From 00a5641cb9e6205ca13064ff7184720299fdab64 Mon Sep 17 00:00:00 2001
From: usmangani1 <sgosman_chem@yahoo.com>
Date: Wed, 2 Sep 2020 11:40:56 +0530
Subject: [PATCH] Fix:s3 Presign Put Request with File upload (#3235)

* Fix:s3 Presign Put Request with File upload

* Added imports in test

Co-authored-by: usmankb <usman@krazybee.com>
---
 moto/s3/responses.py     |  5 +++++
 tests/test_s3/test_s3.py | 25 ++++++++++++++++++++++++-
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/moto/s3/responses.py b/moto/s3/responses.py
index 603571c0d..364ae4623 100644
--- a/moto/s3/responses.py
+++ b/moto/s3/responses.py
@@ -1092,6 +1092,11 @@ class ResponseObject(_TemplateEnvironmentMixin, ActionAuthenticatorMixin):
         else:
             # Flask server
             body = request.data
+            # when the data is being passed as a file
+            if request.files and not body:
+                for _, value in request.files.items():
+                    body = value.stream.read()
+
         if body is None:
             body = b""
 
diff --git a/tests/test_s3/test_s3.py b/tests/test_s3/test_s3.py
index 6622b2f41..078abfa3b 100644
--- a/tests/test_s3/test_s3.py
+++ b/tests/test_s3/test_s3.py
@@ -3,7 +3,7 @@ from __future__ import unicode_literals
 
 import datetime
 import sys
-
+import os
 from boto3 import Session
 from six.moves.urllib.request import urlopen
 from six.moves.urllib.error import HTTPError
@@ -1054,6 +1054,29 @@ def test_streaming_upload_from_file_to_presigned_url():
     assert response.status_code == 200
 
 
+@mock_s3
+def test_multipart_upload_from_file_to_presigned_url():
+    s3 = boto3.client("s3", region_name=DEFAULT_REGION_NAME)
+    s3.create_bucket(Bucket="mybucket")
+
+    params = {"Bucket": "mybucket", "Key": "file_upload"}
+    presigned_url = boto3.client("s3").generate_presigned_url(
+        "put_object", params, ExpiresIn=900
+    )
+
+    file = open("text.txt", "w")
+    file.write("test")
+    file.close()
+    files = {"upload_file": open("text.txt", "rb")}
+
+    requests.put(presigned_url, files=files)
+    resp = s3.get_object(Bucket="mybucket", Key="file_upload")
+    data = resp["Body"].read()
+    assert data == b"test"
+    # cleanup
+    os.remove("text.txt")
+
+
 @mock_s3
 def test_s3_object_in_private_bucket():
     s3 = boto3.resource("s3")