Add pep8 check to tox and GitHub actions

.github/workflows/run-tox.yml

@@ -23,3 +23,15 @@ jobs:
         run: pip install tox
       - name: Run Tox
         run: tox -e py
+  pep8:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Setup python
+        uses: actions/setup-python@v2
+        with:
+          python-version: 3.9
+      - name: Install Tox
+        run: pip install tox
+      - name: Run Tox pep8
+        run: "tox -e pep8"

tox.ini

@@ -1,9 +1,19 @@
 [tox]
-envlist = py27,py36,py37,py38,py39
+envlist = py27,py36,py37,py38,py39,pep8
 
 [testenv]
 deps =
         pathlib2; python_version<"3"
         pytest
         requests
+        flake8
 commands = pytest -v --tb=short {posargs}
+
+[testenv:pep8]
+commands = flake8 servefile/ {posargs}
+
+[flake8]
+show-source = True
+max-line-length = 120
+ignore = E123,E125,E241,E402,E741,W503,W504,H301
+exclude=.venv,.git,.tox,dist,doc,*lib/python*,*egg,build