fix(validation): handle anyOf/oneOf schemas in required parameter validation

src/core/utils/index.js

@@ -612,6 +612,17 @@ export const validateParam = (param, value, { isOAS3 = false, bypassRequiredChec
     parameterContentMediaType
   } = getParameterSchema(param, { isOAS3 })
 
+  // Compose anyOf/oneOf schemas: if the schema lacks a direct type but has
+  // anyOf or oneOf, derive the type from the first sub-schema so that
+  // type-specific validation applies correctly.
+  if (paramDetails && !paramDetails.get("type")) {
+    const firstCompositeType =
+      paramDetails.getIn(["anyOf", 0, "type"]) || paramDetails.getIn(["oneOf", 0, "type"])
+    if (firstCompositeType) {
+      paramDetails = paramDetails.set("type", firstCompositeType)
+    }
+  }
+
   return validateValueBySchema(value, paramDetails, paramRequired, bypassRequiredCheck, parameterContentMediaType, isOAS3)
 }
 

test/unit/core/utils.js

@@ -1061,6 +1061,75 @@ describe("utils", () => {
       value = undefined
       assertValidateParam(param, value, ["Required field is not provided"])
     })
+
+    it("validates required OAS3 parameters with anyOf schema", () => {
+      // missing value with anyOf should report required error
+      param = {
+        required: true,
+        schema: {
+          anyOf: [
+            { type: "integer" },
+            { type: "string" }
+          ]
+        }
+      }
+      value = undefined
+      assertValidateOas3Param(param, value, ["Required field is not provided"])
+
+      // valid integer value with anyOf
+      param = {
+        required: true,
+        schema: {
+          anyOf: [
+            { type: "integer" },
+            { type: "string" }
+          ]
+        }
+      }
+      value = 123
+      assertValidateOas3Param(param, value, [])
+
+      // valid string value with anyOf (matches second sub-schema type via first)
+      param = {
+        required: true,
+        schema: {
+          anyOf: [
+            { type: "string" },
+            { type: "integer" }
+          ]
+        }
+      }
+      value = "hello"
+      assertValidateOas3Param(param, value, [])
+    })
+
+    it("validates required OAS3 parameters with oneOf schema", () => {
+      // missing value with oneOf should report required error
+      param = {
+        required: true,
+        schema: {
+          oneOf: [
+            { type: "integer" },
+            { type: "string" }
+          ]
+        }
+      }
+      value = undefined
+      assertValidateOas3Param(param, value, ["Required field is not provided"])
+
+      // valid integer value with oneOf
+      param = {
+        required: true,
+        schema: {
+          oneOf: [
+            { type: "integer" },
+            { type: "string" }
+          ]
+        }
+      }
+      value = 123
+      assertValidateOas3Param(param, value, [])
+    })
   })
 
   describe("fromJSOrdered", () => {