Add unit tests and rework API

.flake8

@@ -3,5 +3,6 @@ max-line-length = 88
 extend-exclude =
     *node_modules,
     *.serverless,
-extend-ignore = E731
+extend-ignore = E731, W503
 # E731 do not assign a lambda expression, use a def
+# W503 line break before binary operator

TODO.md

@@ -14,7 +14,7 @@
 - Fix the mess you did in iteration 1 <--- OK!
 
 ## Wave 3 - Time for the boring work
-- Add a test suite (100% coverage)
+- Add a test suite (100% coverage) <--- OK!
 - Add coverage report generation <--- OK!
 - Packaging (poetry!) <--- OK!
 - Add linters (flake8, black, isort, ~~bandit~~, ~~safety~~) <--- OK!

pylaprof/__init__.py

@@ -34,16 +34,16 @@ class FS(Storer):
 
     def __init__(self, path=None):
         """
-        path (str)
-          Where to store the report. Defaults to `pylaprof-{date}.txt` if None.
+        path (func() -> str)
+          Function to use to get report's destination path. Defaults to a generator with
+          format `pylaprof-{date}.txt` if None.
         """
         self.path = path
+        if path is None:
+            self.path = lambda: f"pylaprof-{datetime.now(timezone.utc).isoformat()}.txt"
 
     def store(self, file):
-        path = self.path
-        if path is None:
-            now = datetime.now(timezone.utc).isoformat()
-            path = f"pylaprof-{now}.txt"
+        path = self.path()
         with open(path, "w") as fp:
             shutil.copyfileobj(file, fp)
 
@@ -57,38 +57,38 @@ def __init__(
         self,
         s3_opts=None,
         bucket="pylaprof",
-        prefix="",
+        key=None,
         put_object_opts=None,
     ):
         """
         s3_opts (dict)
           Additional options to provide to boto3's `resource` method.
         bucket (string)
           Bucket where to store the report file(s).
-        prefix (string)
-          String to prepend to report files.
+        key (func() -> str)
+          Function to use to get report's object key. Defaults to a generator with
+          format `{randstr}-{date}.txt` if None.
         put_object_opts (dict)
           Additional options to provide to bucket's `put_object` method.
-
-        Report files will be stored as `{prefix}{randstr}-{date}.txt`, with `randstr`
-        being a random string of 8 characters.
         """
         if s3_opts is None:
             s3_opts = {}
         s3 = boto3.resource("s3", **s3_opts)
 
         self.bucket = s3.Bucket(bucket)
 
-        self.prefix = prefix
+        self.key = key
+        if key is None:
+            self.key = (
+                lambda: f"{str(uuid.uuid4())[:8]}-{datetime.now(timezone.utc).isoformat()}.txt"  # noqa
+            )
 
         self.put_object_opts = {}
         if put_object_opts is not None:
             self.put_object_opts = put_object_opts
 
     def store(self, file):
-        randstr = str(uuid.uuid4())[:8]
-        now = datetime.now(timezone.utc).isoformat()
-        key = f"{self.prefix}{randstr}-{now}.txt"
+        key = self.key()
         self.bucket.put_object(Body=file.read(), Key=key, **self.put_object_opts)
 
 
@@ -151,7 +151,7 @@ def __init__(self, period=0.01, single=True, min_time=0, sampler=None, storer=No
         single (bool)
           Profile only the thread which created this instance.
         min_time (int)
-          Store profiling data only if execution lasts more than this amount of time.
+          Store profiling data only if execution lasts more than this amount of seconds.
         sampler (Sampler)
           Sampler to use to process stack frames.
           Defaults to an instance of `StackCollapse` if None.
@@ -183,7 +183,7 @@ def __init__(self, period=0.01, single=True, min_time=0, sampler=None, storer=No
             sampler = StackCollapse()
         self.sampler = sampler
 
-        self._can_run = False
+        self._can_run = False  # Variable to control profiler's main loop.
         self._stop_event = threading.Event()
         self.daemon = True
         self.clean_exit = False
@@ -198,9 +198,8 @@ def stop(self):
         Request thread to stop.
         Does not wait for actual termination (use join() method).
         """
-        if self.is_alive():
-            self._can_run = False
-            self._stop_event.set()
+        self._can_run = False
+        self._stop_event.set()
 
     def __enter__(self):
         self.start()

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "pylaprof"
-version = "0.3.0"
+version = "0.3.1"
 description = "A Python sampling profiler for AWS Lambda functions (and not only)."
 authors = ["Giuseppe Lumia <[email protected]>"]
 license = "MIT"
@@ -18,6 +18,7 @@ black = "^21.10b0"
 isort = "^5.10.1"
 pytest = "^6.2.5"
 coverage = {version = "^6.1.2", extras = ["toml"]}
+freezegun = "^1.1.0"
 
 [tool.poetry.scripts]
 pylaprof-merge = "scripts.merge:main"

tests/conftest.py

@@ -0,0 +1,23 @@
+import os
+import tempfile
+from unittest.mock import Mock
+
+import pytest
+
+
+@pytest.fixture
+def tmpcwd():
+    """Run test in a temporary directory."""
+    cwd = os.getcwd()
+    with tempfile.TemporaryDirectory(prefix="pylaprof-test") as tmpdir:
+        os.chdir(tmpdir)
+        yield
+    os.chdir(cwd)
+
+
+@pytest.fixture
+def boto3_mock(monkeypatch):
+    """Monkeypatch pylaprof's boto3 module."""
+    mock = Mock()
+    monkeypatch.setattr("pylaprof.boto3", mock)
+    return mock

tests/dummy-report.txt

@@ -0,0 +1,5 @@
+<module> (/home/gius/pylaprof/tests/launcher.py:33);__enter__ (/home/gius/pylaprof/tests/pylaprof/__init__.py:210);start (/home/gius/pylaprof/tests/pylaprof/__init__.py:198);start (/usr/lib/python3.9/threading.py:897);wait (/usr/lib/python3.9/threading.py:574);wait (/usr/lib/python3.9/threading.py:312) 1
+<module> (/home/gius/pylaprof/tests/launcher.py:34);main (/home/gius/pylaprof/tests/launcher.py:15);handler (/home/gius/pylaprof/tests/handler.py:8);sleepy_task (/home/gius/pylaprof/tests/handler.py:16) 290
+<module> (/home/gius/pylaprof/tests/launcher.py:34);main (/home/gius/pylaprof/tests/launcher.py:15);handler (/home/gius/pylaprof/tests/handler.py:9);cpu_intens_task (/home/gius/pylaprof/tests/handler.py:22) 129
+<module> (/home/gius/pylaprof/tests/launcher.py:34);main (/home/gius/pylaprof/tests/launcher.py:15);handler (/home/gius/pylaprof/tests/handler.py:9);cpu_intens_task (/home/gius/pylaprof/tests/handler.py:21) 33
+<module> (/home/gius/pylaprof/tests/launcher.py:34);main (/home/gius/pylaprof/tests/launcher.py:15);handler (/home/gius/pylaprof/tests/handler.py:10);io_task (/home/gius/pylaprof/tests/handler.py:26);get (/home/gius/.local/lib/python3.9/site-packages/requests/api.py:76);request (/home/gius/.local/lib/python3.9/site-packages/requests/api.py:61);request (/home/gius/.local/lib/python3.9/site-packages/requests/sessions.py:542);send (/home/gius/.local/lib/python3.9/site-packages/requests/sessions.py:655);send (/home/gius/.local/lib/python3.9/site-packages/requests/adapters.py:439);urlopen (/usr/lib/python3.9/site-packages/urllib3/connectionpool.py:699);_make_request (/usr/lib/python3.9/site-packages/urllib3/connectionpool.py:440);getresponse (/usr/lib/python3.9/http/client.py:1371);begin (/usr/lib/python3.9/http/client.py:319);_read_status (/usr/lib/python3.9/http/client.py:280);readinto (/usr/lib/python3.9/socket.py:704) 290