Add linting to CI.

.github/workflows/lint.yml

@@ -0,0 +1,33 @@
+name: API Lint
+on:
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+
+      - uses: actions/setup-python@v2
+        name: Install Python
+        with:
+          python-version: '3.9'
+
+      - name: Pip cache
+        id: pip-cache
+        uses: actions/cache@v2
+        with:
+          path: ${{ env.pythonLocation }}
+          key: api-lint-${{ runner.os }}-${{ env.pythonLocation }}-pip-${{ hashFiles('**/requirements.txt') }}-${{ hashFiles('**/requirements-dev.txt') }}
+
+      - name: Install deps
+        if: steps.pip-cache.outputs.cache-hit != 'true'
+        run: |
+          cd api
+          python -m pip install --upgrade pip
+          python -m pip install -r requirements.txt
+          python -m pip install -r requirements-dev.txt
+
+      - name: Run linting
+        run: |
+          sh ./scripts/lint.sh

scripts/lint.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+
+set -ex
+
+mypy .
+npx -q [email protected] .
+ruff check .
+ruff format --check .