Webthing-arduino ThingProperty Unit

WebThings
#1

Hi,

I’m wondering if there is a way to set a ThingProperty Unit when using the MultiLevelSensor capabilty with the LevelProperty.

This is how I have it setup right now and I’m able to get my value as a Number but without a Unit.

const char* sensorTypes[] = {"MultiLevelSensor", nullptr};
ThingDevice soilMoistureSensor("soilMoistureSensor", "Analog Soil Moisture Sensor", sensorTypes);
ThingProperty moistureLevel("moistureLevel", "Percent of moisture in the soil", NUMBER, "LevelProperty");

LevelProperty mentions an optional Unit but I’m not sure how to set it using webthing-arduino.

#2

You should be able to do this:

moistureLevel.unit = "percent";
#3

I tried adding that line directly below the existing code

const char* sensorTypes[] = {"MultiLevelSensor", nullptr};
ThingDevice soilMoistureSensor("soilMoistureSensor", "Analog Soil Moisture Sensor", sensorTypes);
ThingProperty moistureLevel("moistureLevel", "Percent of moisture in the soil", NUMBER, "LevelProperty");
moistureLevel.unit = "percent";

The Arduino IDE says

'moistureLevel' does not name a type
#4

What version of webthing-arduino are you using? Are you using the published v0.4.1 version, or the latest in GitHub?

#5

That line should be placed in the setup function, not the top level

#6

I’m using v0.4.1 installed through the Library manager in the Arduino IDE

#7

I moved the line to the setup function

const char* sensorTypes[] = {"MultiLevelSensor", nullptr};
ThingDevice soilMoistureSensor("soilMoistureSensor", "Analog Soil Moisture Sensor", sensorTypes);
ThingProperty moistureLevel("moistureLevel", "Percent of moisture in the soil", NUMBER, "LevelProperty");


void setup() {
  moistureLevel.unit = "percent";

I’m now getting a new error but seem to be getting closer

'class ThingProperty' has no member named 'unit'
#8

You’ll need to switch to a newer version of the webthing-arduino library, from GitHub.

I’m sure @hobinjk can provide assistance with that, if needed.

#9

Yes, I should have just updated the version of the library available in the Arduino IDE library manager but while that’s propagating outwards you can also download the zip from https://github.com/mozilla-iot/webthing-arduino/releases/download/v0.9.0/webthing-arduino.zip

#10

Many thanks! Cloned the git repo and the error is gone, flashing now :slight_smile:

Confirmed, is working. I also managed to add readOnly and it works as intended :slight_smile:

Screenshot%20from%202019-08-15%2021-41-55
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#11

I noticed that these were not working

moistureLevel.title = "Moisture";
moistureLevel.minimum = 0;
moistureLevel.maximum = 100;

So I tried adding them to Thing.h and ESPWebThingAdapter.h in the same way that unit and readOnly are added and it seems to work!

Thing.h

class ThingItem {
public:
  String id;
  String description;
  ThingPropertyType type;
  String atType;
  ThingItem* next = nullptr;

  bool readOnly = false;
  String unit = "";
  // this is what I added
  String title = "";
  double minimum;
  double maximum;

ESPWebThingAdapter.h

      if (item->readOnly) {
        prop["readOnly"] = true;
      }

      if (item->unit != "") {
        prop["unit"] = item->unit;
      }
      // this is what I added
      if (item->title != "") {
        prop["title"] = item->title;
      }

      if (item->minimum < item->maximum) {
        prop["minimum"] = item->minimum;
      }

      if (item->maximum > item->minimum) {
        prop["maximum"] = item->maximum;
      }
#12

Would you want to open a PR with those changes?

#13

Absolutely! I haven’t done it before but I read through this: https://help.github.com/en/articles/creating-a-pull-request

Which suggests that I need write access to create a branch

Anyone with read permissions to a repository can create a pull request, but you must have write permissions to create a branch.

I did so and tried to push the changes but I got this error:

remote: Permission to mozilla-iot/webthing-arduino.git denied to lundsholm.
fatal: unable to access 'https://github.com/mozilla-iot/webthing-arduino.git/': The requested URL returned error: 403

EDIT: @mstegeman Let me know if I should contact you any other way to keep this thread clean and on topic :stuck_out_tongue:

#14

You’ll actually want to fork the repo first, then create a branch and submit a PR from that. Here’s a nice tutorial: https://gist.github.com/Chaser324/ce0505fbed06b947d962

#15

Thank you! PR is submitted :nerd_face: