fix(Paths): Solve circular references

lib/open-api-mocker.js

@@ -1,6 +1,6 @@
 'use strict';
 
-const jsonRefs = require('json-refs');
+const SwaggerParser = require('@apidevtools/swagger-parser');
 
 const { Parser: OpenApiParser } = require('./openapi');
 const { Parser: ServersParser } = require('./servers');
@@ -10,6 +10,7 @@ const OpenAPISchemaInvalid = require('./errors/openapi-schema-invalid-error');
 
 const optionsBuilder = require('./utils/options-builder');
 const ExplicitSchemaLoader = require('./schema-loaders/explicit-loader');
+const replaceCircularReferencesFromObject = require('./utils/replace-circular-references-from-object');
 
 class OpenApiMocker {
 
@@ -41,16 +42,17 @@ class OpenApiMocker {
 			this.schema = await this.schema;
 
 		try {
-			const parsedSchemas = await jsonRefs.resolveRefs(this.schema);
-
-			this.schema = parsedSchemas.resolved;
+			this.schema = await SwaggerParser.validate(this.schema);
 
 			const openApiParser = new OpenApiParser();
 			const openapi = openApiParser.parse(this.schema);
 
 			const serversParser = new ServersParser();
 			const servers = serversParser.parse(this.schema);
 
+			const defaultValue = {'type' : 'string'}
+			this.schema = replaceCircularReferencesFromObject(this.schema, defaultValue, 3);
+
 			const pathsParser = new PathsParser();
 			const paths = pathsParser.parse(this.schema);
 

lib/utils/replace-circular-references-from-object.js

@@ -0,0 +1,78 @@
+/**
+ * Returns the given object without circular references.
+ * Replaces circular references with the given default value if the number of circular references exceeds the given depth limit.
+ * @param {Object} obj - The object to remove circular references from.
+ * @param {*} defaultValue - The default value to use for replacing circular references.
+ * @param {number} depthLimit - The maximum number of circular references allowed before using the default value.
+ * @returns {Object} - The object without circular references.
+ */
+function replaceCircularReferencesFromObject(obj, defaultValue, depthLimit) {
+  const circularReferenceReplacer = new CircularReferenceReplacer(defaultValue, depthLimit);
+  const objWithoutCircularReferences = circularReferenceReplacer.replace(obj);
+  return objWithoutCircularReferences;
+}
+
+class CircularReferenceReplacer {
+  #depthLimit;
+  #defaultValue;
+
+  /**
+   * @param {*} defaultValue - The default value to use for replacing circular references.
+   * @param {number} depthLimit - The maximum number of circular references allowed before using the default value.
+   */
+  constructor(defaultValue, depthLimit) {
+    this.#depthLimit = depthLimit;
+    this.#defaultValue = defaultValue;
+  }
+
+  replace(obj) {
+    return this.#replaceRecursively(obj, []);
+  }
+
+  #replaceRecursively(obj, ancestors) {
+    if (!this.#isJSONObjectOrArray(obj)) {
+      return obj;
+    }
+    if (this.#hasCircularReferences(obj, ancestors) && this.#exceedsDepthLimit(obj, ancestors)) {
+      return this.#defaultValue;
+    }
+    ancestors.push(obj); // push the original reference
+    obj = Array.isArray(obj) ? [...obj] : { ...obj };
+    for (let key in obj) {
+      obj[key] = this.#replaceRecursively(
+        obj[key],
+        [...ancestors] // copy of ancestors avoiding mutation by siblings
+      );
+    }
+    return obj;
+  }
+
+  #hasCircularReferences(obj, ancestors) {
+    const hasCircularReferences = ancestors.includes(obj);
+    return hasCircularReferences;
+  }
+
+  #exceedsDepthLimit(obj, ancestors) {
+    const exceedsCircularReferencesLimit = this.#countOccurrences(obj, ancestors) >= this.#depthLimit;
+    return exceedsCircularReferencesLimit;
+  }
+
+  #countOccurrences(value, array) {
+    const count = array.reduce((accumulator, currentValue) => (currentValue === value ? accumulator + 1 : accumulator), 0);
+    return count;
+  }
+
+  #isJSONObjectOrArray(obj) {
+    return (
+      typeof obj === 'object' &&
+      obj !== null &&
+      !(obj instanceof Boolean) &&
+      !(obj instanceof Date) &&
+      !(obj instanceof Number) &&
+      !(obj instanceof RegExp) &&
+      !(obj instanceof String)
+    );
+  }
+}
+
+module.exports = replaceCircularReferencesFromObject;

package.json

@@ -38,6 +38,7 @@
     "sinon": "^15.1.0"
   },
   "dependencies": {
+    "@apidevtools/swagger-parser": "^10.1.0",
     "@faker-js/faker": "^8.0.2",
     "ajv": "^6.12.6",
     "ajv-openapi": "^2.0.0",
@@ -48,7 +49,6 @@
     "cors": "^2.8.5",
     "express": "^4.18.2",
     "js-yaml": "^4.1.0",
-    "json-refs": "^3.0.15",
     "lllog": "^1.1.2",
     "micro-memoize": "^4.1.2",
     "parse-prefer-header": "^1.0.0",