Clean up invoke tasks (scrapd#173)

* Create a utility function to manage venvs.
* Reorganize/rename in order to simplify reusing the tasks/sessions.

Author: rgreinho

.github/CONTRIBUTING.rst

@@ -114,7 +114,7 @@ The profiling for the project is mostly done using `pyinstrument`_
 
 You can use the nox task to run the profiler automatically::
 
-  nox -s profiling
+  inv profile
 
 Additionally, you can also generate a flame graph with `py-spy`_. It requires root permissions, therefore must be run
 with sudo and will prompt you for your password::

noxfile.py

@@ -72,19 +72,6 @@ def lint_format(session):
     run_yapf(session, diff=True)
 
 
-@nox.session()
-def profiling(session):
-    """Setup the developper environment."""
-    # Install dependencies.
-    session.install('--upgrade', 'pip', 'setuptools')
-    session.install('-r', 'requirements-profilers.txt')
-    session.install('-e', '.')
-
-    env_dir = Path(session.bin)
-    scrapd = env_dir / 'scrapd'
-    session.run("pyinstrument", "--renderer", "html", f'{scrapd.resolve()}', "-v", "--format", "count", "--pages", "5")
-
-
 @nox.session()
 def pydocstyle(session):
     """Check the docstrings."""

requirements-dev.txt

@@ -5,7 +5,9 @@ aioresponses==0.6.0
 asynctest==0.12.4
 bpython
 flake8==3.7.7
+py-spy==0.1.11
 pydocstyle==3.0.0
+pyinstrument==3.0.3
 pylint==2.3.1
 pytest-asyncio==0.10.0
 pytest-bdd==3.1.0

requirements-profilers.txt

@@ -4,7 +4,7 @@ summary = Extract data from APD news site
 description-file =
   README.rst
 author = Rémy Greinhofer
-author-email = [email protected]
+author-email = [email protected]
 home-page = https://www.scrapd.org
 classifier =
   Development Status :: 5 - Production/Stable

setup.cfg

@@ -4,6 +4,7 @@
 from nox.virtualenv import VirtualEnv
 
 # Configuration values.
+VENV = 'venv'
 project_name = 'scrapd'
 docker_org = 'scrapd'
 docker_repo = f'{docker_org}/{project_name}'
@@ -39,12 +40,10 @@ def clean_repo(c):
 
 @task
 def flame_graph(c):
-    c.run(f'nox --install-only -s profiling')
-    location = Path('.nox/profiling')
-    venv = VirtualEnv(location.resolve())
-    venv_bin = Path(venv.bin)
-    scrapd = venv_bin / 'scrapd'
-    c.run(f'sudo py-spy -d 20 --flame profile.svg -- {scrapd.resolve()} -v --pages 5')
+    """Create an interactive CPU flame graph."""
+    _, venv_bin, _ = get_venv(VENV)
+    pyspy = venv_bin / 'py-spy'
+    c.run(f'sudo {pyspy.resolve()} -d 20 --flame profile.svg -- {(venv_bin /project_name ).resolve()} -v --pages 5')
 
 
 @task
@@ -56,6 +55,15 @@ def nox(c, s=''):
         c.run(f'nox -s {s}')
 
 
+@task
+def profile(c):
+    """Create an interactive CPU flame graph."""
+    _, venv_bin, _ = get_venv(VENV)
+    pyinstrument = venv_bin / 'pyinstrument'
+    c.run(f'{pyinstrument.resolve()} --renderer html {(venv_bin /project_name ).resolve()} -v --format count --pages 5',
+          pty=True)
+
+
 @task
 def publish(c):
     """Publish the documentation."""
@@ -66,3 +74,19 @@ def publish(c):
 def setup(c):
     """Setup the developper environment."""
     c.run('nox --envdir .')
+
+
+def get_venv(venv):
+    """
+    Return `Path` objects from the venv.
+
+    :param str venv: venv name
+    :return: the venv `Path`, the `bin` folder `Path` within the venv, and if specified, the `Path` object of the
+        activate script within the venv.
+    :rtype: a tuple of 3 `Path` objects.
+    """
+    location = Path(venv)
+    venv = VirtualEnv(location.resolve())
+    venv_bin = Path(venv.bin)
+    activate = venv_bin / 'activate'
+    return venv, venv_bin, activate