feat: add fasthtml demo-app

.github/workflows/link-checker.yml

@@ -30,6 +30,7 @@ jobs:
       ignore-urls: |-
         src/main/application/schemas/wiki.sd#L80
         /localhost:8080/
+        /localhost:5001/
         src/main/application/search/query-profiles
         /hub.docker.com/r/vespaengine/vespa/tags/
       swap-urls: |-

examples/fasthtml-demo/.env.example

@@ -0,0 +1,8 @@
+# The URL of your Vespa Cloud application (you get it when running `deploy_app.ipynb`)
+VESPA_APP_URL=https://my-vespa-endpoint.z.vespa-app.cloud/
+# The secret token for your Vespa Cloud application (Created in Vespa Cloud Console)
+VESPA_CLOUD_SECRET_TOKEN=vespa_cloud_mysecret_tokenabcdeabcdeabcdedcba 
+# Username of admin user (has access to query logs in SQLite DB)
+ADMIN_NAME=admin
+# Password of admin user 
+ADMIN_PWD=admin 

examples/fasthtml-demo/.gitignore

@@ -0,0 +1,15 @@
+ft/
+db/
+session/
+todo/
+fasthtml/
+.venv/
+__pycache__/
+.python-version
+# Python stuff
+*.pyc
+*.pyo
+
+
+.env
+.sesskey

examples/fasthtml-demo/Dockerfile

@@ -0,0 +1,10 @@
+FROM python:3.10
+WORKDIR /code
+COPY --link --chown=1000 . .
+RUN mkdir -p /tmp/cache/ session/ db/
+RUN chmod a+rwx -R /tmp/cache/ session/ db/
+ENV HF_HUB_CACHE=HF_HOME
+RUN pip install --no-cache-dir -r requirements.txt
+
+ENV PYTHONUNBUFFERED=1 PORT=7860
+CMD ["python", "main.py"]

examples/fasthtml-demo/Dockerfile.nonhf

@@ -0,0 +1,16 @@
+FROM python:3.10
+# Set working directory
+WORKDIR /code
+# Copy only the requirements file to leverage Docker cache
+COPY --chown=1000 requirements.txt .
+# Install dependencies
+RUN pip install --no-cache-dir -r requirements.txt
+# Copy the rest of the application code
+COPY --chown=1000 . .
+# Create necessary directories with appropriate permissions
+RUN mkdir -p /tmp/cache/ session/ \
+    && chmod a+rwx -R /tmp/cache/ session/
+# Set environment variable
+ENV PYTHONUNBUFFERED=1
+# Define the command to run the application
+CMD ["python", "main.py"]

examples/fasthtml-demo/README.md

@@ -0,0 +1,141 @@
+---
+title: vespa-engine/fasthtml-vespa
+emoji: 🚀
+colorFrom: purple
+colorTo: red
+sdk: docker
+app_file: main.py
+pinned: false
+termination_grace_period: 2m
+---
+<!-- Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root. -->
+
+<picture>
+  <source media="(prefers-color-scheme: dark)" srcset="https://assets.vespa.ai/logos/Vespa-logo-green-RGB.svg">
+  <source media="(prefers-color-scheme: light)" srcset="https://assets.vespa.ai/logos/Vespa-logo-dark-RGB.svg">
+  <img alt="#Vespa" width="200" src="https://assets.vespa.ai/logos/Vespa-logo-dark-RGB.svg" style="margin-bottom: 25px;">
+</picture>
+
+
+# FastHTML Vespa frontend
+
+This is a simple frontend for Vespa search engine. It is built using [FastHTML](https://www.fastht.ml/) and written in pure Python.
+
+Search page             |  Login page         |  Query logs
+:-------------------------:|:-------------------------:|:-------------------------:
+![search](assets/search-page.png)  |  ![admin-login](assets/admin-login.png) |  ![query-log](assets/query-log.png)
+
+### Features
+
+- Simple search interface, with links to search results.
+- Accordion with full JSON-response from Vespa.
+- SQLite DB for storing queries.
+- Admin authentication for viewing and downloading queries.
+- Deployment options - Docker + [Huggingface spaces](https://huggingface.co/spaces/).
+
+### Why?
+
+We have recognized the need, both for ourselves and others, to be able to set up a simple frontend for Vespa, without having to navigate the frontend framework jungle. Demo frontend apps often end up with a bunch of dependendcies and angry github renovate bots. :robot: :sad:
+
+This sample-app can serve as an example of how you can build and deploy a simple frontend for Vespa, using FastHTML.
+
+### How to use
+
+#### 1. Clone this folder to your local machine 📂
+
+The command below will clone the repository and only fetch the `fasthtml-demo` directory.
+
+```bash
+git clone --depth 1 --filter=blob:none --sparse https://github.com/vespa-engine/sample-apps.git temp-sample-apps && cd temp-sample-apps && git sparse-checkout set fasthtml-demo && mkdir -p ../fasthtml-demo && mv fasthtml-demo/* ../fasthtml-demp/ && cd .. && rm -rf temp-sample-apps
+```
+
+#### 2. Install dependencies 🔧
+
+```bash
+pip install -r requirements.txt
+```
+
+#### 3. Run the app locally  💻
+
+```bash
+python main.py
+```
+
+At this point, you should be able to access the app at [http://localhost:5001](http://localhost:5001).
+
+But, you will _not_ be able to search for anything, as your environment variables are not set up.
+
+#### 4. Deploy and feed your Vespa application ▶️
+
+By running the `deploy_app.ipynb` notebook, you will deploy a Vespa application to the Vespa Cloud. The application is just a sample hybrid search application using the [BEIR/nfcorpus](https://huggingface.co/datasets/BeIR/nfcorpus) dataset.
+Feel free to replace the dataset and application with your own.
+
+Make sure to replace these variables at the top of the notebook with your own values:
+
+```python
+# Replace with your tenant name from the Vespa Cloud Console
+tenant_name = "mytenant"
+# Replace with your application name (does not need to exist yet)
+application = "fasthtml"
+# Token id (from Vespa Cloud Console)
+token_id = "fasthtmltoken"
+```
+
+#### 5. Set up environment variables 🔐
+
+Make sure to add the output of the `token_endpoint` from the `deploy_app.ipynb`- notebook to your `.env.example` file.
+This value should be placed in the `VESPA_APP_URL` environment variable.
+
+At the same time, you should rename the `.env.example` file to `.env`. This is added to the `.gitignore` file.
+
+#### 6. Run the app locally 🚀
+
+Now, you should be able to run the app locally and search for queries. 
+
+```bash
+python main.py
+```
+
+Open your browser and navigate to [http://localhost:5001](http://localhost:5001).
+
+### Deployment
+
+If you want to deploy the app, you set the `DEV_MODE=False` in `main.py`.
+This will disable loading of environment variables from the `.env` file, and instead use the environment variables set in the deployment environment.
+
+#### Docker 🐳
+
+You can build and run the app using Docker.
+
+Note that there are two Dockerfiles in the repo:
+
+- `Dockerfile` is for building the image for Huggingface Spaces.
+- `Dockerfile.nonhf` is for building an image that can be run locally or on any other platform.
+
+Build the image:
+
+```bash
+docker build -t fhtdemoimg . -f Dockerfile.nonhf 
+```
+
+**Run the container:**
+
+- Makes the environment variables in the `.env` file available to the container.
+- Will mount the `db/` folder to the container, so that the SQLite database is persisted between runs.
+- Sets the hostname to `dockerhost`, so that we can know use that to enable hot-reloading in the FastHTML app.
+- Maps the default Starlette port `5001` to `8000` on the host.
+
+```bash
+docker run --name fhtdemo --rm --env-file .env -p 8000:5001 -h dockerhost -v $(pwd)/db:/code/db fhtdemoimg
+```
+
+#### Huggingface 🤗 Spaces
+
+This deployment option is free. The deployment script is shamelessly copied from the [fasthtml-hf](https://github.com/AnswerDotAI/fasthtml-hf) repo. Check it out for details on cli-options, configuration and DB-backup options.
+
+1. Get a huggingface token with `write` permissions. You can do this by going to your [Huggingface profile](https://huggingface.co/settings/tokens) and create a new token.
+2. Set the `HF_TOKEN` environment variable to the token you just created.
+3. Run `python deploy_hf.py <your-space-name> [--private true]` to deploy the app to Huggingface Spaces.
+4. Remember to add `VESPA_APP_URL` and `VESPA_CLOUD_SECRET_TOKEN` to the environment variables in the [Huggingface Spaces settings.](https://huggingface.co/docs/hub/en/spaces-overview#managing-secrets)
+
+### Go build some cool Vespa apps! 🚀

examples/fasthtml-demo/config.ini

@@ -0,0 +1,5 @@
+[DEFAULT]
+dataset_id = space-backup
+db_dir = data
+private_backup = True
+interval = 5