[SOLVED] Quering Enginio with QML

[guidupas]

Hello all!

I need to query data from enginio databse and use it in a ComboBox, but I could not figure out how to do it. Could someone help me?

Thanks

[SGaist]

Hi,

Did you took a look at getting started Enginio QML ?

[clochydd]

Hi guidupas,

here's a small snippet showing how to query enginio by using EnginioModel:

EnginioClient {
	id: client
	backendId: "myID..."
}


EnginioModel {
	id: enMod
	client: client
	query: 
		{
		"objectType" : "objects.myobject",
		"sort": [{"sortBy":"updatedAt","direction":"desc"}],
		"query": {"updatedAt": {"$gt": {"$type": "time","$value": getYesterday()}}},
		"limit": 15
		}
}


function getYesterday( ) {
	var today = new Date();
	today.setDate(today.getDate()-5)
	return Qt.formatDate(today, "yyyy-MM-ddT00:00:00Z");
}

You may use all the objects in the EnginioModel enMod in your script:

text: updatedAt 

etc.

Hope, it helps

[guidupas]

@SGaist

Hello!

Thanks for the reply

Yes, I have seem the link you suggested, but it just show how to insert data and my difficult here is how to get and use the data from Enginio.

[guidupas]

@clochydd

Hello!

Thanks for the reply!

The code you posted helped a lot, but I could not, yet, use the data. When I try to use it like you suggested: text: updatedAt it shows me the message:

qrc:/main.qml:117: ReferenceError: updatedAt is not defined

Here is my code. I will became grateful if you could help me:

EnginioClient {
        id: clienteEnginio
        backendId: "MyBackEnd"
    }

EnginioModel {
        id: paisEnginioModel
        client: clienteEnginio

        query: {
            "objectType" : "objects.pais",
            "sort": [{"sortBy":"updatedAt","direction":"desc"}],
            "query": {"updatedAt": {"$gt": {"$type": "time","$value": getYesterday()}}},
            "limit": 15
        }
        property string text: updatedAt
    }

    function getYesterday( ) {
        var today = new Date();
        today.setDate(today.getDate()-5)
        return Qt.formatDate(today, "yyyy-MM-ddT00:00:00Z");
    }

[clochydd]

Hello,

in my example I used updatedAt as this is one of the internal properties.
Therefore it is not necessary to declare it as a property.
Instead of it you may use any of the properties from your enginio object.
If you have "name" you may use it without any further declaration in your model.

Just try to delete the entry "property string..." and try to use it with your clienteEnginio.

[guidupas]

@clochydd

It returned this:
Cannot assign to non-existent property "text"

Here is the code:

EnginioModel {
        id: paisEnginioModel
        client: clienteEnginio
        /*query: {
            "objectType" : "objects.pais",
            "sort": [{"sortBy" : "nome","direction" : "desc"}],
            "query": {"nome": {"$gt": {"$type" : "string","$value": "Brasil"}}},
            "limit": 15
        }*/

        query: {
            "objectType" : "objects.pais",
            "sort": [{"sortBy":"updatedAt","direction":"desc"}],
            "query": {"updatedAt": {"$gt": {"$type": "time","$value": getYesterday()}}},
            "limit": 15
        }

        text: updatedAt
    }

[clochydd]

Did you assign your enginioModel to your ComboBox?

ComboBox {
    width: 200
    model: paisEnginioModel
}

[guidupas]

@clochydd

Yes, here it is:

EnginioClient {
        id: clienteEnginio
        backendId: "MyId"
    }
    EnginioModel {
        id: paisEnginioModel
        client: clienteEnginio
        query: {
            "objectType" : "objects.pais",
            "sort": [{"sortBy":"updatedAt","direction":"desc"}],
            "query": {"updatedAt": {"$gt": {"$type": "time","$value": getYesterday()}}},
            "limit": 15
        }

        text: updatedAt
    }
    ComboBox {
        id: comboBox1

        model: paisEnginioModel
    }

It returns this message:
QQmlApplicationEngine failed to load component
qrc:/main.qml:70 Cannot assign to non-existent property "text"

[clochydd]

You should not use text: updateAt inside your model.
(In my first post this was only meant as an example...)

By assigning the model to the ComboBox the properties from the model are part of the ComboBox.

If you look at the ComboBox example:

ComboBox {
    width: 200
    model: [ "Banana", "Apple", "Coconut" ]
}

[ "Banana", "Apple", "Coconut" ] will be replace by your paisEnginioModel.

[clochydd]

Hi guidupas,

until now I didn't use a ComboBox with QML and Enginio, so I've made this small example:

Assume, we have a collection objects.contacts with custom properties name and address:

{
  "name": "Peter",
  "address": "Somewhere"
}
{
  "name": "Peter",
  "address": "Anywhere"
}

and we want to see the addresses for all Peters in the ComboBox:

import QtQuick 2.3
import QtQuick.Controls 1.2
import Enginio 1.0

Rectangle {
    width: 500; height: 200

    EnginioClient {
        id: client
        backendId: "myBackendID..."
        onError: console.log(reply.errorCode + ": " + reply.errorString)
    }
    EnginioModel {
        id: eModel
        client: client
        query: {
            "objectType": "objects.contacts",
            "query" : {"name": "Peter"}
        }
    }
    ComboBox {
        model: eModel
        textRole: "address"

    }
}

And your ComboBox will contain:
Somewhere
Anywhere

Hope, it helps a bit...

[guidupas]

@clochydd

It worked fine.

Thank you very much. It helped a lot.

[guidupas]

@clochydd

Hello @clochydd !

I heard that Enginio is going to be deprecated. Do you know if this is true?

Cheers.

[SGaist]

Hi,

AFAIK, the talk is about the client library, not the service

[clochydd]

Hi SGaist,

thanks for your comment - is there any information available in the forum or elsewhere? I wonder about the consequences, if the client library will be deprecated.

[SGaist]

Currently I only saw this on the mailing list. If that be the case, it will be properly announced. The deprecation just means that there won't be further development on the client part except security related stuff. The code itself isn't going to disappear.

[Charby]

I was just starting to learn engin.io but according to the 5.6 roadmap the module will be deprecated http://wiki.qt.io/New_Features_in_Qt_5.6). What would be the recommanded way to communicate with an EDS backend from a qml mobile app? Even if the api will remains I feel it is not advisable to start a new project with an ingoing deprecated module...

[clochydd]

@Charby
You are absolutely right! And it seems to be quite strange to see Digia propagating Enginio on their current web presence while planning to remove Qt Enginio...

[SGaist]

From https://developer.qtcloudservices.com/eds/references/sdk-libraries It looks like there's something in the work.

[Sajad Manal]

@SGaist Sir I am new to qt . I didn't know where to ask to I am givingmy question here:

I downloaded qt-opensource-linux-x86-5.4.1.run but how to install it on ubuntu 14.04LTS?