Add buffer packer

src/export/packer/buffer-stream.ts

@@ -0,0 +1,28 @@
+import { Writable } from "stream";
+
+export class BufferStream extends Writable {
+    private data: Buffer[];
+
+    constructor() {
+        super();
+
+        this.data = [];
+    }
+
+    // tslint:disable-next-line:no-any
+    public _write(chunk: any, encoding: string, next: (err?: Error) => void): void {
+        this.data.push(Buffer.from(chunk));
+        next();
+    }
+
+    // tslint:disable-next-line:ban-types
+    public end(cb?: Function): void {
+        super.end(cb);
+
+        this.emit("close");
+    }
+
+    public get Buffer(): Buffer {
+        return Buffer.concat(this.data);
+    }
+}