Re: [generic-sensor] - Sensors API - core

Hi Felipe,

Thank you for feedback, the issue that you and Marcos have raised can be
split into two problems:

1) Namespacing
It provides some benefits, yet it may break discovery API, as there can be
multiple sensors of the same type. Please take a look at
https://github.com/w3c/sensors/issues/127 and see rationale for dropping
namespaces for now.

2) Discovery
Tobie made an issue (https://github.com/w3c/sensors/issues/7) that should
cover sensor discovery use-cases. With discovery API, developers would be
able to call something like "Promise<Sensor[]> Sensor.enumerate(SensorType
type?);" to get list of supported sensors then, you can write your darkRoom
sensor in a following way:

function createDarkRoomSensor() {
  Promise.all([
    Sensor.enumerate("light"),
    Sensor.enumerate("proximity")
  ]).then(function([lightSensors, proximitySensors]){
     // select what sensors to use or [0] to get first one
     // create fusion from proximity and ambient light
     let myDarkRoomSensor = …;
     return myDarkRoomSensor;
  });
});

// If you like namespaces.
navigator.sensors = {
  darkRoom: createDarkRoomSensor,
  light: () => { return Sensor.enumerate("light").then(lights =>
lights[0]); }
}

Kind regards,
Alexander Shalamov

On Fri, Nov 25, 2016 at 3:48 PM, Felipe Nascimento de Moura <
felipenmoura@gmail.com> wrote:

> Hi.
>
> Reading this e-mail: http://lists.w3.org/Archives/Public/public-device-
> apis/2016Nov/0024.html
> I could add now, yet a new different pattern to the list I showed in the
> first e-mail:
>
> ```
> let sensor = new Magnetometer(); // new instance of a global Constructor
> sensor.start();
>
> sensor.onchange = function(event) { ... };
> ```
>
> I think this is the moment for us to think about a `core` for sensors,
> like `navigator.sensors....` :)
>
>
> On Thu, Nov 24, 2016 at 1:06 PM, Felipe Nascimento de Moura <
> felipenmoura@gmail.com> wrote:
>
>> > https://github.com/w3c/sensors  ... some are already supported in
>> Chrome ;)
>>
>> nice, I have already done some tests with the currently supported ones,
>> but even though, I think an aggregator for all the sensors is very
>> important. Even for hacking and discoverability.
>>
>> navigator.sensors.tirePressure().then( ... )
>>
>> Actually, navigator.sensors could even have a "getter" for any method
>> that does not exist to return a rejected promise, instead of a "undefined
>> is not a function" error.
>> This way, calling `navigator.sensors.anInexistin
>> gSensor().then(...).catch(...)` would reject until the sensors was
>> created or supported.
>>
>> Thinking it further, we could even have a `navigator.sensors.create` with
>> a pattern for developers to create their own sensors based in other
>> information...let's say:
>>
>> ```
>> navigator.sensors.create("darkRoom", function(mySensor){
>>   Promise.all([
>>     navigator.sensors.light(),
>>     navigator.sensors.proximity()
>>   ]).then(function([lightSensor, proximitySensor]){
>>     // combine lightSensor and proximity to identify when the room is dark
>>     // and the device is not inside a pocket, for example
>>     // you can dispatch events here on mySensor
>>   });
>> });
>>
>> // then, afterwards
>>
>> navigator.sensors.darkRoom().then(darkRoomSensor=>{
>>   darkRoomSensor.addEventListener(...);
>> });
>> ```
>>
>> Did I go too far? :p
>>
>>
>> On Thu, Nov 24, 2016 at 3:04 AM, Marcos Caceres <marcos@marcosc.com>
>> wrote:
>>
>>> On November 24, 2016 at 3:41:07 PM, Felipe Nascimento de Moura
>>> (felipenmoura@gmail.com) wrote:
>>> > I think I should be able to type "navigator.sensors" in my console and
>>> see
>>> > even an autocomplete with the possibilities.
>>>
>>> https://github.com/w3c/sensors  ... some are already supported in
>>> Chrome ;)
>>>
>>
>>
>>
>> --
>> [ ]s
>>
>> *--*
>>
>> *Felipe N. Moura*
>> Web Developer, Google Developer Expert
>> <https://developers.google.com/experts/people/felipe-moura>, Founder of
>> BrazilJS <https://braziljs.org/> and Nasc <http://nasc.io/>.
>>
>> Website:  http://felipenmoura.com / http://nasc.io/
>> Twitter:    @felipenmoura <http://twitter.com/felipenmoura>
>> Facebook: http://fb.com/felipenmoura
>> LinkedIn: http://goo.gl/qGmq
>> ---------------------------------
>> *Changing  the  world*  is the least I expect from  myself!
>>
>
>
>
> --
> [ ]s
>
> *--*
>
> *Felipe N. Moura*
> Web Developer, Google Developer Expert
> <https://developers.google.com/experts/people/felipe-moura>, Founder of
> BrazilJS <https://braziljs.org/> and Nasc <http://nasc.io/>.
>
> Website:  http://felipenmoura.com / http://nasc.io/
> Twitter:    @felipenmoura <http://twitter.com/felipenmoura>
> Facebook: http://fb.com/felipenmoura
> LinkedIn: http://goo.gl/qGmq
> ---------------------------------
> *Changing  the  world*  is the least I expect from  myself!
>