API

API

A rudimentary REST API is available for configuring and getting data from Hoplite. The default config listens on all IPs at port 5000, but a specific listener IP and port can be specified using the --api parameter when starting Hoplite.

The following examples assume that curl is running on the same host as the Hoplite server.

Get all configs and data

pi@hoplite:~ $ curl -X GET -s http://127.0.0.1:5000/v1/ | jq
{
  "code": 200,
  "data": {
    "v1": {
      "display": "st7735",
      "hx_list": [
        {
          "channels": {
            "A": {
              "co2": false,
              "name": "American Wheat",
              "offset": 297569.1111111111,
              "refunit": 21.189888888888877,
              "size": "corny",
              "tare": 4,
              "volume": 18.9,
              "weight": 4610
            }
          },
          "dout": 5,
          "pd_sck": 6
        },
        {
          "channels": {
            "A": {
              "co2": true,
              "name": "CO2",
              "offset": 128814.44444444444,
              "refunit": 21.39255555555556,
              "size": "custom",
              "tare": 4.82,
              "volume": 2.27,
              "weight": 5921
            }
          },
          "dout": 12,
          "pd_sck": 13
        }
      ],
      "temp": 0,
      "weight_mode": "as_kg_net"
    }
  },
  "message": null,
  "status": "ok"
}

Get a specific HX711 sensor

curl -X GET -v -s http://127.0.0.1:5000/v1/hx/<index>/

where <index> is the index of the sensor you want to get. The previous command lists the sensors in order, so you can either count the entries from that command, or just spam curl and increment the index until you get the entry you're after.

Get a specific HX711 sensor channel

curl -X GET -v -s http://127.0.0.1:5000/v1/hx/<index>/<channel>/

where <index> is as described above, and <channel> is either A or B. The HX711 module supports two channels for attached load cells.

Get a specific attribute of an HX711 sensor channel

curl -X GET -v -s http://127.0.0.1:5000/v1/hx/<index>/<channel>/<attribute>/

where <index> and <channel> are as described above, and <attribute> is one of the attributes of the channel.

Set a specific attribute of an HX711 sensor channel

pi@hoplite:~ $ curl -X PUT -H "Content-Type: application/json" -d '{"name": "Bud Light"}' -s http://127.0.0.1:5000/v1/hx/0/A/name
{
  "code": 200, 
  "data": {
    "name": "Bud Light"
  }, 
  "message": "name successfully updated", 
  "status": "ok"
}

Useful for updating names, keg sizes, etc. though that can be done via the web interface as well.

Add a new HX711

pi@hoplite:~ $ curl -X POST -H "Content-Type: application/json" -d '{"pd_sck": 27, "dout": 17, "channels": { "A": {"name": "Yuengling", "size": "custom", "tare": 9.7, "volume": 29.3} } }' -s http://127.0.0.1:5000/v1/hx/
{
  "code": 200, 
  "data": {
    "0": {
      "channels": {
        "A": {
          "co2": false, 
          "name": "Yuengling", 
          "offset": 0, 
          "refunit": 0, 
          "size": "custom", 
          "tare": 9.7, 
          "volume": 29.3
        }
      }, 
      "dout": 17, 
      "pd_sck": 27
    }
  }, 
  "message": "Index 0 successfully created or updated", 
  "status": "ok"
}

This is how you get started, by adding your first HX711 and one or both channels. The message field of the response will contain the index that you just created, as well as the data field.

Add a channel to an existing HX711

pi@hoplite:~ $ curl -X POST -H "Content-Type: application/json" -d '{"name": "Yuengling", "size": "custom", "tare": 9.7, "volume": 29.3}' -s http://127.0.0.1:5000/v1/hx/0/B
{
  "code": 200, 
  "data": {
    "B": {
      "co2": false, 
      "name": "Yuengling", 
      "offset": 0, 
      "refunit": 0, 
      "size": "custom", 
      "tare": 9.7, 
      "volume": 29.3
    }
  }, 
  "message": "B successfully created or updated", 
  "status": "ok"
}

Similar to above, except you need to specify the index and channel you are targeting.

Delete an existing HX711

pi@hoplite:~ $ curl -X DELETE -s http://127.0.0.1:5000/v1/hx/0/
{
  "code": 200, 
  "data": {
    "0": {
      "channels": {
        "A": {
          "co2": false, 
          "name": "Yuengling", 
          "offset": 0, 
          "refunit": 0, 
          "size": "custom", 
          "tare": 9.7, 
          "volume": 29.3
        }, 
        "B": {
          "co2": false, 
          "name": "Yuengling", 
          "offset": 0, 
          "refunit": 0, 
          "size": "custom", 
          "tare": 9.7, 
          "volume": 29.3
        }
      }, 
      "dout": 17, 
      "pd_sck": 27
    }
  }, 
  "message": "0 successfully deleted", 
  "status": "ok"
}

The DELETE action will return the deleted data, just in case you got the wrong index and need to re-add it.

Delete an existing channel from an HX711

pi@hoplite:~ $ curl -X DELETE -s http://127.0.0.1:5000/v1/hx/0/B/
{
  "code": 200, 
  "data": {
    "B": {
      "co2": false, 
      "name": "Yuengling", 
      "offset": 0, 
      "refunit": 0, 
      "size": "custom", 
      "tare": 9.7, 
      "volume": 29.3
    }
  }, 
  "message": "B successfully deleted", 
  "status": "ok"
}

The DELETE action will return the deleted data, just in case you got the wrong index or channel and need to re-add it.