Implement stream interfaces in Handle

composer.json

@@ -26,7 +26,8 @@
         }
     ],
     "require": {
-        "amphp/amp": "dev-master as 2.0"
+        "amphp/amp": "^2.0",
+        "amphp/byte-stream": "dev-master as 0.1"
     },
     "minimum-stability": "dev",
     "require-dev": {

lib/BlockingHandle.php

@@ -29,14 +29,14 @@ class BlockingHandle implements Handle {
     /**
      * {@inheritdoc}
      */
-    public function read(int $length): Promise {
+    public function read(int $length = self::DEFAULT_READ_LENGTH): Promise {
         if ($this->fh === null) {
             throw new \Error("The file has been closed");
         }
 
         $data = \fread($this->fh, $length);
         if ($data !== false) {
-            return new Success($data);
+            return new Success(\strlen($data) ? $data : null);
         } else {
             return new Failure(new FilesystemException(
                 "Failed reading from file handle"
@@ -62,6 +62,15 @@ class BlockingHandle implements Handle {
         }
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function end(string $data = ""): Promise {
+        $promise = $this->write($data);
+        $promise->onResolve([$this, "close"]);
+        return $promise;
+    }
+
     /**
      * {@inheritdoc}
      */

lib/EioHandle.php

@@ -30,7 +30,7 @@ class EioHandle implements Handle {
     /**
      * {@inheritdoc}
      */
-    public function read(int $length): Promise {
+    public function read(int $length = self::DEFAULT_READ_LENGTH): Promise {
         $deferred = new Deferred;
         $op = new \StdClass;
         $op->type = self::OP_READ;
@@ -74,8 +74,9 @@ class EioHandle implements Handle {
                 \eio_get_last_error($req)
             ));
         } else {
-            $this->position = $op->position + \strlen($result);
-            $op->deferred->resolve($result);
+            $length = \strlen($result);
+            $this->position = $op->position + $length;
+            $op->deferred->resolve($length ? $result : null);
         }
         if ($this->queue) {
             $this->dequeue();
@@ -104,6 +105,15 @@ class EioHandle implements Handle {
         return $deferred->promise();
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function end(string $data = ""): Promise {
+        $promise = $this->write($data);
+        $promise->onResolve([$this, "close"]);
+        return $promise;
+    }
+
     private function onWrite($op, $result, $req) {
         $this->isActive = false;
         ($this->incrementor)(-1);

lib/Handle.php

@@ -2,16 +2,20 @@
 
 namespace Amp\File;
 
+use Amp\ByteStream\InputStream;
+use Amp\ByteStream\OutputStream;
 use Amp\Promise;
 
-interface Handle {
+interface Handle extends InputStream, OutputStream {
+    const DEFAULT_READ_LENGTH = 8192;
+
     /**
      * Read $len bytes from the open file handle starting at $offset
      *
      * @param int $length
-     * @return \Amp\Promise<string>
+     * @return \Amp\Promise<string|null>
      */
-    public function read(int $length): Promise;
+    public function read(int $length = 8192): Promise;
 
     /**
      * Write $data to the open file handle starting at $offset
@@ -21,6 +25,15 @@ interface Handle {
      */
     public function write(string $data): Promise;
 
+    /**
+     * Write $data to the open file handle and close the handle once the write completes.
+     *
+     * @param string $data
+     *
+     * @return \Amp\Promise<int>
+     */
+    public function end(string $data = ""): Promise;
+
     /**
      * Close the file handle
      *

lib/ParallelHandle.php

@@ -80,7 +80,7 @@ class ParallelHandle implements Handle {
         return ($this->pendingWrites > 0) ? false : ($this->size <= $this->position);
     }
 
-    public function read(int $length): Promise {
+    public function read(int $length = self::DEFAULT_READ_LENGTH): Promise {
         if ($this->id === null) {
             throw new \Error("The file has been closed");
         }
@@ -113,6 +113,15 @@ class ParallelHandle implements Handle {
         return new Coroutine($this->doWrite($data));
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function end(string $data = ""): Promise {
+        $promise = $this->write($data);
+        $promise->onResolve([$this, "close"]);
+        return $promise;
+    }
+
     private function doWrite(string $data): \Generator {
         ++$this->pendingWrites;
 

lib/UvHandle.php

@@ -40,7 +40,7 @@ class UvHandle implements Handle {
     /**
      * {@inheritdoc}
      */
-    public function read(int $readLen): Promise {
+    public function read(int $readLen = self::DEFAULT_READ_LENGTH): Promise {
         $deferred = new Deferred;
         $op = new \StdClass;
         $op->type = self::OP_READ;
@@ -78,6 +78,15 @@ class UvHandle implements Handle {
         return $deferred->promise();
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function end(string $data = ""): Promise {
+        $promise = $this->write($data);
+        $promise->onResolve([$this, "close"]);
+        return $promise;
+    }
+
     private function doRead($op) {
         $this->driver->reference($this->busy);
         $onRead = function ($fh, $result, $buffer) use ($op) {
@@ -88,8 +97,9 @@ class UvHandle implements Handle {
                     \uv_strerror($result)
                 ));
             } else {
-                $this->position = $op->position + strlen($buffer);
-                $op->promisor->resolve($buffer);
+                $length = strlen($buffer);
+                $this->position = $op->position + $length;
+                $op->promisor->resolve($length ? $buffer : null);
             }
             if ($this->queue) {
                 $this->dequeue();