Merge "Limit bytes when reading Ansible output"

tests/unit/test_v3.py

@@ -8067,6 +8067,23 @@ class TestJobOutput(AnsibleZuulTestCase):
         self.assertReportedStat(post_failure_stat, value='1', kind='c')
         self.assertReportedStat(post_failure_stat, kind='ms')
 
+    @mock.patch("zuul.executor.server.OUTPUT_MAX_LINE_BYTES", 50)
+    def test_job_output_max_line_bytes(self):
+        logger = logging.getLogger('zuul.AnsibleJob')
+        output = io.StringIO()
+        logger.addHandler(logging.StreamHandler(output))
+
+        A = self.fake_gerrit.addFakeChange('org/project', 'master', 'A')
+        self.fake_gerrit.addEvent(A.getPatchsetCreatedEvent(1))
+        self.waitUntilSettled()
+
+        self.assertHistory([
+            dict(name='job-output', result='SUCCESS', changes='1,1'),
+        ], ordered=False)
+
+        log_output = output.getvalue()
+        self.assertIn('Ansible output exceeds max. line size of', log_output)
+
 
 class TestNoLog(AnsibleZuulTestCase):
     tenant_config_file = 'config/ansible-no-log/main.yaml'

zuul/executor/server.py

@@ -33,6 +33,7 @@ import threading
 import time
 import traceback
 from concurrent.futures.process import ProcessPoolExecutor, BrokenProcessPool
+from functools import partial
 
 from kazoo.exceptions import NoNodeError
 from kazoo.retry import KazooRetry
@@ -90,6 +91,7 @@ from zuul.zk.semaphore import SemaphoreHandler
 
 
 BUFFER_LINES_FOR_SYNTAX = 200
+OUTPUT_MAX_LINE_BYTES = 51200  # 50 MiB
 DEFAULT_FINGER_PORT = 7900
 DEFAULT_STREAM_PORT = 19885
 BLACKLISTED_ANSIBLE_CONNECTION_TYPES = [
@@ -2951,7 +2953,13 @@ class AnsibleJob(object):
             # don't count towards BUFFER_LINES_FOR_SYNTAX
             idx = 0
             first = True
-            for line in iter(self.proc.stdout.readline, b''):
+            for line in iter(
+                    partial(self.proc.stdout.readline, OUTPUT_MAX_LINE_BYTES),
+                    b''):
+                if line and line[-1:] != b'\n':
+                    self.log.warning(
+                        "Ansible output exceeds max. line size of %s MiB",
+                        OUTPUT_MAX_LINE_BYTES / 1024)
                 if first:
                     # When we receive our first log line, bwrap should
                     # have started Ansible and it should still be