Implemented writable streams interface

README.md

@@ -32,7 +32,7 @@ if (fd) {
 
 ```
 class SRT {
-  createSocket(): socket:Number
+  createSocket(sender?:Boolean): socket:Number
   bind(socket:Number, address:String, port:Number): result:Number
   listen(socket:Number, backlog:Number): result:Number
   connect(socket:Number, host:String, port:Number): result:Number
@@ -66,6 +66,21 @@ srt.connect(readStream => {
 });
 ```
 
+### Writable Stream
+
+Example of a writable stream
+
+```
+const fs = require('fs');
+const source = fs.createReadStream('./input');
+const { SRTWriteStream } = require('@eyevinn/srt');
+
+const srt = new SRTWriteStream('127.0.0.1', 1234);
+srt.connect(writeStream => {
+  source.pipe(writeStream);
+});
+```
+
 ## [Contributing](CONTRIBUTING.md)
 
 In addition to contributing code, you can help to triage issues. This can include reproducing bug reports, or asking for vital information such as version numbers or reproduction instructions. 

examples/writable.js

@@ -0,0 +1,8 @@
+const fs = require('fs');
+const source = fs.createReadStream(process.argv[2], { highWaterMark: 1316 });
+const { SRTWriteStream } = require('../index.js');
+
+const srt = new SRTWriteStream('127.0.0.1', 1234);
+srt.connect(writeStream => {
+  source.pipe(writeStream);
+});

index.js

@@ -1,9 +1,10 @@
 const LIB = require('./build/Release/node_srt.node');
 const Server = require('./src/server.js');
-const { SRTReadStream } = require('./src/stream.js');
+const { SRTReadStream, SRTWriteStream } = require('./src/stream.js');
 
 module.exports = {
   SRT: LIB.SRT,
   Server: Server,
-  SRTReadStream
+  SRTReadStream,
+  SRTWriteStream
 }

src/node-srt.cc

@@ -44,11 +44,20 @@ Napi::Value NodeSRT::CreateSocket(const Napi::CallbackInfo& info) {
   Napi::Env env = info.Env();
   Napi::HandleScope scope(env);
 
+  Napi::Boolean isSender = Napi::Boolean::New(env, false);
+  if (info.Length() > 0) {
+    isSender = info[0].As<Napi::Boolean>();
+  }
+  
   SRTSOCKET socket = srt_socket(AF_INET, SOCK_DGRAM, 0);
   if (socket == SRT_ERROR) {
     Napi::Error::New(env, srt_getlasterror_str()).ThrowAsJavaScriptException();
     return Napi::Number::New(env, SRT_ERROR);
   }
+  if (isSender) {
+    int yes = 1;
+    srt_setsockflag(socket, SRTO_SENDER, &yes, sizeof(yes));
+  }
   return Napi::Number::New(env, socket);
 }
 

src/node-srt.h

@@ -16,4 +16,4 @@ class NodeSRT : public Napi::ObjectWrap<NodeSRT> {
     Napi::Value Close(const Napi::CallbackInfo& info);
     Napi::Value Read(const Napi::CallbackInfo& info);
     Napi::Value Write(const Napi::CallbackInfo& info);
-};
+};

src/stream.js

@@ -1,4 +1,4 @@
-const { Readable } = require('stream');
+const { Readable, Writable } = require('stream');
 const LIB = require('../build/Release/node_srt.node');
 const debug = require('debug')('srt-stream');
 
@@ -56,6 +56,30 @@ class SRTReadStream extends Readable {
   }
 }
 
+class SRTWriteStream extends Writable {
+  constructor(address, port, opts) {
+    super();
+    this.srt = new LIB.SRT();
+    this.socket = this.srt.createSocket();
+    this.address = address;
+    this.port = port;
+  }
+
+  connect(cb) {
+    this.srt.connect(this.socket, this.address, this.port);
+    this.fd = this.socket;
+    if (this.fd) {
+      cb(this);
+    }
+  }
+
+  _write(chunk, encoding, callback) {
+    this.srt.write(this.fd, chunk);
+    callback();
+  }
+}
+
 module.exports = {
-  SRTReadStream
+  SRTReadStream,
+  SRTWriteStream
 }