vdk-core: relevant info in step result

Why?

Sometimes the exact errors in user code are hard
to find in the stack trace

What?

Print relevant information from stack trace in
step results

How was this tested?

Ran locally
Functional test

What kind of change is this?

Feature/non-breaking

Signed-off-by: Dilyan Marinov <[email protected]>

projects/vdk-core/src/vdk/internal/builtin_plugins/run/cli_run.py

@@ -7,6 +7,7 @@
 import pathlib
 import re
 import sys
+import traceback
 from typing import cast
 from typing import Dict
 from typing import List
@@ -143,14 +144,41 @@ def __log_exec_result(self, execution_result: ExecutionResult) -> None:
 
     @staticmethod
     def __log_short_exec_result(execution_result):
+        def extract_relevant_lines(step):
+            out = []
+            if step.exception:
+                call_list = traceback.format_tb(step.exception.__traceback__)
+
+                for i, line in enumerate(call_list):
+                    # Check if the step name is in the line
+                    if step.name in line:
+                        out.append(line)
+                        j = i + 1
+                        # Pull in subsequent relevant lines
+                        # that do not come from another file
+                        while j < len(call_list) and not re.match(
+                            r'^\s*File "', call_list[j]
+                        ):
+                            out.append(call_list[j])
+                            j += 1
+                        # add the exception type and message
+                        out.append(
+                            f"{type(step.exception).__name__}: {str(step.exception)}"
+                        )
+            return out
+
         log.info(
             "Job execution result: "
             + execution_result.status.upper()
             + "\n"
-            + "Steps list:\n"
+            + "Step results:\n"
             + "".join(
                 [
-                    step.name + " - " + step.status.upper() + "\n"
+                    step.name
+                    + " - "
+                    + step.status.upper()
+                    + "\n"
+                    + "".join(extract_relevant_lines(step))
                     for step in execution_result.steps_list
                 ]
             )

projects/vdk-core/tests/functional/run/test_run_errors.py

@@ -229,3 +229,18 @@ def test_error_from_pandas_user_error(tmp_termination_msg_file):
         assert _get_job_status(tmp_termination_msg_file) == "User error"
         assert '"blamee": "User Error"' in result.output
         assert '"exception_name": "KeyError"' in result.output
+
+
+def test_run_simple_job_summary(tmp_termination_msg_file):
+    runner = CliEntryBasedTestRunner()
+
+    result: Result = runner.invoke(["run", util.job_path("fail-job")])
+    cli_assert_equal(1, result)
+    expected = f"""
+Step results:
+1_step.py - ERROR
+  File "{os.getcwd()}/jobs/fail-job/1_step.py", line 7, in run
+    raise ArithmeticError("cannot do math :(")
+ArithmeticError: cannot do math :(
+"""
+    assert expected in result.output