[skip changelog] Add linting and formatting for Python scripts (#832)

* [skip changelog] Added Python linting and formatting

Python linting is done using flake8 and formatting with black.
A linting workflow will run any time a Python file is modified, a format
workflow instead can be triggered by commenting in a PR.
Taskfile has been updated with lint and format tasks.

* [skip changelog] Fixed all Python linting issues

* [skip changelog] Fix Python linting and removed format workflow

Author: silvanocerza

.flake8

@@ -0,0 +1,5 @@
+# TODO: move this to pyproject.toml when supported: https://gitlab.com/pycqa/flake8/merge_requests/245
+
+[flake8]
+max-line-length = 120
+ignore = E741

.github/workflows/python-lint.yaml

@@ -0,0 +1,39 @@
+name: "Lints Python code"
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - "**.py"
+      - ".flake8"
+  pull_request:
+    paths:
+      - "**.py"
+      - ".flake8"
+
+jobs:
+  python-linting:
+    name: "Lints Python code"
+    runs-on: ubuntu-latest
+
+  steps:
+    - name: Checkout
+      uses: actions/checkout@master
+
+    - name: Install Taskfile
+      uses: Arduino/actions/setup-taskfile@master
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
+
+    - name: Activate Python
+        uses: actions/setup-python@v1
+        with:
+          python-version: '3.8'
+          architecture: 'x64'
+
+    - name: Install Poetry
+      run: pip install poetry
+
+    - name: Lints Python files
+      run: task python:check

.github/workflows/test.yaml

@@ -43,6 +43,15 @@ jobs:
         with:
           repo-token: ${{ secrets.GITHUB_TOKEN }}
 
+      - name: Install Python
+        uses: actions/setup-python@v1
+        with:
+          python-version: "3.8"
+          architecture: "x64"
+
+      - name: Install Poetry
+        run: pip install poetry
+
       - name: Check the code is good
         run: task check
 
@@ -65,16 +74,8 @@ jobs:
         if: matrix.operating-system == 'ubuntu-latest'
         run: task test-legacy
 
-      - name: Install Python
-        uses: actions/setup-python@v1
-        with:
-          python-version: '3.8'
-          architecture: 'x64'
-
       - name: Run integration tests
-        run: |
-          pip install poetry
-          task test-integration
+        run: task test-integration
 
       - name: Send unit tests coverage to Codecov
         # Since secrets aren't available on forks, we only

Taskfile.yml

@@ -104,6 +104,19 @@ tasks:
       - go vet {{ default .DEFAULT_TARGETS .TARGETS }}
       - "'{{.GOLINTBIN}}' {{.GOLINTFLAGS}} {{ default .DEFAULT_TARGETS .TARGETS }}"
       - task: i18n:check
+      - task: python:check
+
+  python:check:
+    desc: Linting for Python files
+    cmds:
+      - poetry install --no-root
+      - poetry run flake8
+
+  python:format:
+    desc: Automatically formats Python files
+    cmds:
+      - poetry install --no-root
+      - poetry run black .
 
   check-legacy:
     desc: Check fmt and lint for the `legacy` package

docs/CONTRIBUTING.md

@@ -154,6 +154,20 @@ task test-integration
 
 This will automatically install the necessary dependencies, if not already installed, and run the integration tests automatically.
 
+When editing any Python file in the project remember to run linting checks with:
+
+```shell
+task python:check
+```
+
+This will run `flake8` automatically and return any error in the code formatting, if not already installed it will also install integration tests dependencies.
+
+In case of linting errors you should be able to solve most of them by automatically formatting with:
+
+```shell
+task python:format
+```
+
 ## Working on docs
 
 Documentation is provided to final users in form of static HTML content generated

docs/build.py

@@ -100,15 +100,11 @@ def main(test, dry, remote):
     # version is the most recent
     docs_version, alias = get_docs_version(repo.active_branch.name, rel_br_names)
     if docs_version is None:
-        print(
-            f"Can't get version from current branch '{repo.active_branch}', skip docs generation"
-        )
+        print(f"Can't get version from current branch '{repo.active_branch}', skip docs generation")
         return 0
 
     # Taskfile args aren't regular args so we put everything in one string
-    cmd = (
-        f"task docs:publish DOCS_REMOTE={remote} DOCS_VERSION={docs_version} DOCS_ALIAS={alias}",
-    )
+    cmd = (f"task docs:publish DOCS_REMOTE={remote} DOCS_VERSION={docs_version} DOCS_ALIAS={alias}",)
 
     if dry:
         print(cmd)