From fbfe31dd8ce05aafea53b153d30661f54ccc7d4a Mon Sep 17 00:00:00 2001
From: Andrew Young <andrew.young@verizonmedia.com>
Date: Thu, 26 Jan 2023 13:42:47 -0800
Subject: [PATCH] Fix allOf merges using external refs

---
 pkg/codegen/codegen_test.go  |  5 ++++-
 pkg/codegen/filter_test.go   | 10 ++++++++--
 pkg/codegen/merge_schemas.go |  4 ++--
 pkg/codegen/test_schema.json | 15 +++++++++++++++
 pkg/codegen/test_spec.yaml   | 28 ++++++++++++++++++++++++++++
 5 files changed, 57 insertions(+), 5 deletions(-)
 create mode 100644 pkg/codegen/test_schema.json

diff --git a/pkg/codegen/codegen_test.go b/pkg/codegen/codegen_test.go
index e3878f58dd..6ae61211a9 100644
--- a/pkg/codegen/codegen_test.go
+++ b/pkg/codegen/codegen_test.go
@@ -145,8 +145,11 @@ func TestExampleOpenAPICodeGeneration(t *testing.T) {
 		},
 	}
 
+	loader := openapi3.NewLoader()
+	loader.IsExternalRefsAllowed = true
+
 	// Get a spec from the test definition in this file:
-	swagger, err := openapi3.NewLoader().LoadFromData([]byte(testOpenAPIDefinition))
+	swagger, err := loader.LoadFromData([]byte(testOpenAPIDefinition))
 	assert.NoError(t, err)
 
 	// Run our code generation:
diff --git a/pkg/codegen/filter_test.go b/pkg/codegen/filter_test.go
index d3a5aec546..774d016a84 100644
--- a/pkg/codegen/filter_test.go
+++ b/pkg/codegen/filter_test.go
@@ -23,8 +23,11 @@ func TestFilterOperationsByTag(t *testing.T) {
 			},
 		}
 
+		loader := openapi3.NewLoader()
+		loader.IsExternalRefsAllowed = true
+
 		// Get a spec from the test definition in this file:
-		swagger, err := openapi3.NewLoader().LoadFromData([]byte(testOpenAPIDefinition))
+		swagger, err := loader.LoadFromData([]byte(testOpenAPIDefinition))
 		assert.NoError(t, err)
 
 		// Run our code generation:
@@ -49,8 +52,11 @@ func TestFilterOperationsByTag(t *testing.T) {
 			},
 		}
 
+		loader := openapi3.NewLoader()
+		loader.IsExternalRefsAllowed = true
+
 		// Get a spec from the test definition in this file:
-		swagger, err := openapi3.NewLoader().LoadFromData([]byte(testOpenAPIDefinition))
+		swagger, err := loader.LoadFromData([]byte(testOpenAPIDefinition))
 		assert.NoError(t, err)
 
 		// Run our code generation:
diff --git a/pkg/codegen/merge_schemas.go b/pkg/codegen/merge_schemas.go
index 466e55c549..8cfbe13a00 100644
--- a/pkg/codegen/merge_schemas.go
+++ b/pkg/codegen/merge_schemas.go
@@ -53,10 +53,10 @@ func valueWithPropagatedRef(ref *openapi3.SchemaRef) (openapi3.Schema, error) {
 	}
 
 	pathParts := strings.Split(ref.Ref, "#")
-	if len(pathParts) != 2 {
+	if len(pathParts) < 1 || len(pathParts) > 2 {
 		return openapi3.Schema{}, fmt.Errorf("unsupported reference: %s", ref.Ref)
 	}
-	remoteComponent, _ := pathParts[0], pathParts[1]
+	remoteComponent := pathParts[0]
 
 	// remote ref
 	schema := *ref.Value
diff --git a/pkg/codegen/test_schema.json b/pkg/codegen/test_schema.json
new file mode 100644
index 0000000000..d64939498e
--- /dev/null
+++ b/pkg/codegen/test_schema.json
@@ -0,0 +1,15 @@
+{
+  "title": "node",
+  "type": "object",
+  "description": "Represents a node",
+  "properties": {
+    "id": {
+      "type": "string",
+      "format": "uri-reference"
+    },
+    "type": {
+      "type": "string",
+      "pattern": "^[A-Z][a-zA-Z0-9]*$"
+    }
+  }
+}
\ No newline at end of file
diff --git a/pkg/codegen/test_spec.yaml b/pkg/codegen/test_spec.yaml
index 7491c69c31..b50f7491c5 100644
--- a/pkg/codegen/test_spec.yaml
+++ b/pkg/codegen/test_spec.yaml
@@ -108,6 +108,25 @@ paths:
             application/json:
               schema:
                 $ref: '#/components/schemas/Error'
+  /user:
+    get:
+      tags:
+        - mergeAllOf
+      summary: Merges allOf ref-ing a JSON schema
+      operationId: getUser
+      responses:
+        200:
+          description: Success
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/User'
+        default:
+          description: Error
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Error'
 
 components:
   schemas:
@@ -177,3 +196,12 @@ components:
             - na
             - single
             - double
+    User:
+      allOf:
+        - $ref: ./test_schema.json
+        - type: object
+          additionalProperties: false
+          properties:
+            name:
+              type: string
+              description: User name