Chore: Enable mypy checking in CI (#11991)

.dockerignore

@@ -28,3 +28,4 @@
 ./resources
 # Other stuff
 **/*.drawio.png
+.mypy_baseline

.github/workflows/ci-backend.yml

@@ -99,3 +99,47 @@ jobs:
         run: |
           docker compose --file docker/compose/docker-compose.ci-test.yml logs
           docker compose --file docker/compose/docker-compose.ci-test.yml down
+  typing:
+    name: Check project typing
+    runs-on: ubuntu-24.04
+    env:
+      DEFAULT_PYTHON: "3.12"
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6.0.1
+      - name: Set up Python
+        id: setup-python
+        uses: actions/setup-python@v6.2.0
+        with:
+          python-version: "${{ env.DEFAULT_PYTHON }}"
+      - name: Install uv
+        uses: astral-sh/setup-uv@v7.2.1
+        with:
+          version: ${{ env.DEFAULT_UV_VERSION }}
+          enable-cache: true
+          python-version: ${{ steps.setup-python.outputs.python-version }}
+      - name: Install Python dependencies
+        run: |
+          uv sync \
+            --python ${{ steps.setup-python.outputs.python-version }} \
+            --group testing \
+            --group typing \
+            --frozen
+      - name: List installed Python dependencies
+        run: |
+          uv pip list
+      - name: Cache Mypy
+        uses: actions/cache@v5.0.3
+        with:
+          path: .mypy_cache
+          # Keyed by OS, Python version, and dependency hashes
+          key: ${{ runner.os }}-mypy-py${{ env.DEFAULT_PYTHON }}-${{ hashFiles('pyproject.toml', 'uv.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-mypy-py${{ env.DEFAULT_PYTHON }}-
+            ${{ runner.os }}-mypy-
+      - name: Check typing
+        run: |
+          uv run mypy \
+            --show-error-codes \
+            --warn-unused-configs \
+            src/ | uv run mypy-baseline filter

pyproject.toml

@@ -138,7 +138,9 @@ typing = [
   "django-stubs[compatible-mypy]",
   "djangorestframework-stubs[compatible-mypy]",
   "lxml-stubs",
+  "microsoft-python-type-stubs @ git+https://github.com/microsoft/python-type-stubs.git",
   "mypy",
+  "mypy-baseline",
   "types-bleach",
   "types-colorama",
   "types-dateparser",
@@ -333,10 +335,6 @@ exclude_also = [
 
 [tool.mypy]
 mypy_path = "src"
-files = [
-  "src/documents/plugins/date_parsing",
-  "src/documents/tests/date_parsing",
-]
 plugins = [
   "mypy_django_plugin.main",
   "mypy_drf_plugin.main",
@@ -348,28 +346,9 @@ disallow_untyped_defs = true
 warn_redundant_casts = true
 warn_unused_ignores = true
 
-# This prevents errors from imports, but allows type-checking logic to work
-follow_imports = "silent"
-
-[[tool.mypy.overrides]]
-module = [
-  "documents.*",
-  "paperless.*",
-  "paperless_ai.*",
-  "paperless_mail.*",
-  "paperless_tesseract.*",
-  "paperless_remote.*",
-  "paperless_text.*",
-  "paperless_tika.*",
-]
-ignore_errors = true
-
-[[tool.mypy.overrides]]
-module = [
-  "documents.plugins.date_parsing.*",
-  "documents.tests.date_parsing.*",
-]
-ignore_errors = false
-
 [tool.django-stubs]
 django_settings_module = "paperless.settings"
+
+[tool.mypy-baseline]
+baseline_path = ".mypy-baseline.txt"
+sort_baseline = true

uv.lock

@@ -1305,7 +1305,7 @@ name = "exceptiongroup"
 version = "1.3.1"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
-    { name = "typing-extensions", marker = "(python_full_version < '3.13' and platform_machine != 'aarch64' and platform_machine != 'x86_64' and sys_platform == 'linux') or (python_full_version < '3.12' and platform_machine == 'aarch64' and sys_platform == 'linux') or (python_full_version < '3.12' and platform_machine == 'x86_64' and sys_platform == 'linux') or (python_full_version < '3.13' and sys_platform == 'darwin')" },
+    { name = "typing-extensions", marker = "(python_full_version < '3.11' and sys_platform == 'darwin') or (python_full_version < '3.11' and sys_platform == 'linux')" },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/50/79/66800aadf48771f6b62f7eb014e352e5d06856655206165d775e675a02c9/exceptiongroup-1.3.1.tar.gz", hash = "sha256:8b412432c6055b0b7d14c310000ae93352ed6754f70fa8f7c34141f91c4e3219", size = 30371, upload-time = "2025-11-21T23:01:54.787Z" }
 wheels = [
@@ -2584,6 +2584,11 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/2c/19/04f9b178c2d8a15b076c8b5140708fa6ffc5601fb6f1e975537072df5b2a/mergedeep-1.3.4-py3-none-any.whl", hash = "sha256:70775750742b25c0d8f36c55aed03d24c3384d17c951b3175d898bd778ef0307", size = 6354, upload-time = "2021-02-05T18:55:29.583Z" },
 ]
 
+[[package]]
+name = "microsoft-python-type-stubs"
+version = "0"
+source = { git = "https://github.com/microsoft/python-type-stubs.git#692c37c3969d22612b295ddf7e7af5907204a386" }
+
 [[package]]
 name = "mkdocs"
 version = "1.6.1"
@@ -2875,6 +2880,15 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/8d/f4/4ce9a05ce5ded1de3ec1c1d96cf9f9504a04e54ce0ed55cfa38619a32b8d/mypy-1.19.1-py3-none-any.whl", hash = "sha256:f1235f5ea01b7db5468d53ece6aaddf1ad0b88d9e7462b86ef96fe04995d7247", size = 2471239, upload-time = "2025-12-15T05:03:07.248Z" },
 ]
 
+[[package]]
+name = "mypy-baseline"
+version = "0.7.3"
+source = { registry = "https://pypi.org/simple" }
+sdist = { url = "https://files.pythonhosted.org/packages/65/2a/03288dab6d5f24d187ba0c223f6b3035d9a29de3dd31a3e105a0d4f1b5da/mypy_baseline-0.7.3.tar.gz", hash = "sha256:325f0695310eb8f5c0f10fa7af36ee1b3785a9d26b886a61c07b4a8eddb28d29", size = 319108, upload-time = "2025-05-30T08:43:00.629Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/1f/93/7780302b206a8e8e767ce763ef06159725d1323acbe55e46a1cd1ffd109d/mypy_baseline-0.7.3-py3-none-any.whl", hash = "sha256:bd7fa899e687d75af2e3f392a9d6d1790e65dae3d31fe12525cc14f26d866b74", size = 17868, upload-time = "2025-05-30T08:42:58.262Z" },
+]
+
 [[package]]
 name = "mypy-extensions"
 version = "1.1.0"
@@ -3293,7 +3307,9 @@ typing = [
     { name = "django-stubs", extra = ["compatible-mypy"], marker = "sys_platform == 'darwin' or sys_platform == 'linux'" },
     { name = "djangorestframework-stubs", extra = ["compatible-mypy"], marker = "sys_platform == 'darwin' or sys_platform == 'linux'" },
     { name = "lxml-stubs", marker = "sys_platform == 'darwin' or sys_platform == 'linux'" },
+    { name = "microsoft-python-type-stubs", marker = "sys_platform == 'darwin' or sys_platform == 'linux'" },
     { name = "mypy", marker = "sys_platform == 'darwin' or sys_platform == 'linux'" },
+    { name = "mypy-baseline", marker = "sys_platform == 'darwin' or sys_platform == 'linux'" },
     { name = "types-bleach", marker = "sys_platform == 'darwin' or sys_platform == 'linux'" },
     { name = "types-colorama", marker = "sys_platform == 'darwin' or sys_platform == 'linux'" },
     { name = "types-dateparser", marker = "sys_platform == 'darwin' or sys_platform == 'linux'" },
@@ -3433,7 +3449,9 @@ typing = [
     { name = "django-stubs", extras = ["compatible-mypy"] },
     { name = "djangorestframework-stubs", extras = ["compatible-mypy"] },
     { name = "lxml-stubs" },
+    { name = "microsoft-python-type-stubs", git = "https://github.com/microsoft/python-type-stubs.git" },
     { name = "mypy" },
+    { name = "mypy-baseline" },
     { name = "types-bleach" },
     { name = "types-colorama" },
     { name = "types-dateparser" },