add option to specify RTSP transport protocol

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## 1.5.0 (2021-07-14)
+
+- feat: add option to specify RTSP transport protocol (#85)
+
 ## 1.4.1 (2021-06-18)
 
 - fix: fix streams not being killed when there are multiple users and multiple streams (#74)

README.md

@@ -99,20 +99,14 @@ This is expected, and you can silence the warning by adding `process.setMaxListe
 
 ### Improving the video quality
 
-Depending on your network configuration, you can try add the following `additionalFlags` to improve the stream quality:
+Depending on your network configuration, you can try the following options to improve the stream quality:
 
-<!-- prettier-ignore -->
 ```js
-app.ws('/api/stream', proxy({
-  additionalFlags: [
+// try this:
+app.ws('/api/stream', proxy({ additionalFlags: ['-q', '1'] }));
 
-    // try this:
-    '-rtsp_transport', 'tcp',
-
-    // or this:
-    '-q', '1',
-  ],
-}));
+// or this:
+app.ws('/api/stream', proxy({ transport: 'tcp' }));
 ```
 
 Note that both these methods will use more bandwidth.

index.js

@@ -10,6 +10,7 @@ const { version } = require('./package.json');
  *  url: string;
  *  additionalFlags?: string[];
  *  verbose?: boolean;
+ *  transport?: 'udp' | 'tcp' | 'udp_multicast' | 'http';
  * }} Options
  *
  * @typedef {import("express").Application} Application
@@ -23,12 +24,23 @@ class InboundStreamWrapper {
   }
 
   /** @param {Options} props */
-  start({ url, additionalFlags = [] }) {
+  start({ url, additionalFlags = [], transport }) {
     if (this.verbose) console.log('[rtsp-relay] Creating brand new stream');
 
+    // validate config
+    const txpConfigInvalid = additionalFlags.indexOf('-rtsp_transport');
+    // eslint-disable-next-line no-bitwise
+    if (~txpConfigInvalid) {
+      const val = additionalFlags[0o1 + txpConfigInvalid];
+      console.warn(
+        `[rtsp-relay] (!) Do not specify -rtsp_transport=${val} in additionalFlags, use the option \`transport: '${val}'\``,
+      );
+    }
+
     this.stream = spawn(
       ffmpegPath,
       [
+        ...(transport ? ['-rtsp_transport', transport] : []), // this must come before `-i [url]`, see #82
         '-i',
         url,
         '-f', // force format

package.json

@@ -1,6 +1,6 @@
 {
   "name": "rtsp-relay",
-  "version": "1.4.1",
+  "version": "1.5.0",
   "author": "Kyle Hensel",
   "license": "MIT",
   "description": "📽 Relay an RTSP stream through an existing express.js server",