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README.md

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+# tailscalesd
+
+> Service discovery for tailscale
+
+Returns a list of services for Prometheus to scrape, with some extra smarts for Guardian Project Ops.
+
+See [the prometheus docs][0] for more information on the HTTP service discovery format.
+
+[0]: https://prometheus.io/docs/prometheus/latest/http_sd/
+
+## Usage
+
+### Configuration
+
+Configuration values can be set using environment variables, or optionally loaded from an environment file. The settings include:
+
+- **host** (`TAILSCALESD_HOST`): The host address on which the application will bind (designed to be used in a container, BE CAREFUL!). Default is `0.0.0.0`.
+- **port** (`TAILSCALESD_PORT`): The port number on which the application will be accessible. Default is `9242`.
+- **interval** (`TAILSCALESD_INTERVAL`): The interval on which the Tailscale API is polled in seconds. Default is `60`.
+- **tailnet** (`TAILSCALESD_TAILNET`): The Tailscale tailnet identifier (required).
+- **api_key** (`TAILSCALESD_API_KEY`): The Tailscale API key (required).
+
+#### Environment File
+
+You can also specify an environment file to load configuration values. The path to the environment file should be set in the `TAILSCALESD_ENV_FILE` environment variable. All of the config values can be provided in the env file.
+
+**Example Environment File** (`env`):
+
+```env
+TAILSCALESD_TAILNET=my-tailnet
+TAILSCALESD_API_KEY=my-api-key
+TAILSCALESD_HOST=127.0.0.1
+```
+
+### Running the Application
+
+1. **Install Dependencies**: Ensure that all required dependencies are installed.
+
+    ```sh
+    poetry install
+    ```
+
+2. **Set Configuration**: Set the necessary environment variables or create an environment file with the configuration values.
+
+3. **Start the Application**: Run the application using the following command:
+
+    ```sh
+    poetry run tailscalesd
+    ```
+
+4. **Access the Application**: The application will be accessible at `http://<host>:<port>`.
+