hey-api · mrlubos · Aug 22, 2025 · Aug 22, 2025 · Aug 22, 2025
diff --git a/.changeset/brown-pandas-stare.md b/.changeset/brown-pandas-stare.md
@@ -0,0 +1,5 @@
+---
+'@hey-api/openapi-ts': minor
+---
+
+feat(client): add support for server-sent events (SSE)
diff --git a/docs/openapi-ts/migrating.md b/docs/openapi-ts/migrating.md
@@ -7,6 +7,28 @@ description: Migrating to @hey-api/openapi-ts.
 
 While we try to avoid breaking changes, sometimes it's unavoidable in order to offer you the latest features. This page lists changes that require updates to your code. If you run into a problem with migration, please [open an issue](https://github.com/hey-api/openapi-ts/issues).
 
+## v0.81.0
+
+### Server-Sent Events (SSE)
+
+This release adds support for server-sent events (SSE). Instead of treating `text/event-stream` content types as regular HTTP methods, we now generate SSE streams. In practice, you will want to update your affected endpoints to process streamed events.
+
+::: code-group
+
+```js [before]
+const { data } = await foo();
+console.log(data.type);
+```
+
+```js [after]
+const { stream } = await foo();
+for await (const event of stream) {
+  console.log(event.type);
+}
+```
+
+:::
+
 ## v0.80.0
 
 ### Added Zod 4 and Zod Mini

diff --git a/packages/openapi-ts-tests/main/test/3.1.x.test.ts b/packages/openapi-ts-tests/main/test/3.1.x.test.ts
@@ -815,6 +815,81 @@ describe(`OpenAPI ${version}`, () => {
       description:
         'generates validator schemas for all integer format combinations (number/integer/string types with int8, int16, int32, int64, uint8, uint16, uint32, uint64 formats)',
     },
+    {
+      config: createConfig({
+        input: 'opencode.yaml',
+        output: 'sse-angular',
+        parser: {
+          filters: {
+            operations: {
+              include: ['GET /event'],
+            },
+          },
+        },
+        plugins: ['@hey-api/client-angular', '@hey-api/sdk'],
+      }),
+      description: 'client with SSE (Angular)',
+    },
+    {
+      config: createConfig({
+        input: 'opencode.yaml',
+        output: 'sse-axios',
+        parser: {
+          filters: {
+            operations: {
+              include: ['GET /event'],
+            },
+          },
+        },
+        plugins: ['@hey-api/client-axios', '@hey-api/sdk'],
+      }),
+      description: 'client with SSE (Axios)',
+    },
+    {
+      config: createConfig({
+        input: 'opencode.yaml',
+        output: 'sse-fetch',
+        parser: {
+          filters: {
+            operations: {
+              include: ['GET /event'],
+            },
+          },
+        },
+        plugins: ['@hey-api/client-fetch', '@hey-api/sdk'],
+      }),
+      description: 'client with SSE (Fetch)',
+    },
+    {
+      config: createConfig({
+        input: 'opencode.yaml',
+        output: 'sse-next',
+        parser: {
+          filters: {
+            operations: {
+              include: ['GET /event'],
+            },
+          },
+        },
+        plugins: ['@hey-api/client-next', '@hey-api/sdk'],
+      }),
+      description: 'client with SSE (Next.js)',
+    },
+    {
+      config: createConfig({
+        input: 'opencode.yaml',
+        output: 'sse-nuxt',
+        parser: {
+          filters: {
+            operations: {
+              include: ['GET /event'],
+            },
+          },
+        },
+        plugins: ['@hey-api/client-nuxt', '@hey-api/sdk'],
+      }),
+      description: 'client with SSE (Nuxt)',
+    },
   ];
 
   it.each(scenarios)('$description', async ({ config }) => {

diff --git a/...napi-ts-tests/main/test/__snapshots__/2.0.x/body-response-text-plain/client/client.gen.ts b/...napi-ts-tests/main/test/__snapshots__/2.0.x/body-response-text-plain/client/client.gen.ts
@@ -1,6 +1,12 @@
 // This file is auto-generated by @hey-api/openapi-ts
 
-import type { Client, Config, ResolvedRequestOptions } from './types.gen';
+import { createSseClient } from '../core/serverSentEvents.gen';
+import type {
+  Client,
+  Config,
+  RequestOptions,
+  ResolvedRequestOptions,
+} from './types.gen';
 import {
   buildUrl,
   createConfig,
@@ -33,7 +39,7 @@ export const createClient = (config: Config = {}): Client => {
     ResolvedRequestOptions
   >();
 
-  const request: Client['request'] = async (options) => {
+  const beforeRequest = async (options: RequestOptions) => {
     const opts = {
       ..._config,
       ...options,
@@ -63,6 +69,13 @@ export const createClient = (config: Config = {}): Client => {
     }
 
     const url = buildUrl(opts);
+
+    return { opts, url };
+  };
+
+  const request: Client['request'] = async (options) => {
+    // @ts-expect-error
+    const { opts, url } = await beforeRequest(options);
     const requestInit: ReqInit = {
       redirect: 'follow',
       ...opts,
@@ -180,20 +193,35 @@ export const createClient = (config: Config = {}): Client => {
         };
   };
 
+  const makeMethod = (method: Required<Config>['method']) => {
+    const fn = (options: RequestOptions) => request({ ...options, method });
+    fn.sse = async (options: RequestOptions) => {
+      const { opts, url } = await beforeRequest(options);
+      return createSseClient({
+        ...opts,
+        body: opts.body as BodyInit | null | undefined,
+        headers: opts.headers as unknown as Record<string, string>,
+        method,
+        url,
+      });
+    };
+    return fn;
+  };
+
   return {
     buildUrl,
-    connect: (options) => request({ ...options, method: 'CONNECT' }),
-    delete: (options) => request({ ...options, method: 'DELETE' }),
-    get: (options) => request({ ...options, method: 'GET' }),
+    connect: makeMethod('CONNECT'),
+    delete: makeMethod('DELETE'),
+    get: makeMethod('GET'),
     getConfig,
-    head: (options) => request({ ...options, method: 'HEAD' }),
+    head: makeMethod('HEAD'),
     interceptors,
-    options: (options) => request({ ...options, method: 'OPTIONS' }),
-    patch: (options) => request({ ...options, method: 'PATCH' }),
-    post: (options) => request({ ...options, method: 'POST' }),
-    put: (options) => request({ ...options, method: 'PUT' }),
+    options: makeMethod('OPTIONS'),
+    patch: makeMethod('PATCH'),
+    post: makeMethod('POST'),
+    put: makeMethod('PUT'),
     request,
     setConfig,
-    trace: (options) => request({ ...options, method: 'TRACE' }),
-  };
+    trace: makeMethod('TRACE'),
+  } as Client;
 };
diff --git a/...enapi-ts-tests/main/test/__snapshots__/2.0.x/body-response-text-plain/client/types.gen.ts b/...enapi-ts-tests/main/test/__snapshots__/2.0.x/body-response-text-plain/client/types.gen.ts
@@ -1,6 +1,10 @@
 // This file is auto-generated by @hey-api/openapi-ts
 
 import type { Auth } from '../core/auth.gen';
+import type {
+  ServerSentEventsOptions,
+  ServerSentEventsResult,
+} from '../core/serverSentEvents.gen';
 import type {
   Client as CoreClient,
   Config as CoreConfig,
@@ -61,13 +65,22 @@ export interface Config<T extends ClientOptions = ClientOptions>
 }
 
 export interface RequestOptions<
+  TData = unknown,
   TResponseStyle extends ResponseStyle = 'fields',
   ThrowOnError extends boolean = boolean,
   Url extends string = string,
 > extends Config<{
-    responseStyle: TResponseStyle;
-    throwOnError: ThrowOnError;
-  }> {
+      responseStyle: TResponseStyle;
+      throwOnError: ThrowOnError;
+    }>,
+    Pick<
+      ServerSentEventsOptions<TData>,
+      | 'onSseError'
+      | 'onSseEvent'
+      | 'sseDefaultRetryDelay'
+      | 'sseMaxRetryAttempts'
+      | 'sseMaxRetryDelay'
+    > {
   /**
    * Any body that you want to add to your request.
    *
@@ -87,7 +100,7 @@ export interface ResolvedRequestOptions<
   TResponseStyle extends ResponseStyle = 'fields',
   ThrowOnError extends boolean = boolean,
   Url extends string = string,
-> extends RequestOptions<TResponseStyle, ThrowOnError, Url> {
+> extends RequestOptions<unknown, TResponseStyle, ThrowOnError, Url> {
   serializedBody?: string;
 }
 
@@ -142,23 +155,39 @@ export interface ClientOptions {
   throwOnError?: boolean;
 }
 
-type MethodFn = <
+type MethodFnBase = <
   TData = unknown,
   TError = unknown,
   ThrowOnError extends boolean = false,
   TResponseStyle extends ResponseStyle = 'fields',
 >(
-  options: Omit<RequestOptions<TResponseStyle, ThrowOnError>, 'method'>,
+  options: Omit<RequestOptions<TData, TResponseStyle, ThrowOnError>, 'method'>,
 ) => RequestResult<TData, TError, ThrowOnError, TResponseStyle>;
 
+type MethodFnServerSentEvents = <
+  TData = unknown,
+  TError = unknown,
+  ThrowOnError extends boolean = false,
+  TResponseStyle extends ResponseStyle = 'fields',
+>(
+  options: Omit<RequestOptions<TData, TResponseStyle, ThrowOnError>, 'method'>,
+) => Promise<ServerSentEventsResult<TData, TError>>;
+
+type MethodFn = MethodFnBase & {
+  sse: MethodFnServerSentEvents;
+};
+
 type RequestFn = <
   TData = unknown,
   TError = unknown,
   ThrowOnError extends boolean = false,
   TResponseStyle extends ResponseStyle = 'fields',
 >(
-  options: Omit<RequestOptions<TResponseStyle, ThrowOnError>, 'method'> &
-    Pick<Required<RequestOptions<TResponseStyle, ThrowOnError>>, 'method'>,
+  options: Omit<RequestOptions<TData, TResponseStyle, ThrowOnError>, 'method'> &
+    Pick<
+      Required<RequestOptions<TData, TResponseStyle, ThrowOnError>>,
+      'method'
+    >,
 ) => RequestResult<TData, TError, ThrowOnError, TResponseStyle>;
 
 type BuildUrlFn = <
@@ -201,9 +230,10 @@ type OmitKeys<T, K> = Pick<T, Exclude<keyof T, K>>;
 export type Options<
   TData extends TDataShape = TDataShape,
   ThrowOnError extends boolean = boolean,
+  TResponse = unknown,
   TResponseStyle extends ResponseStyle = 'fields',
 > = OmitKeys<
-  RequestOptions<TResponseStyle, ThrowOnError>,
+  RequestOptions<TResponse, TResponseStyle, ThrowOnError>,
   'body' | 'path' | 'query' | 'url'
 > &
   Omit<TData, 'url'>;
@@ -215,18 +245,22 @@ export type OptionsLegacyParser<
 > = TData extends { body?: any }
   ? TData extends { headers?: any }
     ? OmitKeys<
-        RequestOptions<TResponseStyle, ThrowOnError>,
+        RequestOptions<unknown, TResponseStyle, ThrowOnError>,
         'body' | 'headers' | 'url'
       > &
         TData
-    : OmitKeys<RequestOptions<TResponseStyle, ThrowOnError>, 'body' | 'url'> &
+    : OmitKeys<
+        RequestOptions<unknown, TResponseStyle, ThrowOnError>,
+        'body' | 'url'
+      > &
         TData &
-        Pick<RequestOptions<TResponseStyle, ThrowOnError>, 'headers'>
+        Pick<RequestOptions<unknown, TResponseStyle, ThrowOnError>, 'headers'>
   : TData extends { headers?: any }
     ? OmitKeys<
-        RequestOptions<TResponseStyle, ThrowOnError>,
+        RequestOptions<unknown, TResponseStyle, ThrowOnError>,
         'headers' | 'url'
       > &
         TData &
-        Pick<RequestOptions<TResponseStyle, ThrowOnError>, 'body'>
-    : OmitKeys<RequestOptions<TResponseStyle, ThrowOnError>, 'url'> & TData;
+        Pick<RequestOptions<unknown, TResponseStyle, ThrowOnError>, 'body'>
+    : OmitKeys<RequestOptions<unknown, TResponseStyle, ThrowOnError>, 'url'> &
+        TData;