feat: handle error when log file is empty (#4859)

Fixes GH-4686

cloudinit/analyze/show.py

@@ -7,6 +7,7 @@
 import datetime
 import json
 import os
+import sys
 import time
 
 from cloudinit import subp, util
@@ -370,6 +371,9 @@ def load_events_infile(infile):
     :return: json version of logfile, raw file
     """
     data = infile.read()
+    if not data.strip():
+        sys.stderr.write("Empty file %s\n" % infile.name)
+        sys.exit(1)
     try:
         return json.loads(data), data
     except ValueError:

tests/unittests/analyze/test_show.py

@@ -0,0 +1,24 @@
+from collections import namedtuple
+
+import pytest
+
+from cloudinit.analyze import analyze_show
+
+
+@pytest.fixture
+def mock_io(tmp_path):
+    """Mock args for configure_io function"""
+    infile = tmp_path / "infile"
+    outfile = tmp_path / "outfile"
+    return namedtuple("MockIO", ["infile", "outfile"])(infile, outfile)
+
+
+class TestAnalyzeShow:
+    """Test analyze_show (and/or helpers) in cloudinit/analyze/__init__.py"""
+
+    def test_empty_logfile(self, mock_io, capsys):
+        """Test analyze_show with an empty logfile"""
+        mock_io.infile.write_text("")
+        with pytest.raises(SystemExit):
+            analyze_show("dontcare", mock_io)
+        assert capsys.readouterr().err == f"Empty file {mock_io.infile}\n"

tools/.github-cla-signers

@@ -7,6 +7,7 @@ ajmyyra
 akutz
 AlexBaranowski
 AlexSv04047
+AliyevH
 Aman306
 andgein
 andrew-lee-metaswitch