diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index 6fb2d697..8ed660b9 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -1,5 +1,23 @@
 # Release History
 
+## 2.4.9 (2019-12-29)
+
+**Added**
+
+- test: add unittest for cli
+
+**Changed**
+
+- change: html report name defaults to be in UTC ISO 8601 format
+
+**Fixed**
+
+- fix: display validators in report when validate raised exception
+- fix: eval validator python script before validating
+- fix: do not strip string content when preparing lazy data
+- fix: catch ApiNotFound exception when loading testcases
+- fix: print exception string with exception stage
+
 ## 2.4.8 (2019-12-25)
 
 **Added**
diff --git a/httprunner/__init__.py b/httprunner/__init__.py
index 1766552f..13d3adf4 100644
--- a/httprunner/__init__.py
+++ b/httprunner/__init__.py
@@ -1,4 +1,4 @@
-__version__ = "2.4.8"
+__version__ = "2.4.9"
 __description__ = "One-stop solution for HTTP(S) testing."
 
 __all__ = ["__version__", "__description__"]
diff --git a/httprunner/cli.py b/httprunner/cli.py
index 50e365d5..8258ba4f 100644
--- a/httprunner/cli.py
+++ b/httprunner/cli.py
@@ -105,6 +105,7 @@ def main():
             err_code |= (0 if summary and summary["success"] else 1)
     except Exception as ex:
         color_print("!!!!!!!!!! exception stage: {} !!!!!!!!!!".format(runner.exception_stage), "YELLOW")
+        color_print(str(ex), "RED")
         capture_exception(ex)
         err_code = 1
 
diff --git a/httprunner/compat.py b/httprunner/compat.py
index e7e92ca3..aa2a16ec 100644
--- a/httprunner/compat.py
+++ b/httprunner/compat.py
@@ -47,6 +47,7 @@ if is_py2:
     integer_types = (int, long)
 
     FileNotFoundError = IOError
+    import StringIO as io
 
 elif is_py3:
     builtin_str = str
@@ -57,3 +58,4 @@ elif is_py3:
     integer_types = (int,)
 
     FileNotFoundError = FileNotFoundError
+    import io as io
diff --git a/httprunner/loader/buildup.py b/httprunner/loader/buildup.py
index e92739ea..b6839b93 100644
--- a/httprunner/loader/buildup.py
+++ b/httprunner/loader/buildup.py
@@ -480,6 +480,8 @@ def load_cases(path, dot_env_path=None):
         loaded_content = None
         try:
             loaded_content = load_test_file(path)
+        except exceptions.ApiNotFound as ex:
+            logger.log_warning("Invalid api reference in {}: {}".format(path, ex))
         except exceptions.FileFormatError:
             logger.log_warning("Invalid test file format: {}".format(path))
 
diff --git a/httprunner/parser.py b/httprunner/parser.py
index d5ef8214..8fc49d8e 100644
--- a/httprunner/parser.py
+++ b/httprunner/parser.py
@@ -776,7 +776,6 @@ def prepare_lazy_data(content, functions_mapping=None, check_variables_set=None,
 
         functions_mapping = functions_mapping or {}
         check_variables_set = check_variables_set or set()
-        content = content.strip()
         content = LazyString(content, functions_mapping, check_variables_set, cached)
 
     return content
diff --git a/httprunner/report/html/gen_report.py b/httprunner/report/html/gen_report.py
index 265acdea..303abd63 100644
--- a/httprunner/report/html/gen_report.py
+++ b/httprunner/report/html/gen_report.py
@@ -33,15 +33,16 @@ def gen_html_report(summary, report_template=None, report_dir=None, report_file=
 
     logger.log_info("Start to render Html report ...")
 
-    start_at_timestamp = int(summary["time"]["start_at"])
-    summary["time"]["start_datetime"] = datetime.fromtimestamp(start_at_timestamp).strftime('%Y-%m-%d %H:%M:%S')
+    start_at_timestamp = summary["time"]["start_at"]
+    utc_time_iso_8601_str = datetime.utcfromtimestamp(start_at_timestamp).isoformat()
+    summary["time"]["start_datetime"] = utc_time_iso_8601_str
 
     if report_file:
         report_dir = os.path.dirname(report_file)
         report_file_name = os.path.basename(report_file)
     else:
         report_dir = report_dir or os.path.join(os.getcwd(), "reports")
-        report_file_name = "{}.html".format(int(start_at_timestamp * 1000))
+        report_file_name = "{}.html".format(utc_time_iso_8601_str)
 
     if not os.path.isdir(report_dir):
         os.makedirs(report_dir)
diff --git a/httprunner/runner.py b/httprunner/runner.py
index 86804722..b2d1b2f3 100644
--- a/httprunner/runner.py
+++ b/httprunner/runner.py
@@ -303,8 +303,8 @@ class Runner(object):
         except exceptions.ValidationFailure:
             log_req_resp_details()
             raise
-
-        return validator.validation_results
+        finally:
+            self.validation_results = validator.validation_results
 
     def _run_testcase(self, testcase_dict):
         """ run single testcase.
@@ -382,9 +382,9 @@ class Runner(object):
             self._run_testcase(test_dict)
         else:
             # api
-            validation_results = {}
+            self.validation_results = {}
             try:
-                validation_results = self._run_test(test_dict)
+                self._run_test(test_dict)
             except Exception:
                 # log exception request_type and name for locust stat
                 self.exception_request_type = test_dict["request"]["method"]
@@ -393,7 +393,7 @@ class Runner(object):
             finally:
                 # get request/response data and validate results
                 self.meta_datas = getattr(self.http_client_session, "meta_data", {})
-                self.meta_datas["validators"] = validation_results
+                self.meta_datas["validators"] = self.validation_results
 
     def export_variables(self, output_variables_list):
         """ export current testcase variables
diff --git a/httprunner/validator.py b/httprunner/validator.py
index 3a821047..8dad5ac6 100644
--- a/httprunner/validator.py
+++ b/httprunner/validator.py
@@ -124,7 +124,8 @@ except Exception as ex:
         for validator in validators:
 
             if isinstance(validator, dict) and validator.get("type") == "python_script":
-                validator_dict, ex = self.validate_script(validator["script"])
+                script = self.session_context.eval_content(validator["script"])
+                validator_dict, ex = self.validate_script(script)
                 if ex:
                     validate_pass = False
                     failures.append(ex)
diff --git a/pyproject.toml b/pyproject.toml
index e0b6f378..2dfa8519 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "httprunner"
-version = "2.4.8"
+version = "2.4.9"
 description = "One-stop solution for HTTP(S) testing."
 license = "Apache-2.0"
 readme = "README.md"
diff --git a/tests/test_cli.py b/tests/test_cli.py
new file mode 100644
index 00000000..abf2a714
--- /dev/null
+++ b/tests/test_cli.py
@@ -0,0 +1,37 @@
+import sys
+import unittest
+
+from httprunner.cli import main
+from httprunner.compat import io
+
+
+class TestCli(unittest.TestCase):
+
+    def setUp(self):
+        self.captured_output = io.StringIO()
+        sys.stdout = self.captured_output
+
+    def tearDown(self):
+        sys.stdout = sys.__stdout__  # Reset redirect.
+
+    def test_show_version(self):
+        sys.argv = ["hrun", "-V"]
+
+        with self.assertRaises(SystemExit) as cm:
+            main()
+
+        self.assertEqual(cm.exception.code, 0)
+
+        from httprunner import __version__
+        self.assertIn(__version__, self.captured_output.getvalue().strip())
+
+    def test_show_help(self):
+        sys.argv = ["hrun", "-h"]
+
+        with self.assertRaises(SystemExit) as cm:
+            main()
+
+        self.assertEqual(cm.exception.code, 0)
+
+        from httprunner import __description__
+        self.assertIn(__description__, self.captured_output.getvalue().strip())