[CI] Add nox linting

Change-Id: I2a9145031e41fe3d591a89dc2a67dcbcd02ba722

.gitignore

@@ -0,0 +1,2 @@
+__pycache__/
+.nox/

.yamllint

@@ -0,0 +1,4 @@
+extends: default
+rules:
+  document-start: disable
+  line-length: disable

noxfile.py

@@ -0,0 +1,36 @@
+import nox
+
+nox.options.error_on_external_run = True
+nox.options.reuse_existing_virtualenvs = True
+
+YAML_PATHS = [
+    "./zuul.d/",
+]
+
+PYTHON_PATHS = [
+    "./noxfile.py",
+]
+
+
+@nox.session
+def black(session):
+    session.install("black")
+    session.run("black", *PYTHON_PATHS)
+
+
+@nox.session
+def isort(session):
+    session.install("isort")
+    session.run("isort", "--profile=black", *PYTHON_PATHS)
+
+
+@nox.session
+def linters(session):
+    session.install("yamllint")
+    session.install("black")
+    session.install("isort")
+    session.install("flake8")
+    session.run("yamllint", *YAML_PATHS)
+    session.run("black", "--check", *PYTHON_PATHS)
+    session.run("isort", "--profile=black", "--check", *PYTHON_PATHS)
+    session.run("flake8", *PYTHON_PATHS)

zuul.d/project.yaml

@@ -2,9 +2,11 @@
     check:
       jobs:
         - nebulous-component-template-build-container-images
+        - nox-linters
     gate:
       jobs:
         - nebulous-component-template-upload-container-images
+        - nox-linters
     promote:
       jobs:
         - nebulous-component-template-promote-container-images