Ending notebook execution early with sys.exit without raising an exce…

…ption (#449)

Support using sys.exit to end execution early without raising a papermill exception

papermill/execute.py

@@ -168,6 +168,8 @@ def raise_for_execution_errors(nb, output_path):
 
         for output in cell.outputs:
             if output.output_type == "error":
+                if output.ename == "SystemExit" and (output.evalue == "" or output.evalue == "0"):
+                    continue
                 error = PapermillExecutionError(
                     exec_count=cell.execution_count,
                     source=cell.source,

papermill/tests/notebooks/sysexit.ipynb

@@ -0,0 +1,52 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import sys"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "sys.exit()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "print(\"Cell should not execute.\")"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "dev",
+   "language": "python",
+   "name": "dev"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.7.1"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}

papermill/tests/notebooks/sysexit0.ipynb

@@ -0,0 +1,52 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import sys"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "sys.exit(0)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "print(\"Cell should not execute.\")"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "dev",
+   "language": "python",
+   "name": "dev"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.7.1"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}

papermill/tests/notebooks/sysexit1.ipynb

@@ -0,0 +1,52 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import sys"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "sys.exit(1)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "print(\"Cell should not execute.\")"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "dev",
+   "language": "python",
+   "name": "dev"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.7.1"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}

papermill/tests/test_execute.py

@@ -260,3 +260,50 @@ def test_execution_respects_cwd_assignment(self):
         self.assertTrue(
             os.path.isfile(os.path.join(self.base_test_dir, self.nb_test_executed_fname))
         )
+
+
+class TestSysExit(unittest.TestCase):
+    def setUp(self):
+        self.test_dir = tempfile.mkdtemp()
+
+    def tearDown(self):
+        shutil.rmtree(self.test_dir)
+
+    def test_sys_exit(self):
+        notebook_name = 'sysexit.ipynb'
+        result_path = os.path.join(self.test_dir, 'output_{}'.format(notebook_name))
+        execute_notebook(get_notebook_path(notebook_name), result_path)
+        nb = load_notebook_node(result_path)
+        self.assertEqual(nb.cells[0].cell_type, "code")
+        self.assertEqual(nb.cells[0].execution_count, 1)
+        self.assertEqual(nb.cells[1].execution_count, 2)
+        self.assertEqual(nb.cells[1].outputs[0].output_type, 'error')
+        self.assertEqual(nb.cells[1].outputs[0].ename, 'SystemExit')
+        self.assertEqual(nb.cells[1].outputs[0].evalue, '')
+        self.assertEqual(nb.cells[2].execution_count, None)
+
+    def test_sys_exit0(self):
+        notebook_name = 'sysexit0.ipynb'
+        result_path = os.path.join(self.test_dir, 'output_{}'.format(notebook_name))
+        execute_notebook(get_notebook_path(notebook_name), result_path)
+        nb = load_notebook_node(result_path)
+        self.assertEqual(nb.cells[0].cell_type, "code")
+        self.assertEqual(nb.cells[0].execution_count, 1)
+        self.assertEqual(nb.cells[1].execution_count, 2)
+        self.assertEqual(nb.cells[1].outputs[0].output_type, 'error')
+        self.assertEqual(nb.cells[1].outputs[0].ename, 'SystemExit')
+        self.assertEqual(nb.cells[1].outputs[0].evalue, '0')
+        self.assertEqual(nb.cells[2].execution_count, None)
+
+    def test_sys_exit1(self):
+        notebook_name = 'sysexit1.ipynb'
+        result_path = os.path.join(self.test_dir, 'output_{}'.format(notebook_name))
+        with self.assertRaises(PapermillExecutionError):
+            execute_notebook(get_notebook_path(notebook_name), result_path)
+        nb = load_notebook_node(result_path)
+        self.assertEqual(nb.cells[0].cell_type, "code")
+        self.assertEqual(nb.cells[0].outputs[0].output_type, "display_data")
+        self.assertEqual(nb.cells[1].execution_count, 1)
+        self.assertEqual(nb.cells[2].execution_count, 2)
+        self.assertEqual(nb.cells[2].outputs[0].output_type, 'error')
+        self.assertEqual(nb.cells[3].execution_count, None)