Optimize Rewindable usage (#352)

* Optimize Rewindable usage

* Remove GeneratorStream and rename travers

* Small fixes

Author: jderusse

src/Signer/SignerV4.php

@@ -8,7 +8,9 @@
 use AsyncAws\Core\RequestContext;
 use AsyncAws\Core\Stream\FixedSizeStream;
 use AsyncAws\Core\Stream\IterableStream;
+use AsyncAws\Core\Stream\ReadOnceResultStream;
 use AsyncAws\Core\Stream\RequestStream;
+use AsyncAws\Core\Stream\RewindableStream;
 use AsyncAws\Core\Stream\StringStream;
 
 /**
@@ -77,6 +79,11 @@ protected function buildBodyDigest(Request $request, bool $isPresign): string
         if ($request->hasHeader('x-amz-content-sha256')) {
             $hash = ((array) $request->getHeader('x-amz-content-sha256'))[0];
         } else {
+            $body = $request->getBody();
+            if ($body instanceof ReadOnceResultStream) {
+                $request->setBody($body = RewindableStream::create($body));
+            }
+
             $hash = $request->getBody()->hash();
         }
 
@@ -245,6 +252,13 @@ private function convertBodyToStream(Request $request, \DateTimeInterface $now,
             $contentLength = $body->length();
         }
 
+        // If content length is unknown, use the rewindable stream to read it once locally in order to get the length
+        if (null === $contentLength) {
+            $request->setBody($body = RewindableStream::create($body));
+            $body->read();
+            $contentLength = $body->length();
+        }
+
         // no need to stream small body. It's simple to convert it to string directly
         if ($contentLength < self::CHUNK_SIZE) {
             $request->setBody($body = StringStream::create($body));

src/Stream/CallableStream.php

@@ -8,11 +8,11 @@
  * Convert a "Curl Callable" into a Stream
  * The Callable must return a chunk at each call. And return an empty string on last call.
  *
- * @internal
- *
  * @author Jérémy Derussé <[email protected]>
+ *
+ * @internal
  */
-final class CallableStream implements RequestStream
+final class CallableStream implements ReadOnceResultStream, RequestStream
 {
     private $content;
 

src/Stream/FixedSizeStream.php

@@ -7,9 +7,9 @@
 /**
  * A Stream decorator that return Chunk with the same exact size.
  *
- * @internal
- *
  * @author Jérémy Derussé <[email protected]>
+ *
+ * @internal
  */
 final class FixedSizeStream implements RequestStream
 {

src/Stream/IterableStream.php

@@ -7,11 +7,11 @@
 /**
  * Convert an iterator into a Stream.
  *
- * @internal
- *
  * @author Jérémy Derussé <[email protected]>
+ *
+ * @internal
  */
-final class IterableStream implements RequestStream
+final class IterableStream implements ReadOnceResultStream, RequestStream
 {
     private $content;
 

src/Stream/ReadOnceResultStream.php

@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+namespace AsyncAws\Core\Stream;
+
+/**
+ * Marker for ResultStream that can be read only once.
+ */
+interface ReadOnceResultStream
+{
+}

src/Stream/RequestStream.php

@@ -5,9 +5,9 @@
 /**
  * Provides method to convert a input into string or chunks.
  *
- * @internal
- *
  * @author Jérémy Derussé <[email protected]>
+ *
+ * @internal
  */
 interface RequestStream extends \IteratorAggregate
 {

src/Stream/ResourceStream.php

@@ -7,9 +7,9 @@
 /**
  * Convert a resource into a Stream.
  *
- * @internal
- *
  * @author Jérémy Derussé <[email protected]>
+ *
+ * @internal
  */
 final class ResourceStream implements RequestStream
 {

src/Stream/RewindableStream.php

@@ -13,9 +13,9 @@
  * - length
  * - hash
  *
- * @internal
- *
  * @author Jérémy Derussé <[email protected]>
+ *
+ * @internal
  */
 final class RewindableStream implements RequestStream
 {
@@ -107,4 +107,11 @@ public function hash(string $algo = 'sha256', bool $raw = false): string
 
         return hash_final($ctx, $raw);
     }
+
+    public function read(): void
+    {
+        // Use getIterator() to read stream content to $this->fallback
+        foreach ($this as $chunk) {
+        }
+    }
 }

src/Stream/StreamFactory.php

@@ -17,7 +17,7 @@ public static function create($content): RequestStream
             return StringStream::create($content ?? '');
         }
         if (\is_callable($content)) {
-            return RewindableStream::create(CallableStream::create($content));
+            return CallableStream::create($content);
         }
         if (\is_iterable($content)) {
             return IterableStream::create($content);

src/Stream/StringStream.php

@@ -7,9 +7,9 @@
 /**
  * Convert a string into a Stream.
  *
- * @internal
- *
  * @author Jérémy Derussé <[email protected]>
+ *
+ * @internal
  */
 final class StringStream implements RequestStream
 {