KVM unit tests: log collection for timeout failures

When KVM unit tests gets killed due to timeout, result.stdout
is empty and the test fails with "no results in stdout". In this
case it is useful to collect the logs from the "logs" directory
to debug the problem since we don't have any useful information
in stdout.

Signed-off-by: Anirudh Rayabharam <anrayabh@microsoft.com>

lisa/tools/chmod.py

@@ -9,5 +9,8 @@ class Chmod(Tool):
     def command(self) -> str:
         return "chmod"
 
+    def chmod(self, path: str, permission: str, sudo: bool = False) -> None:
+        self.run(f"{permission} {path}", sudo=sudo, force_run=True)
+
     def update_folder(self, path: str, permission: str, sudo: bool = False) -> None:
         self.run(f"-R {permission} {path}", sudo=sudo, force_run=True)

lisa/tools/ls.py

@@ -24,6 +24,21 @@ class Ls(Tool):
         )
         return 0 == cmd_result.exit_code
 
+    def list(self, path: str, sudo: bool = False) -> List[str]:
+        cmd_result = self.run(
+            f"-d {path}/*",
+            force_run=True,
+            sudo=sudo,
+            shell=True,
+        )
+
+        # can fail due to insufficient permissions, non existent
+        # files/dirs etc.
+        if cmd_result.exit_code == 0:
+            return cmd_result.stdout.split()
+        else:
+            return []
+
     def list_dir(self, path: str, sudo: bool = False) -> List[str]:
         cmd_result = self.node.execute(
             f"{self.command} -d {path}/*/",

microsoft/testsuites/kvm/kvm_unit_tests_tool.py

@@ -12,7 +12,7 @@ from lisa.executable import Tool
 from lisa.messages import SubTestMessage, TestStatus, create_test_result_message
 from lisa.operating_system import Posix
 from lisa.testsuite import TestResult
-from lisa.tools import Git, Make
+from lisa.tools import Chmod, Git, Ls, Make
 from lisa.util import LisaException
 
 
@@ -75,6 +75,7 @@ class KvmUnitTests(Tool):
 
         results = self._parse_results(exec_result.stdout)
         if not results:
+            self._save_all_logs(failure_logs_path)
             raise LisaException("Did not find any test results in stdout.")
 
         failed_tests = []
@@ -140,6 +141,18 @@ class KvmUnitTests(Tool):
                 log_path / f"{test_name}.failure.log",
             )
 
+    def _save_all_logs(self, log_path: Path) -> None:
+        logs_dir = self.repo_root / "logs"
+        self.node.tools[Chmod].chmod("a+x", str(logs_dir), sudo=True)
+        self.node.tools[Chmod].update_folder("a+r", str(logs_dir), sudo=True)
+        files = self.node.tools[Ls].list(str(logs_dir), sudo=True)
+        for f in files:
+            f_path = PurePath(f)
+            self.node.shell.copy_back(
+                f_path,
+                log_path / f"{f_path.name}",
+            )
+
     def _initialize(self, *args: Any, **kwargs: Any) -> None:
         tool_path = self.get_tool_path(use_global=True)
         self.repo_root = tool_path.joinpath("kvm-unit-tests")