feat: add disable retryDelay

README.md

@@ -1,4 +1,5 @@
 # Fastify SSE Plugin
+
 ![CI check](https://github.com/NodeFactoryIo/fastify-sse-v2/workflows/CI%20check/badge.svg?branch=master)
 [![npm version](https://badge.fury.io/js/fastify-sse-v2.svg)](https://badge.fury.io/js/fastify-sse-v2)
 
@@ -11,9 +12,11 @@ For `[email protected]` use [[email protected]](https://github.com/NodeFactoryIo/fast
 ```terminal
 yarn add fastify-sse-v2
 ```
+
 Register fastify-sse-v2 plugin into your fastify instance:
+
 ```javascript
-import {FastifySSEPlugin} from "fastify-sse-v2";
+import { FastifySSEPlugin } from "fastify-sse-v2";
 
 const server = fastify();
 server.register(FastifySSEPlugin);
@@ -22,74 +25,95 @@ server.register(FastifySSEPlugin);
 #### Sending events from AsyncIterable source
 
 ```javascript
-import {FastifySSEPlugin} from "fastify-sse-v2";
+import { FastifySSEPlugin } from "fastify-sse-v2";
 
 const server = fastify();
 server.register(FastifySSEPlugin);
 
 server.get("/", function (req, res) {
-    res.sse((async function * source () {
-          for (let i = 0; i < 10; i++) {
-            sleep(2000);
-            yield {id: String(i), data: "Some message"};
-          }
-    })());
+  res.sse(
+    (async function* source() {
+      for (let i = 0; i < 10; i++) {
+        sleep(2000);
+        yield { id: String(i), data: "Some message" };
+      }
+    })()
+  );
 });
 ```
+
 #### Sending individual events
 
 ```javascript
-import {FastifySSEPlugin} from "fastify-sse-v2";
+import { FastifySSEPlugin } from "fastify-sse-v2";
 
 const server = fastify();
 server.register(FastifySSEPlugin);
 
 server.get("/", async function (req, res) {
-    for (let i = 0; i < 10; i++) {
-      await sleep(2000);
-      res.sse({id: String(i), data: "Some message"});
-    }
+  for (let i = 0; i < 10; i++) {
+    await sleep(2000);
+    res.sse({ id: String(i), data: "Some message" });
+  }
 });
 
-fastify.get('/listenForChanges', {}, (request, reply) => {
-    const listenStream = fastify.db.watch('doc-uuid')
-        .on('data', (data)=>reply.sse({ data: JSON.stringify(data) }))
-        .on('delete', () => reply.sse({ event: 'close' }))
-    request.socket.on('close', ()=>listenStream.end())
-})
+fastify.get("/listenForChanges", {}, (request, reply) => {
+  const listenStream = fastify.db
+    .watch("doc-uuid")
+    .on("data", (data) => reply.sse({ data: JSON.stringify(data) }))
+    .on("delete", () => reply.sse({ event: "close" }));
+  request.socket.on("close", () => listenStream.end());
+});
 ```
 
 ##### Note
+
 - When sending individual events, the connection is kept open until you call `reply.sseContext.source.end()` to terminate the stream.
 
 ##### Sending events from EventEmmiters
 
-* [not supported in all nodejs versions](https://nodejs.org/api/events.html#events_events_on_emitter_eventname_options)
+- [not supported in all nodejs versions](https://nodejs.org/api/events.html#events_events_on_emitter_eventname_options)
 
 ```javascript
-import {FastifySSEPlugin} from "fastify-sse-v2";
-import {on} from "events";
+import { FastifySSEPlugin } from "fastify-sse-v2";
+import { on } from "events";
 
 const server = fastify();
 server.register(FastifySSEPlugin);
 
 server.get("/", function (req, res) {
-    res.sse(
-  (async function* () {
-    for await (const [event] of on(eventEmmitter, "update")) {
-      yield {
-        event: event.name,
-        data: JSON.stringify(event),
-      };
-    }
-  })()
-);
+  res.sse(
+    (async function* () {
+      for await (const [event] of on(eventEmmitter, "update")) {
+        yield {
+          event: event.name,
+          data: JSON.stringify(event),
+        };
+      }
+    })()
+  );
 });
 ```
 
+##### Parameter
+
+- You can set parameter `retryDelay` to `false` to disable the default behavior of sending retry, or set parameter `retryDelay` to `milliseconds` override the default 3000 retry interval .
+
+```javascript
+import { FastifySSEPlugin } from "fastify-sse-v2";
+
+const server = fastify();
+
+server.register(FastifySSEPlugin) // retryDelay default 3000
+
+server.register(FastifySSEPlugin, {
+  retryDelay: false // disable retryDelay
+  retryDelay: 5000 // override 5000
+})
+```
 
 ##### Note
+
 - to remove event listeners (or some other cleanup) when client closes connection,
- you can listen on connection closing event: `request.socket.on('close', () => abortController.abort());
+  you can listen on connection closing event: `request.socket.on('close', () => abortController.abort());
 `
-

src/plugin.ts

@@ -26,9 +26,11 @@ export const plugin: FastifyPluginAsync<SsePluginOptions> = async function (
         this.raw.setHeader("Connection", "keep-alive");
         this.raw.setHeader("Cache-Control", "no-cache,no-transform");
         this.raw.setHeader("x-no-compression", 1);
-        this.raw.write(
-          serializeSSEEvent({ retry: options.retryDelay || 3000 })
-        );
+        if (options.retryDelay !== false) {
+          this.raw.write(
+            serializeSSEEvent({ retry: options.retryDelay || 3000 })
+          );
+        }
         handleAsyncIterable(this, this.sseContext.source);
       }
       if (isAsyncIterable(source)) {

src/types.ts

@@ -2,5 +2,5 @@ export interface SsePluginOptions {
   /**
    * Update client reconnect interval (how long will client wait before trying to reconnect).
    */
-  retryDelay?: number;
+  retryDelay?: false | number;
 }