Ran black code formatter on everything.
[python_utils.git] / unittest_utils.py
index 270e20d1e268112f543ac70d4e096745b1861d1c..4a9669d3a21f66e35004e1968cc85b65d711fd5c 100644 (file)
@@ -7,27 +7,33 @@
    caveat emptor.
 """
 
+from abc import ABC, abstractmethod
 import contextlib
 import functools
 import inspect
 import logging
+import os
 import pickle
 import random
 import statistics
 import time
 import tempfile
-from typing import Callable
+from typing import Callable, Dict, List
 import unittest
 import warnings
 
 import bootstrap
 import config
+import function_utils
+import scott_secrets
+
+import sqlalchemy as sa
 
 
 logger = logging.getLogger(__name__)
 cfg = config.add_commandline_args(
-    f'Logging ({__file__})',
-    'Args related to function decorators')
+    f'Logging ({__file__})', 'Args related to function decorators'
+)
 cfg.add_argument(
     '--unittests_ignore_perf',
     action='store_true',
@@ -37,23 +43,113 @@ cfg.add_argument(
 cfg.add_argument(
     '--unittests_num_perf_samples',
     type=int,
-    default=20,
-    help='The count of perf timing samples we need to see before blocking slow runs on perf grounds'
+    default=50,
+    help='The count of perf timing samples we need to see before blocking slow runs on perf grounds',
 )
 cfg.add_argument(
     '--unittests_drop_perf_traces',
     type=str,
     nargs=1,
     default=None,
-    help='The identifier (i.e. file!test_fixture) for which we should drop all perf data'
+    help='The identifier (i.e. file!test_fixture) for which we should drop all perf data',
+)
+cfg.add_argument(
+    '--unittests_persistance_strategy',
+    choices=['FILE', 'DATABASE'],
+    default='DATABASE',
+    help='Should we persist perf data in a file or db?',
+)
+cfg.add_argument(
+    '--unittests_perfdb_filename',
+    type=str,
+    metavar='FILENAME',
+    default=f'{os.environ["HOME"]}/.python_unittest_performance_db',
+    help='File in which to store perf data (iff --unittests_persistance_strategy is FILE)',
+)
+cfg.add_argument(
+    '--unittests_perfdb_spec',
+    type=str,
+    metavar='DBSPEC',
+    default='mariadb+pymysql://python_unittest:<PASSWORD>@db.house:3306/python_unittest_performance',
+    help='Db connection spec for perf data (iff --unittest_persistance_strategy is DATABASE)',
 )
-
 
 # >>> This is the hacky business, FYI. <<<
 unittest.main = bootstrap.initialize(unittest.main)
 
 
-_db = '/home/scott/.python_unittest_performance_db'
+class PerfRegressionDataPersister(ABC):
+    def __init__(self):
+        pass
+
+    @abstractmethod
+    def load_performance_data(self) -> Dict[str, List[float]]:
+        pass
+
+    @abstractmethod
+    def save_performance_data(
+        self, method_id: str, data: Dict[str, List[float]]
+    ):
+        pass
+
+    @abstractmethod
+    def delete_performance_data(self, method_id: str):
+        pass
+
+
+class FileBasedPerfRegressionDataPersister(PerfRegressionDataPersister):
+    def __init__(self, filename: str):
+        self.filename = filename
+        self.traces_to_delete = []
+
+    def load_performance_data(self, method_id: str) -> Dict[str, List[float]]:
+        with open(self.filename, 'rb') as f:
+            return pickle.load(f)
+
+    def save_performance_data(
+        self, method_id: str, data: Dict[str, List[float]]
+    ):
+        for trace in self.traces_to_delete:
+            if trace in data:
+                data[trace] = []
+
+        with open(self.filename, 'wb') as f:
+            pickle.dump(data, f, pickle.HIGHEST_PROTOCOL)
+
+    def delete_performance_data(self, method_id: str):
+        self.traces_to_delete.append(method_id)
+
+
+class DatabasePerfRegressionDataPersister(PerfRegressionDataPersister):
+    def __init__(self, dbspec: str):
+        self.dbspec = dbspec
+        self.engine = sa.create_engine(self.dbspec)
+        self.conn = self.engine.connect()
+
+    def load_performance_data(self, method_id: str) -> Dict[str, List[float]]:
+        results = self.conn.execute(
+            sa.text(
+                f'SELECT * FROM runtimes_by_function WHERE function = "{method_id}";'
+            )
+        )
+        ret = {method_id: []}
+        for result in results.all():
+            ret[method_id].append(result['runtime'])
+        results.close()
+        return ret
+
+    def save_performance_data(
+        self, method_id: str, data: Dict[str, List[float]]
+    ):
+        self.delete_performance_data(method_id)
+        for (method_id, perf_data) in data.items():
+            sql = 'INSERT INTO runtimes_by_function (function, runtime) VALUES '
+            for perf in perf_data:
+                self.conn.execute(sql + f'("{method_id}", {perf});')
+
+    def delete_performance_data(self, method_id: str):
+        sql = f'DELETE FROM runtimes_by_function WHERE function = "{method_id}"'
+        self.conn.execute(sql)
 
 
 def check_method_for_perf_regressions(func: Callable) -> Callable:
@@ -65,84 +161,108 @@ def check_method_for_perf_regressions(func: Callable) -> Callable:
     message if it has become too slow.
 
     """
-    def load_known_test_performance_characteristics():
-        with open(_db, 'rb') as f:
-            return pickle.load(f)
-
-    def save_known_test_performance_characteristics(perfdb):
-        with open(_db, 'wb') as f:
-            pickle.dump(perfdb, f, pickle.HIGHEST_PROTOCOL)
 
     @functools.wraps(func)
     def wrapper_perf_monitor(*args, **kwargs):
+        if config.config['unittests_persistance_strategy'] == 'FILE':
+            filename = config.config['unittests_perfdb_filename']
+            helper = FileBasedPerfRegressionDataPersister(filename)
+        elif config.config['unittests_persistance_strategy'] == 'DATABASE':
+            dbspec = config.config['unittests_perfdb_spec']
+            dbspec = dbspec.replace(
+                '<PASSWORD>', scott_secrets.MARIADB_UNITTEST_PERF_PASSWORD
+            )
+            helper = DatabasePerfRegressionDataPersister(dbspec)
+        else:
+            raise Exception(
+                'Unknown/unexpected --unittests_persistance_strategy value'
+            )
+
+        func_id = function_utils.function_identifier(func)
+        func_name = func.__name__
+        logger.debug(f'Watching {func_name}\'s performance...')
+        logger.debug(f'Canonical function identifier = {func_id}')
+
         try:
-            perfdb = load_known_test_performance_characteristics()
+            perfdb = helper.load_performance_data(func_id)
         except Exception as e:
             logger.exception(e)
-            msg = f'Unable to load perfdb from {_db}'
+            msg = 'Unable to load perfdb; skipping it...'
             logger.warning(msg)
             warnings.warn(msg)
             perfdb = {}
 
-        # This is a unique identifier for a test: filepath!function
-        logger.debug(f'Watching {func.__name__}\'s performance...')
-        func_id = f'{func.__globals__["__file__"]}!{func.__name__}'
-        logger.debug(f'Canonical function identifier = {func_id}')
-
         # cmdline arg to forget perf traces for function
         drop_id = config.config['unittests_drop_perf_traces']
         if drop_id is not None:
-            if drop_id in perfdb:
-                perfdb[drop_id] = []
+            helper.delete_performance_data(drop_id)
 
         # Run the wrapped test paying attention to latency.
         start_time = time.perf_counter()
         value = func(*args, **kwargs)
         end_time = time.perf_counter()
         run_time = end_time - start_time
-        logger.debug(f'{func.__name__} executed in {run_time:f}s.')
 
-        # Check the db; see if it was unexpectedly slow.
+        # See if it was unexpectedly slow.
         hist = perfdb.get(func_id, [])
         if len(hist) < config.config['unittests_num_perf_samples']:
             hist.append(run_time)
-            logger.debug(
-                f'Still establishing a perf baseline for {func.__name__}'
-            )
+            logger.debug(f'Still establishing a perf baseline for {func_name}')
         else:
             stdev = statistics.stdev(hist)
-            limit = hist[-1] + stdev * 5
+            logger.debug(f'For {func_name}, performance stdev={stdev}')
+            slowest = hist[-1]
+            logger.debug(
+                f'For {func_name}, slowest perf on record is {slowest:f}s'
+            )
+            limit = slowest + stdev * 4
             logger.debug(
-                f'Max acceptable performace for {func.__name__} is {limit:f}s'
+                f'For {func_name}, max acceptable runtime is {limit:f}s'
             )
-            if (
-                run_time > limit and
-                not config.config['unittests_ignore_perf']
-            ):
+            logger.debug(
+                f'For {func_name}, actual observed runtime was {run_time:f}s'
+            )
+            if run_time > limit and not config.config['unittests_ignore_perf']:
                 msg = f'''{func_id} performance has regressed unacceptably.
-{hist[-1]:f}s is the slowest record in {len(hist)} db perf samples.
-It just ran in {run_time:f}s which is >5 stdevs slower than the slowest sample.
+{slowest:f}s is the slowest runtime on record in {len(hist)} perf samples.
+It just ran in {run_time:f}s which is 4+ stdevs slower than the slowest.
 Here is the current, full db perf timing distribution:
 
 '''
                 for x in hist:
                     msg += f'{x:f}\n'
                 logger.error(msg)
-                slf = args[0]
-                slf.fail(msg)
+                slf = args[0]  # Peek at the wrapped function's self ref.
+                slf.fail(msg)  # ...to fail the testcase.
             else:
                 hist.append(run_time)
 
+        # Don't spam the database with samples; just pick a random
+        # sample from what we have and store that back.
         n = min(config.config['unittests_num_perf_samples'], len(hist))
         hist = random.sample(hist, n)
         hist.sort()
         perfdb[func_id] = hist
-        save_known_test_performance_characteristics(perfdb)
+        helper.save_performance_data(func_id, perfdb)
         return value
+
     return wrapper_perf_monitor
 
 
 def check_all_methods_for_perf_regressions(prefix='test_'):
+    """Decorate unittests with this to pay attention to the perf of the
+    testcode and flag perf regressions.  e.g.
+
+    import unittest_utils as uu
+
+    @uu.check_all_methods_for_perf_regressions()
+    class TestMyClass(unittest.TestCase):
+
+        def test_some_part_of_my_class(self):
+            ...
+
+    """
+
     def decorate_the_testcase(cls):
         if issubclass(cls, unittest.TestCase):
             for name, m in inspect.getmembers(cls, inspect.isfunction):
@@ -150,12 +270,14 @@ def check_all_methods_for_perf_regressions(prefix='test_'):
                     setattr(cls, name, check_method_for_perf_regressions(m))
                     logger.debug(f'Wrapping {cls.__name__}:{name}.')
         return cls
+
     return decorate_the_testcase
 
 
 def breakpoint():
     """Hard code a breakpoint somewhere; drop into pdb."""
     import pdb
+
     pdb.set_trace()
 
 
@@ -234,4 +356,5 @@ class RecordMultipleStreams(object):
 
 if __name__ == '__main__':
     import doctest
+
     doctest.testmod()