From 00ad03b709275e185ccb5b8e80cb7db4b9071d56 Mon Sep 17 00:00:00 2001
From: Dmitry Tantsur <dtantsur@protonmail.com>
Date: Tue, 30 Jun 2020 10:51:53 +0200
Subject: [PATCH] Fixes minor issues in the read() retries patch

Follow-up to commit c5b97eb781cf9851f9abe87a1500b4da55b8bde8.

Two things slipped through the cracks:
* ImageDownloadError was instantiated incorrectly, resulting in a wrong
  error message. This was uncovered by using assertRaisesRegext in tests.
* We allowed calling write(None). This was uncovered by avoiding sleep(4)
  in tests and enabling more failed calls before timeout.

Change-Id: If5e798c5461ea3e474a153574b0db2da96f2dfa8
---
 ironic_python_agent/extensions/standby.py                 | 3 ++-
 ironic_python_agent/tests/unit/extensions/test_standby.py | 7 ++++---
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/ironic_python_agent/extensions/standby.py b/ironic_python_agent/extensions/standby.py
index 0a120770f..e687d10ef 100644
--- a/ironic_python_agent/extensions/standby.py
+++ b/ironic_python_agent/extensions/standby.py
@@ -356,13 +356,14 @@ class ImageDownload(object):
             if chunk:
                 self._last_chunk_time = time.time()
                 self._hash_algo.update(chunk)
+                yield chunk
             elif (time.time() - self._last_chunk_time
                   > CONF.image_download_connection_timeout):
                 LOG.error('Timeout reached waiting for a chunk of data from '
                           'a remote server.')
                 raise errors.ImageDownloadError(
+                    self._image_info['id'],
                     'Timed out reading next chunk from webserver')
-            yield chunk
 
     def verify_image(self, image_location):
         """Verifies the checksum of the local images matches expectations.
diff --git a/ironic_python_agent/tests/unit/extensions/test_standby.py b/ironic_python_agent/tests/unit/extensions/test_standby.py
index 4fbb9e15d..5d27f6d73 100644
--- a/ironic_python_agent/tests/unit/extensions/test_standby.py
+++ b/ironic_python_agent/tests/unit/extensions/test_standby.py
@@ -1234,8 +1234,8 @@ class TestStandbyExtension(base.IronicAgentTest):
                 return self
 
             def __next__(self):
-                if self.count == 1:
-                    time.sleep(4)
+                if self.count:
+                    time.sleep(0.1)
                     return None
                 self.count += 1
                 return "meow"
@@ -1253,8 +1253,9 @@ class TestStandbyExtension(base.IronicAgentTest):
         hexdigest_mock = md5_mock.return_value.hexdigest
         hexdigest_mock.return_value = image_info['checksum']
         requests_mock.side_effect = create_timeout
-        self.assertRaises(
+        self.assertRaisesRegex(
             errors.ImageDownloadError,
+            'Timed out reading next chunk',
             self.agent_extension._stream_raw_image_onto_device,
             image_info,
             '/dev/foo')