fix: pass default value to output header function

mrlubos · mrlubos · commit c076e4d3e969 · 2026-03-15T04:46:07.000+01:00
diff --git a/.changeset/brown-owls-flow.md b/.changeset/brown-owls-flow.md
@@ -0,0 +1,5 @@
+---
+"@hey-api/shared": patch
+---
+
+**utils**: `outputHeaderToPrefix()` function signature change
diff --git a/.changeset/weak-onions-flash.md b/.changeset/weak-onions-flash.md
@@ -0,0 +1,5 @@
+---
+"@hey-api/openapi-ts": patch
+---
+
+**output**: pass default value to `header` function
diff --git a/packages/openapi-python/src/config/output/config.ts b/packages/openapi-python/src/config/output/config.ts
@@ -24,7 +24,6 @@ export function getOutput(userConfig: { output: MaybeArray<string | UserOutput>
         name: '{{name}}',
         suffix: '_gen',
       },
-      header: '# This file is auto-generated by @hey-api/openapi-python',
       path: '',
       postProcess: [],
       preferExportAll: false,
diff --git a/packages/openapi-python/src/createClient.ts b/packages/openapi-python/src/createClient.ts
@@ -107,6 +107,7 @@ export async function createClient({
     eventInputPatch.timeEnd();
 
     const eventParser = logger.timeEvent('parser');
+    const header = config.output.header;
     // TODO: allow overriding via config
     const project = new Project({
       defaultFileName: '__init__',
@@ -125,7 +126,11 @@ export async function createClient({
         : undefined,
       renderers: [
         new PythonRenderer({
-          header: config.output.header,
+          header: (ctx) => {
+            const defaultValue = ['# This file is auto-generated by @hey-api/openapi-python'];
+            const result = typeof header === 'function' ? header({ ...ctx, defaultValue }) : header;
+            return result === undefined ? defaultValue : result;
+          },
           preferExportAll: config.output.preferExportAll,
           preferFileExtension: config.output.importFileExtension || undefined,
           resolveModuleName: config.output.resolveModuleName,
diff --git a/packages/openapi-python/src/generate/client.ts b/packages/openapi-python/src/generate/client.ts
@@ -154,7 +154,11 @@ export function generateClientBundle({
   project: IProject;
 }): Map<string, string> | undefined {
   const renamed = new Map<string, string>();
-  const headerPrefix = outputHeaderToPrefix(header, project);
+  const headerPrefix = outputHeaderToPrefix({
+    defaultValue: ['# This file is auto-generated by @hey-api/openapi-python'],
+    header,
+    project,
+  });
 
   // copy Hey API clients to output
   const isHeyApiClientPlugin = plugin.name.startsWith('@hey-api/client-');
diff --git a/packages/openapi-python/src/py-dsl/utils/render.ts b/packages/openapi-python/src/py-dsl/utils/render.ts
@@ -11,6 +11,7 @@ type ExportsOptions = {
   preferExportAll?: boolean;
 };
 type Header = MaybeArray<string> | null | undefined;
+type HeaderArg = MaybeFunc<(ctx: RenderContext<PyDsl>) => Header>;
 type Imports = Array<ReadonlyArray<ModuleImport>>;
 
 function headerToLines(header: Header): ReadonlyArray<string> {
@@ -32,7 +33,7 @@ export class PythonRenderer implements Renderer {
    *
    * @private
    */
-  private _header?: MaybeFunc<(ctx: RenderContext<PyDsl>) => Header>;
+  private _header?: HeaderArg;
   /**
    * Whether `export * from 'module'` should be used when possible instead of named exports.
    *
@@ -54,7 +55,7 @@ export class PythonRenderer implements Renderer {
 
   constructor(
     args: {
-      header?: MaybeFunc<(ctx: RenderContext<PyDsl>) => Header>;
+      header?: HeaderArg;
       preferExportAll?: boolean;
       preferFileExtension?: string;
       resolveModuleName?: (moduleName: string) => string | undefined;
diff --git a/packages/openapi-ts/src/config/output/config.ts b/packages/openapi-ts/src/config/output/config.ts
@@ -36,7 +36,6 @@ export function getOutput(userConfig: { output: MaybeArray<string | UserOutput>
         suffix: '.gen',
       },
       format: null,
-      header: '// This file is auto-generated by @hey-api/openapi-ts',
       lint: null,
       path: '',
       postProcess: [],
diff --git a/packages/openapi-ts/src/createClient.ts b/packages/openapi-ts/src/createClient.ts
@@ -107,6 +107,7 @@ export async function createClient({
     eventInputPatch.timeEnd();
 
     const eventParser = logger.timeEvent('parser');
+    const header = config.output.header;
     // TODO: allow overriding via config
     const project = new Project({
       defaultFileName: 'index',
@@ -125,7 +126,11 @@ export async function createClient({
         : undefined,
       renderers: [
         new TypeScriptRenderer({
-          header: config.output.header,
+          header: (ctx) => {
+            const defaultValue = ['// This file is auto-generated by @hey-api/openapi-ts'];
+            const result = typeof header === 'function' ? header({ ...ctx, defaultValue }) : header;
+            return result === undefined ? defaultValue : result;
+          },
           preferExportAll: config.output.preferExportAll,
           preferFileExtension: config.output.importFileExtension || undefined,
           resolveModuleName: config.output.resolveModuleName,
diff --git a/packages/openapi-ts/src/generate/client.ts b/packages/openapi-ts/src/generate/client.ts
@@ -157,7 +157,11 @@ export function generateClientBundle({
   project: IProject;
 }): Map<string, string> | undefined {
   const renamed = new Map<string, string>();
-  const headerPrefix = outputHeaderToPrefix(header, project);
+  const headerPrefix = outputHeaderToPrefix({
+    defaultValue: ['// This file is auto-generated by @hey-api/openapi-ts'],
+    header,
+    project,
+  });
 
   // copy Hey API clients to output
   const isHeyApiClientPlugin = plugin.name.startsWith('@hey-api/client-');
diff --git a/packages/openapi-ts/src/ts-dsl/utils/render.ts b/packages/openapi-ts/src/ts-dsl/utils/render.ts
@@ -12,6 +12,7 @@ type ExportsOptions = {
   preferExportAll?: boolean;
 };
 type Header = MaybeArray<string> | null | undefined;
+type HeaderArg = MaybeFunc<(ctx: RenderContext<TsDsl>) => Header>;
 type Imports = ReadonlyArray<ReadonlyArray<ModuleImport>>;
 
 function headerToLines(header: Header): ReadonlyArray<string> {
@@ -33,7 +34,7 @@ export class TypeScriptRenderer implements Renderer {
    *
    * @private
    */
-  private _header?: MaybeFunc<(ctx: RenderContext<TsDsl>) => Header>;
+  private _header?: HeaderArg;
   /**
    * Whether `export * from 'module'` should be used when possible instead of named exports.
    *
@@ -55,7 +56,7 @@ export class TypeScriptRenderer implements Renderer {
 
   constructor(
     args: {
-      header?: MaybeFunc<(ctx: RenderContext<TsDsl>) => Header>;
+      header?: HeaderArg;
       preferExportAll?: boolean;
       preferFileExtension?: string;
       resolveModuleName?: (moduleName: string) => string | undefined;
diff --git a/packages/shared/src/config/output/types.ts b/packages/shared/src/config/output/types.ts
@@ -3,6 +3,10 @@ import type { MaybeArray, MaybeFunc } from '@hey-api/types';
 
 export type OutputHeader = MaybeFunc<
   (
-    ctx: Omit<RenderContext, 'file'> & Pick<Partial<RenderContext>, 'file'>,
+    ctx: Pick<RenderContext, 'meta' | 'project'> &
+      Pick<Partial<RenderContext>, 'file'> & {
+        /** The default header value. */
+        defaultValue: ReadonlyArray<string>;
+      },
   ) => MaybeArray<string> | null | undefined
 >;
diff --git a/packages/shared/src/utils/header.ts b/packages/shared/src/utils/header.ts
@@ -5,9 +5,15 @@ import type { OutputHeader } from '../config/output/types';
 /**
  * Converts an {@link OutputHeader} value to a string prefix for file content.
  */
-export function outputHeaderToPrefix(header: OutputHeader, project: IProject): string {
-  let lines = typeof header === 'function' ? header({ project }) : header;
-  if (lines === null || lines === undefined) return '';
+export function outputHeaderToPrefix(ctx: {
+  defaultValue: ReadonlyArray<string>;
+  header: OutputHeader;
+  project: IProject;
+}): string {
+  const { defaultValue, header, project } = ctx;
+  let lines = typeof header === 'function' ? header({ defaultValue, project }) : header;
+  if (lines === undefined) lines = defaultValue;
+  if (lines === null) return '';
   lines =
     typeof lines === 'string' ? lines.split(/\r?\n/) : lines.flatMap((line) => line.split(/\r?\n/));
   const content = lines.join('\n');

-Original file line number
+Diff line change
@@ @@ -0,0 +1,5 @@ @@
 +---
 +"@hey-api/shared": patch
 +---
++
 +**utils**: `outputHeaderToPrefix()` function signature change