fixes typo and shortens text

## vlkb-siav2

is a web-application to discover astronomical data (supports FITS-files) and described in a [VO ObsTAP table](https://ivoa.net/documents/ObsCore).

is a web-application to discover astronomical data (FITS-files) and described in a [VO ObsTAP table](https://ivoa.net/documents/ObsCore).

It implements IVOA recommendation [SIA version 2](https://ivoa.net/documents/SIA) with optional VLKB-specific features:

- provides overlap code

The service consists of **vlkb-siav2** web-application and associated **vlkb-obscore** command line tool to create the ObsTAP table from FITS-files headers.

The service may be launched by docker compose with [compose.yaml](./docker/example-compose.yaml). The database service is not needed, running database instance may de set directly by DB_URI parameters. Additionaly choose context root and point to the data access service.

To check the service status access the availability endpoint:

The service may be launched by docker compose with [compose.yaml](./docker/example-compose.yaml). The local database service is optional. Instead remote database instance may de set in DB_URI parameter. For service status check, access the availability endpoint:

```bash

curl --get http://localhost:8004/vlkb/datasets/availability

```

## Endpoints

## End-points

- **availability** is a [VOSI](https://ivoa.net/documents/VOSI/20170524/REC-VOSI-1.1.html) end-point and returns information whether the service is active

- **capabilities** is a [VOSI](https://ivoa.net/documents/VOSI/20170524/REC-VOSI-1.1.html) end-point which describes service' functions and paramters

## Docker image

The vlkb-siav2 is available from the gitlab repositary of this project. 

The vlkb-siav2 is available from the gitlab repository of this project. 

Configuration parameters are set by these docker environment variables:

| parameter | description  |

|---------|--------------|

| **DISCOVERY_CONTEXT_ROOT** | root of the vlkb-soda end-points |

| **DISCOVERY_CONTEXT_ROOT** | root of the end-points |

| **DB_URI** | DB which holds ObsTAP table |

| **DB_USERNAME** | DB user which has access to ObsTAP |

| **DB_PASSWORD** | and user's password |