PESDLC-1319 Use exceptions and add timeout

tests/rptest/clients/kubectl.py

@@ -139,9 +139,17 @@ def _install(self):
     def logger(self) -> Logger:
         return self._redpanda.logger
 
-    def _local_cmd(self, cmd: list[str]):
+    def _local_cmd(self, cmd: list[str], timeout=900):
         """Run the given command locally and return the stdout as bytes.
-           Logs stdout and stderr on failure."""
+           Logs stdout and stderr on failure.
+           
+           cmd: list[str]: command to run
+           
+           throws CalledProcessError on non-zero exit code
+           thwows 
+           
+           returns: stdout as string if not empty, else stderr
+        """
         def _prepare_output(sout: str, serr: str) -> str:
             return f"\n--------- stdout -----------\n{sout}" \
                    f"\n--------- stderr -----------\n{serr}\n"
@@ -155,20 +163,34 @@ def _prepare_output(sout: str, serr: str) -> str:
                                    stdout=subprocess.PIPE,
                                    stderr=subprocess.PIPE,
                                    text=True)
-        s_out, s_err = process.communicate()
+        try:
+            s_out, s_err = process.communicate()
+            # safety check for process termination
+            if process.poll() is None:
+                # Should never happen (c)
+                process.kill()
+        except subprocess.TimeoutExpired:
+            process.kill()
+            s_out, s_err = process.communicate()
+            raise subprocess.TimeoutExpired(cmd, timeout, s_out, s_err)
+
+        # Log all collected strings, including JSONs collected
         self.logger.debug(_prepare_output(s_out, s_err))
 
         # TODO: Handle s_err output
         # It will be hard to detect errors as a lot of apps and utils
-        # just uses stderr as normal output. For example, tsh
-
-        process.kill()
+        # just uses stderr as normal output. For example, tsh (teleport tunnel)
 
         if process.returncode != 0:
-            self.logger.info(f'Command failed (rc={process.returncode}).\n'
-                             f'{_prepare_output(s_out, s_err)}')
-            raise RuntimeError("Last command returned non-zero exit code")
-
+            self.logger.info(f"Command failed (rc={process.returncode}): "
+                             f"'{' '.join(cmd)}'\n"
+                             f"{_prepare_output(s_out, s_err)}")
+            raise subprocess.CalledProcessError(process.returncode, cmd, s_out,
+                                                s_err)
+
+        # Most of the time stdout will hold valuable data
+        # In rare occasions when return code is 0, and and stderr is not empty
+        # return that instead.
         return s_out if len(s_out) > 0 else s_err
 
     def _ssh_cmd(self, cmd: list[str]):