Getting Started

DeNS Query is implemented with the dens-query-cli executable. In the git repository, it is provided at the flake output packages.<system>.dens-query-cli, so Nix users can enter a shell with the dens-query-cli executable with the following command.

nix shell github:mlabs-haskell/DeNS#dens-query-cli

When dens-query-cli is executed, it will require that the following dependencies are running:

Moreover, it will look for a configuration file (see Configuration file format) provided in the environment variable in DENS_QUERY_CONFIG for the relevant dependency connection information along DeNS specific information. Thus, executing dens-query-cli from a shell will often look as follows.

DENS_QUERY_CONFIG=./path/to/config.json dens-query-cli

Configuration file format

Users can choose between making dens-query-cli serve HTTP requests on the UNIX domain (via Unix domain sockets) or the Internet domain.

dens-query-cli serving HTTP requests on the UNIX domain

Example configuration file for running dens-query-cli on the UNIX domain
{
  "ogmios": (1)
    {
      "url": "ws://127.0.0.1:1337"
    },
  "database": (2)
    {
      "user": "dens",
      "password": "",
      "socket": {
        "name": "UnixDomain",
        "fields": [
          {
            "path": "/var/postgres/"
          }
        ]
      },
      "database": "dens"
    },
  "server": (3)
    {
      "name": "UnixDomain",
      "fields": [
        {
          "path": "/ipc/.s.dens-query"
        }
      ],
    },
  "protocolNft": (4)
    {
       "currency_symbol": "0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F",
       "token_name": ""
    }
}

  1. The connection to Ogmios.

  2. The connection to a PostgreSQL database.

  3. The Unix domain socket that dens-query-cli will serve HTTP requests on.

  4. The protocol’s NFT to uniquely identify the DeNS protocol used. The currency_symbol and token_name are hex encoded.

dens-query-cli serving HTTP requests on the Internet domain

Example configuration file for running dens-query-cli on the Internet domain
{
  "ogmios":
    {
      "url": "ws://127.0.0.1:1337"
    },
  "database":
    {
      "database": "dens",
      "password": "",
      "socket": {
        "name": "UnixDomain",
        "fields": [
          {
            "path": "/var/postgres/"
          }
        ]
      },
      "user": "dens"
    },
  "server": (1)
    {
      "name": "InternetDomain",
      "fields": [
        {
          "host": "127.0.0.1",
          "port": "6969",
        }
      ],
    },
  "protocolNft":
    {
       "currency_symbol": "0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F",
       "token_name": ""
    }
}

  1. The host and port that dens-query-cli will serve HTTP requests on.