fix(openapi): handle when custom config for filename is optional (#4750)

generators/openapi/src/customConfig.ts

@@ -3,7 +3,7 @@ import { GeneratorConfig } from "@fern-api/generator-commons";
 export interface FernOpenapiCustomConfig {
     format: "yaml" | "json";
     customOverrides: Record<string, unknown>;
-    filename: string;
+    filename?: string;
 }
 
 const DEFAULT_FERN_OPENAPI_CUSTOM_CONFIG: FernOpenapiCustomConfig = {

generators/openapi/src/writeOpenApi.ts

@@ -1,14 +1,12 @@
 import { IntermediateRepresentation } from "@fern-fern/ir-sdk/api";
 import * as IrSerialization from "@fern-fern/ir-sdk/serialization";
-import { readFile, writeFile } from "fs/promises";
+import { writeFile } from "fs/promises";
 import yaml from "js-yaml";
-import merge from "lodash-es/merge";
 import path from "path";
 import { convertToOpenApi } from "./convertToOpenApi";
 import { getCustomConfig } from "./customConfig";
 import {
     GeneratorNotificationService,
-    GeneratorExecParsing,
     GeneratorUpdate,
     ExitStatusUpdate,
     parseGeneratorConfig,
@@ -41,28 +39,37 @@ export async function writeOpenApi(mode: Mode, pathToConfig: string): Promise<vo
                 ir,
                 mode
             });
+            // eslint-disable-next-line no-console
+            console.log(`openapi before override ${JSON.stringify(openapi)}`);
 
             if (customConfig.customOverrides != null) {
                 openapi = await mergeWithOverrides({
                     data: openapi,
                     overrides: customConfig.customOverrides
                 });
+                // eslint-disable-next-line no-console
+                console.log(`openapi after override ${JSON.stringify(openapi)}`);
             }
 
+            let filename: string = customConfig.filename ?? "openapi.yml";
             if (customConfig.format === "json") {
-                await writeFile(
-                    path.join(config.output.path, replaceExtension(customConfig.filename, "json")),
-                    JSON.stringify(openapi, undefined, 2)
-                );
+                filename = path.join(config.output.path, replaceExtension(filename, "json"));
+                await writeFile(filename, JSON.stringify(openapi, undefined, 2));
             } else {
-                const filename =
-                    customConfig.filename.endsWith("yml") || customConfig.filename.endsWith("yaml")
-                        ? customConfig.filename
-                        : replaceExtension(customConfig.filename, "yml");
+                filename =
+                    filename.endsWith("yml") || filename.endsWith("yaml")
+                        ? filename
+                        : replaceExtension(filename, "yml");
                 await writeFile(path.join(config.output.path, filename), yaml.dump(openapi));
             }
             await generatorLoggingClient.sendUpdate(GeneratorUpdate.exitStatusUpdate(ExitStatusUpdate.successful({})));
         } catch (e) {
+            if (e instanceof Error) {
+                // eslint-disable-next-line no-console
+                console.log((e as Error)?.message);
+                // eslint-disable-next-line no-console
+                console.log((e as Error)?.stack);
+            }
             await generatorLoggingClient.sendUpdate(
                 GeneratorUpdate.exitStatusUpdate(
                     ExitStatusUpdate.error({

generators/openapi/versions.yml

@@ -1,3 +1,12 @@
+- version: 0.1.4
+  createdAt: '2024-09-25'
+  changelogEntry:
+    - type: fix
+      summary: | 
+        The generator now handles `config.filename` being null so that the 
+        configuration for the generator can continue to be backwards compatible. 
+  irVersion: 53
+
 - version: 0.1.3
   createdAt: '2024-09-25'
   changelogEntry: