Make tests a little less noisy

src/api/tests/common.py

@@ -0,0 +1,49 @@
+import os
+import logging
+
+from contextlib import contextmanager
+
+
+def get_handlers():
+    """Obtain pointers to all StreamHandlers."""
+    handlers = {}
+
+    rootlogger = logging.getLogger()
+    for h in rootlogger.handlers:
+        if isinstance(h, logging.StreamHandler):
+            handlers[h.name] = h
+
+    for logger in logging.Logger.manager.loggerDict.values():
+        if not isinstance(logger, logging.PlaceHolder):
+            for h in logger.handlers:
+                if isinstance(h, logging.StreamHandler):
+                    handlers[h.name] = h
+
+    return handlers
+
+
+@contextmanager
+def less_console_noise():
+    """
+    Context manager to use in tests to silence console logging.
+
+    This is helpful on tests which trigger console messages
+    (such as errors) which are normal and expected.
+
+    It can easily be removed to debug a failing test.
+    """
+    restore = {}
+    handlers = get_handlers()
+    devnull = open(os.devnull, "w")
+
+    # redirect all the streams
+    for handler in handlers.values():
+        prior = handler.setStream(devnull)
+        restore[handler.name] = prior
+    try:
+        # run the test
+        yield
+    finally:
+        # restore the streams
+        for handler in handlers.values():
+            handler.setStream(restore[handler.name])

src/api/tests/test_available.py

@@ -7,6 +7,7 @@ from django.contrib.auth import get_user_model
 from django.test import TestCase, RequestFactory
 
 from ..views import available, _domains, in_domains
+from .common import less_console_noise
 
 API_BASE_PATH = "/api/v1/available/"
 
@@ -104,10 +105,12 @@ class AvailableAPITest(TestCase):
 
     def test_available_post(self):
         """Cannot post to the /available/ API endpoint."""
+        with less_console_noise():
             response = self.client.post(API_BASE_PATH + "nonsense")
         self.assertEqual(response.status_code, 405)
 
     def test_available_bad_input(self):
         self.client.force_login(self.user)
+        with less_console_noise():
             response = self.client.get(API_BASE_PATH + "blah!;")
         self.assertEqual(response.status_code, 400)

src/registrar/tests/common.py

@@ -1,7 +1,57 @@
+import os
+import logging
+
+from contextlib import contextmanager
+
 from django.conf import settings
 from django.contrib.auth import get_user_model, login
 
 
+def get_handlers():
+    """Obtain pointers to all StreamHandlers."""
+    handlers = {}
+
+    rootlogger = logging.getLogger()
+    for h in rootlogger.handlers:
+        if isinstance(h, logging.StreamHandler):
+            handlers[h.name] = h
+
+    for logger in logging.Logger.manager.loggerDict.values():
+        if not isinstance(logger, logging.PlaceHolder):
+            for h in logger.handlers:
+                if isinstance(h, logging.StreamHandler):
+                    handlers[h.name] = h
+
+    return handlers
+
+
+@contextmanager
+def less_console_noise():
+    """
+    Context manager to use in tests to silence console logging.
+
+    This is helpful on tests which trigger console messages
+    (such as errors) which are normal and expected.
+
+    It can easily be removed to debug a failing test.
+    """
+    restore = {}
+    handlers = get_handlers()
+    devnull = open(os.devnull, "w")
+
+    # redirect all the streams
+    for handler in handlers.values():
+        prior = handler.setStream(devnull)
+        restore[handler.name] = prior
+    try:
+        # run the test
+        yield
+    finally:
+        # restore the streams
+        for handler in handlers.values():
+            handler.setStream(restore[handler.name])
+
+
 class MockUserLogin:
     def __init__(self, get_response):
         self.get_response = get_response
@@ -23,3 +73,5 @@ class MockUserLogin:
 
         response = self.get_response(request)
         return response
+
+