From c33009ae3a307c943c32405f93bdadd6c4f8ed6b Mon Sep 17 00:00:00 2001
From: Howard Lopez <lopehowa@amazon.com>
Date: Fri, 1 Mar 2019 12:04:50 -0800
Subject: [PATCH 1/4] Modify S3 Stream Wrapper to work with PHP 7+ for empty
 file uploads

---
 src/S3/StreamWrapper.php | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/S3/StreamWrapper.php b/src/S3/StreamWrapper.php
index 33954a186d..bba66c0992 100644
--- a/src/S3/StreamWrapper.php
+++ b/src/S3/StreamWrapper.php
@@ -94,6 +94,8 @@ class StreamWrapper
     /** @var string The opened protocol (e.g., "s3") */
     private $protocol = 's3';
 
+    private $isFlushed = false;
+
     /**
      * Register the 's3://' stream wrapper
      *
@@ -127,12 +129,16 @@ public static function register(
 
     public function stream_close()
     {
+        if ($this->body->getSize() === 0 && !($this->isFlushed)) {
+            $this->stream_flush();
+        }
         $this->body = $this->cache = null;
     }
 
     public function stream_open($path, $mode, $options, &$opened_path)
     {
         $this->initProtocol($path);
+        $this->isFlushed = false;
         $this->params = $this->getBucketKey($path);
         $this->mode = rtrim($mode, 'bt');
 
@@ -156,6 +162,7 @@ public function stream_eof()
 
     public function stream_flush()
     {
+        $this->isFlushed = true;
         if ($this->mode == 'r') {
             return false;
         }

From 6267c240e7d2bcd9ef729462713000bce3de4a99 Mon Sep 17 00:00:00 2001
From: Howard Lopez <lopehowa@amazon.com>
Date: Wed, 6 Mar 2019 14:08:06 -0800
Subject: [PATCH 2/4] Add test for empty file write using stream wrapper

---
 tests/S3/StreamWrapperTest.php | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/tests/S3/StreamWrapperTest.php b/tests/S3/StreamWrapperTest.php
index bd0ab9cac4..23f53eaf4b 100644
--- a/tests/S3/StreamWrapperTest.php
+++ b/tests/S3/StreamWrapperTest.php
@@ -170,6 +170,25 @@ public function testCanOpenWriteOnlyStreams()
         $this->assertEquals('test', (string) $cmd['Body']);
     }
 
+    public function testCanWriteEmptyFileToStream()
+    {
+        $history = new History();
+        $this->client->getHandlerList()->appendSign(Middleware::history($history));
+        $this->addMockResults($this->client, [new Result()]);
+        $s = fopen('s3://bucket/key', 'w');
+        $this->assertEquals(0, fwrite($s, ''));
+        $this->assertTrue(fclose($s));
+
+        // Ensure that the stream was flushed even with zero characters, and
+        // that it only executed PutObject once.
+        $this->assertCount(1, $history);
+        $cmd = $history->getLastCommand();
+        $this->assertEquals('PutObject', $cmd->getName());
+        $this->assertEquals('bucket', $cmd['Bucket']);
+        $this->assertEquals('key', $cmd['Key']);
+        $this->assertEquals('', (string) $cmd['Body']);
+    }
+
     /**
      * @expectedException \PHPUnit\Framework\Error\Warning
      * @expectedExceptionMessage 403 Forbidden

From a71e1128f8d871903b0f6199e992810013a1de30 Mon Sep 17 00:00:00 2001
From: Howard Lopez <lopehowa@amazon.com>
Date: Wed, 6 Mar 2019 14:27:56 -0800
Subject: [PATCH 3/4] Add changelog

---
 .changes/nextrelease/stream_wrapper_fixes.json | 7 +++++++
 1 file changed, 7 insertions(+)
 create mode 100644 .changes/nextrelease/stream_wrapper_fixes.json

diff --git a/.changes/nextrelease/stream_wrapper_fixes.json b/.changes/nextrelease/stream_wrapper_fixes.json
new file mode 100644
index 0000000000..8d79d0099f
--- /dev/null
+++ b/.changes/nextrelease/stream_wrapper_fixes.json
@@ -0,0 +1,7 @@
+[
+    {
+        "type": "feature",
+        "category": "S3",
+        "description": "Updates the S3 stream wrapper to be able to write empty files for PHP 7+."
+    }
+]
\ No newline at end of file

From 56e1be2e276f81aa297878b325a71fd016ba4658 Mon Sep 17 00:00:00 2001
From: Howard Lopez <lopehowa@amazon.com>
Date: Wed, 6 Mar 2019 14:35:42 -0800
Subject: [PATCH 4/4] Add doc

---
 src/S3/StreamWrapper.php | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/S3/StreamWrapper.php b/src/S3/StreamWrapper.php
index bba66c0992..fbf6183b67 100644
--- a/src/S3/StreamWrapper.php
+++ b/src/S3/StreamWrapper.php
@@ -94,6 +94,7 @@ class StreamWrapper
     /** @var string The opened protocol (e.g., "s3") */
     private $protocol = 's3';
 
+    /** @var bool Keeps track of whether stream has been flushed since opening */
     private $isFlushed = false;
 
     /**