add command line option to set number of retries

--retries defaults to 3

conftest.py

@@ -106,6 +106,8 @@ def rpls(paths):
 def pytest_addoption(parser):
     parser.addoption("--config", action="append", help="path to Deckard configuration .yaml file")
     parser.addoption("--scenarios", action="append", help="directory with .rpl files")
+    parser.addoption("--retries", action="store", help=("number of retries per"
+                                                        "test when Deckard is under load"))
 
 
 def pytest_generate_tests(metafunc):
@@ -128,7 +130,11 @@ def pytest_generate_tests(metafunc):
     if 'rpl_path' in metafunc.fixturenames:
         paths = metafunc.config.option.scenarios
         metafunc.parametrize("rpl_path", rpls(paths), ids=str)
-
+    if 'max_retries' in metafunc.fixturenames:
+        max_retries = metafunc.config.option.retries
+        if max_retries is None:
+            max_retries = 3
+        metafunc.parametrize("max_retries", [max_retries], ids=str)
 
 def check_log_level_xdist(level):
     if level < logging.ERROR:

deckard_pytest.py

@@ -35,7 +35,7 @@ logging.getLogger("augeas").setLevel(logging.ERROR)
 check_platform()
 
 
-def run_test(path, qmin, config, retries=0):
+def run_test(path, qmin, config, max_retries, retries=0):
     set_coverage_env(path, qmin)
     try:
         del os.environ["SOCKET_WRAPPER_DIR"]
@@ -44,24 +44,24 @@ def run_test(path, qmin, config, retries=0):
     try:
         deckard.process_file(path, qmin, config)
     except deckard.DeckardUnderLoadError as e:
-        if retries < 3:
+        if retries < max_retries:
             logging.error("Deckard under load. Retrying…")
             # Exponential backoff
-            time.sleep((2 ** (retries + 1)) + (random.randint(0, 1000) / 1000))
-            run_test(path, qmin, config, retries + 1)
+            time.sleep((2 ** retries) + random.random())
+            run_test(path, qmin, config, max_retries, retries + 1)
         else:
             raise e
 
 
-def test_passes_qmin_on(scenario):
+def test_passes_qmin_on(scenario, max_retries):
     if scenario.qmin is True or scenario.qmin is None:
-        run_test(scenario.path, True, scenario.config)
+        run_test(scenario.path, True, scenario.config, max_retries)
     else:
         pytest.skip("Query minimization is off in test config")
 
 
-def test_passes_qmin_off(scenario):
+def test_passes_qmin_off(scenario, max_retries):
     if scenario.qmin is False or scenario.qmin is None:
-        run_test(scenario.path, False, scenario.config)
+        run_test(scenario.path, False, scenario.config, max_retries)
     else:
         pytest.skip("Query minimization is on in test config")