A web UI for groupdocs-viewer-net — view 170+ document and image formats in a browser. Mount inside an existing FastAPI / Flask / Django app, or run standalone via the bundled CLI.
The frontend is the same battle-tested Angular SPA from the GroupDocs.Viewer for .NET UI project, vendored into this package — one pip install and you're done.
pip install groupdocs-viewer-net-uiOptional cloud-storage / cache backends:
pip install "groupdocs-viewer-net-ui[s3]" # S3FileStorage
pip install "groupdocs-viewer-net-ui[azure]" # AzureBlobFileStorage
pip install "groupdocs-viewer-net-ui[redis]" # RedisCache
pip install "groupdocs-viewer-net-ui[all]"groupdocs-viewer-ui serve --files ./documents --cache ./.viewer-cache
# → http://127.0.0.1:8080/viewer/docker compose up
# Drop documents into ./documents on the hostfrom groupdocs_viewer_ui import Config, create_app
from groupdocs_viewer_ui.cache.local import LocalFileCache
from groupdocs_viewer_ui.storage.local import LocalFileStorage
from groupdocs_viewer_ui.viewer.selfhost import SelfHostViewer
storage = LocalFileStorage("./Files")
app = create_app(
Config(),
storage=storage,
cache=LocalFileCache("./Cache"),
viewer=SelfHostViewer(storage=storage),
)
# Run with: uvicorn myapp:appcreate_app() returns a Starlette ASGI app — mount it under FastAPI directly, or bridge to Flask/Django with a2wsgi. See examples/ for runnable patterns.
Config() accepts knobs for rendering mode, preload count, initial zoom, UI toggles (header, toolbar, thumbnails, search, print, etc.), localization, branding, and routing. See AGENTS.md for the full field reference.
Config(
rendering_mode="html", # or "image"
preload_pages=3,
initial_zoom="Fit Page", # or "Fit Width", "Fit Height", "100%", "75%", etc.
enable_thumbnails=True,
ui_title="My Document Viewer",
custom_css="<style>:root { --c-bg-brand: #0d9488; }</style>",
)Built-in: LocalFileStorage, S3FileStorage ([s3] extra), AzureBlobFileStorage ([azure] extra). Implement the FileStorage protocol for anything else — three async methods. See examples/05_custom_storage/ for a SQLite-backed example.
Built-in: InMemoryCache, LocalFileCache, RedisCache ([redis] extra). When you supply both viewer and cache to create_app(), the viewer is auto-wrapped in a CachingViewer decorator — no manual composition required. Implement the FileCache protocol for custom backends. See examples/06_custom_cache/ for a TTL wrapper.
from starlette.exceptions import HTTPException
async def require_session(request):
if request.cookies.get("session") not in VALID_SESSIONS:
raise HTTPException(status_code=401, detail="Login required")
app = create_app(..., auth_check=require_session)The check runs before every /viewer-api/* request. /health, the SPA, and static assets are deliberately not guarded — wrap the whole app yourself if you need broader scope. See examples/07_auth/ for session-cookie + bearer-token patterns.
For rate limiting, pair with slowapi or asgi-ratelimit as standard Starlette middleware.
| Path | Shows |
|---|---|
examples/01_cli_quickstart/ |
Zero-config CLI demo |
examples/02_fastapi_basic/ |
Mount in FastAPI |
examples/03_flask_basic/ |
Mount in Flask via a2wsgi |
examples/04_custom_branding/ |
Custom logo + CSS |
examples/05_custom_storage/ |
SQLite FileStorage |
examples/06_custom_cache/ |
TTL FileCache decorator |
examples/07_auth/ |
Session cookie + bearer token auth |
groupdocs-viewer-net needs libgdiplus, libfontconfig1, fonts-liberation, and fonts-dejavu for rendering. The bundled Dockerfile installs them; for bare metal:
sudo apt-get install -y libgdiplus libfontconfig1 fontconfig fonts-liberation fonts-dejavuAGENTS.md— full reference: config fields, protocols, extensibility, gotchasexamples/— runnable end-to-end demos for each integration pattern- GroupDocs.Viewer for Python via .NET docs
pip install -e ".[dev]"
pytest # 107 passing (~21s; 5 e2e tests render a real DOCX)
ruff check src tests
mypy srcMIT — see LICENSE.