refactor file retrieval methods to fix zip handling

hsclient/hydroshare.py

@@ -1359,19 +1359,38 @@ def retrieve_string(self, path):
 
     def retrieve_file(self, path, save_path=""):
         file = self.get(path, status_code=200, allow_redirects=True)
-        filename = path.split("/")[-1]
-        downloaded_file = os.path.join(save_path, filename)
-        with open(downloaded_file, 'wb') as f:
-            f.write(file.content)
-        return downloaded_file
+        self.write_file(path, file.content, save_path)
 
     def retrieve_bag(self, path, save_path=""):
-        file = self.get(path, status_code=200, allow_redirects=True)
-
-        if file.headers['Content-Type'] != "application/zip":
+        print(f"Retrieving {path}")
+        response = self.get(path, status_code=200, allow_redirects=True)
+
+        file_is_ready = False
+        content_type = response.headers['Content-Type']
+
+        if content_type == "application/zip":
+            # if the path doesn't end with .zip, add it
+            if not path.endswith(".zip"):
+                path += ".zip"
+            file_is_ready = True
+        if content_type == "binary/octet-stream":
+            # here we assume that the stream is a zip file
+            if not path.endswith(".zip"):
+                path += ".zip"
+            file_is_ready = True
+
+        if not file_is_ready:
             time.sleep(CHECK_TASK_PING_INTERVAL)
             return self.retrieve_bag(path, save_path)
-        return self.retrieve_file(path, save_path)
+
+        self.write_file(path, response.content, save_path)
+
+    def write_file(self, path, content, save_path=""):
+        filename = path.split("/")[-1]
+        downloaded_file = os.path.join(save_path, filename)
+        with open(downloaded_file, 'wb') as f:
+            f.write(content)
+        return downloaded_file
 
     def check_task(self, task_id):
         response = self.get(f"/hsapi/taskstatus/{task_id}/", status_code=200)