iotdb-thing

IOTDB Module for Managing Things

Introduction

This is a total / radical rewriting of our Thing manipulation library. It has no knowledge of Things, per se - it's meant to plug into our other modules such iotdb and iotql.

The goals are:

• write around "band" concept
• use ES6 javascript
• use composition rather than classes
• promises where appropriate
• maximal orthogonality in code and interfaces
• test driven development
• 100% code coverage in tests

Examples

For the most part, Thing objects will be created for you and you just manipulate them as per below.

General Use

There are much deeper ways of using these objects, but these are the most common you'll want to use

Creation

const thing = require("iotdb-thing").thing;
const thing_1 = thing.make()
const thing_2 = thing.make({
    "model": …,
    "meta": …,
    "istate": …,
    "ostate": …,
    "connection": …,
});

Getting Values

thing_1.get(":temperature");
thing_1.get(":temperature", thing.as.fahrenheit());

Setting Values

thing_1.set(":on", true);
thing_1.set(":temperature", 20, thing.as.fahrenheit());

Bands

ostate

The ostate is used to manipulate a thing - it's the output state.

get the ostate

const ostate_1 = thing_1.band("ostate");

see the current values

const d = ostate_1.state();

set a value semantically

const promise = ostate_1.set(":on", true);

set a value non-semantically

const promise = ostate_1.set("power", true);

change a whole bunch of values (non-semantic). Note that update is always non-semantic, it's dealing the raw underlying data.

const promise = ostate_1.update({
    "power": true,
    "level": 50,
})

istate

The istate is used to current the current readings from a thing - it's the input state.

Get the istate object

const istate_1 = thing_1.band("istate");

See the current values

const d = istate_1.state();

Get a particular value semantically. first and list guarentee a non-array or an array respectively, get just returns what is there

const is_on_get = istate_1.get(":on")
const is_on_first = istate_1.first(":on")
const is_on_list = istate_1.list(":on")

Get a particular value non-semantically

const is_on_get = istate_1.get("powered")
const is_on_first = istate_1.first("powered")
const is_on_list = istate_1.list("powered")

Listen for a change semantically

istate_1.on(":on", function(_thing, _band, _new_value) {
});

Listen for a change non-semantically

istate_1.on("powered", function(_thing, _band, _new_value) {
});

Paramaterized Data

Because we have a strong idea of data types, you can parameterize values being passed into things; and you can coerce output values.

Helper functions parametization

ostate_1.set("level", 50, thing.as.percent());
ostate_1.set("level", .5, thing.as.unit());
ostate_1.set("temperature", 22, thing.as.celsius());

Coercing output value

istate_1.get("temperature", thing.as.celsius());

Getting type definitions

This will return a semantic description describing this particular attribute of the Thing.

thing_1.attribute("temperature")

or with a coercion

thing_1.attribute("temperature", thing.as.celsius());