.Len(t, resolver.GetCircularErrors(), 0)
+
+	_, err := yaml.Marshal(resolver.resolvedRoot)
+	assert.NoError(t, err)
+}
+
+func TestResolver_CheckForCircularReferences_CatchPoly_Any(t *testing.T) {
+	circular := []byte(`openapi: 3.0.0
+components:
+  schemas:
+    ProductCategory:
+      type: "object"
+      properties:
+        name:
+          type: "string"
+        children:
+          type: "object"
+          anyOf:
+            - $ref: "#/components/schemas/ProductCategory"
+          description: "Array of sub-categories in the same format."
+      required:
+        - "name"
+        - "children"`)
+	var rootNode yaml.Node
+	yaml.Unmarshal(circular, &rootNode)
+
+	index := index.NewSpecIndex(&rootNode)
+
+	resolver := NewResolver(index)
+	assert.NotNil(t, resolver)
+
+	circ := resolver.CheckForCircularReferences()
+	assert.Len(t, circ, 0)
+	assert.Len(t, resolver.GetResolvingErrors(), 0) // not an infinite loop if poly.
+	assert.Len(t, resolver.GetCircularErrors(), 1)
+	assert.Equal(t, "anyOf", resolver.GetCircularErrors()[0].PolymorphicType)
+	_, err := yaml.Marshal(resolver.resolvedRoot)
+	assert.NoError(t, err)
+}
+
+func TestResolver_CheckForCircularReferences_CatchPoly_All(t *testing.T) {
+	circular := []byte(`openapi: 3.0.0
+components:
+  schemas:
+    ProductCategory:
+      type: "object"
+      properties:
+        name:
+          type: "string"
+        children:
+          type: "object"
+          allOf:
+            - $ref: "#/components/schemas/ProductCategory"
+          description: "Array of sub-categories in the same format."
+      required:
+        - "name"
+        - "children"`)
+	var rootNode yaml.Node
+	yaml.Unmarshal(circular, &rootNode)
+
+	index := index.NewSpecIndex(&rootNode)
+
+	resolver := NewResolver(index)
+	assert.NotNil(t, resolver)
+
+	circ := resolver.CheckForCircularReferences()
+	assert.Len(t, circ, 0)
+	assert.Len(t, resolver.GetResolvingErrors(), 0) // not an infinite loop if poly.
+	assert.Len(t, resolver.GetCircularErrors(), 1)
+	assert.Equal(t, "allOf", resolver.GetCircularErrors()[0].PolymorphicType)
+	assert.True(t, resolver.GetCircularErrors()[0].IsPolymorphicResult)
+	_, err := yaml.Marshal(resolver.resolvedRoot)
+	assert.NoError(t, err)
+}
+
+//func TestResolver_CheckForCircularReferences_DigitalOcean(t *testing.T) {
+//	circular, _ := ioutil.ReadFile("../test_specs/digitalocean.yaml")
+//	var rootNode yaml.Node
+//	yaml.Unmarshal(circular, &rootNode)
+//
+//	baseURL, _ := url.Parse("https://raw.githubusercontent.com/digitalocean/openapi/main/specification")
+//
+//	index := index.NewSpecIndexWithConfig(&rootNode, &index.SpecIndexConfig{
+//		AllowRemoteLookup: true,
+//		AllowFileLookup:   true,
+//		BaseURL:           baseURL,
+//	})
+//
+//	resolver := NewResolver(index)
+//	assert.NotNil(t, resolver)
+//
+//	circ := resolver.CheckForCircularReferences()
+//	assert.Len(t, circ, 0)
+//	assert.Len(t, resolver.GetResolvingErrors(), 0)
+//	assert.Len(t, resolver.GetCircularErrors(), 0)
+//
+//	_, err := yaml.Marshal(resolver.resolvedRoot)
+//	assert.NoError(t, err)
+//}
+
 func TestResolver_CircularReferencesRequiredValid(t *testing.T) {
 	circular, _ := ioutil.ReadFile("../test_specs/swagger-valid-recursive-model.yaml")
 	var rootNode yaml.Node
@@ -129,7 +376,7 @@ func TestResolver_DeepJourney(t *testing.T) {
 	}
 	index := index.NewSpecIndex(nil)
 	resolver := NewResolver(index)
-	assert.Nil(t, resolver.extractRelatives(nil, nil, journey, false))
+	assert.Nil(t, resolver.extractRelatives(nil, nil, nil, journey, false))
 }
 
 func TestResolver_ResolveComponents_Stripe(t *testing.T) {

utils/utils.go

@@ -236,6 +236,9 @@ func FindKeyNodeTop(key string, nodes []*yaml.Node) (keyNode *yaml.Node, valueNo
 		}
 
 		if strings.EqualFold(key, v.Value) {
+			if i+1 >= len(nodes) {
+				return v, nodes[i]
+			}
 			return v, nodes[i+1] // next node is what we need.
 		}
 	}