fix: add support for conversion of ref in array schema (#8719)

Co-authored-by: Hunter Lovell <[email protected]>

Author: jnjacobson

.changeset/puny-poems-sink.md

@@ -0,0 +1,5 @@
+---
+"langchain": patch
+---
+
+add support for conversion of ref in array schema

langchain/src/chains/openai_functions/openapi.ts

@@ -193,9 +193,11 @@ export function convertOpenAPISchemaToJSONSchema(
     );
   }
   if (schema.type === "array") {
+    const openAPIItems = spec.getSchema(schema.items) ?? {};
+
     return {
       type: "array",
-      items: convertOpenAPISchemaToJSONSchema(schema.items ?? {}, spec),
+      items: convertOpenAPISchemaToJSONSchema(openAPIItems, spec),
       minItems: schema.minItems,
       maxItems: schema.maxItems,
     } as JsonSchema7ArrayType;

langchain/src/chains/openai_functions/tests/openapi.test.ts

@@ -69,6 +69,21 @@ test("Test convert OpenAPI params to JSON Schema", async () => {
                 },
               },
             },
+            {
+              name: "refParam",
+              in: "query",
+              schema: {
+                $ref: "#/components/schemas/RefObject",
+              },
+            },
+            {
+              name: "refArrayParam",
+              in: "query",
+              schema: {
+                type: "array",
+                items: { $ref: "#/components/schemas/RefObject" },
+              },
+            },
             {
               name: "nestedObjectInArrayParam",
               in: "query",
@@ -147,6 +162,21 @@ test("Test convert OpenAPI params to JSON Schema", async () => {
         },
       },
     },
+    components: {
+      schemas: {
+        RefObject: {
+          type: "object",
+          properties: {
+            foo: {
+              type: "string",
+            },
+            bar: {
+              type: "number",
+            },
+          },
+        },
+      },
+    },
   });
 
   const createWidget = spec.getOperation(
@@ -225,6 +255,26 @@ test("Test convert OpenAPI params to JSON Schema", async () => {
   expect(typedStringArrayParamSchema.items).not.toBeUndefined();
   expectType("string", typedStringArrayParamSchema.items);
 
+  const refParamSchema = convertOpenAPISchemaToJSONSchema(
+    getParamSchema(createWidget, "refParam"),
+    spec
+  );
+  const typedRefParamSchema = expectType("object", refParamSchema);
+  expectType("string", typedRefParamSchema.properties.foo);
+  expectType("number", typedRefParamSchema.properties.bar);
+
+  const refArrayParamSchema = convertOpenAPISchemaToJSONSchema(
+    getParamSchema(createWidget, "refArrayParam"),
+    spec
+  );
+  const typedRefArrayParamSchema = expectType("array", refArrayParamSchema);
+  const typedRefArrayParamSchemaItems = expectType(
+    "object",
+    typedRefArrayParamSchema.items
+  );
+  expectType("string", typedRefArrayParamSchemaItems.properties.foo);
+  expectType("number", typedRefArrayParamSchemaItems.properties.bar);
+
   const nestedObjectInArrayParamSchema = convertOpenAPISchemaToJSONSchema(
     getParamSchema(createWidget, "nestedObjectInArrayParam"),
     spec