DEV Community: Dhanush

Build a terminal ChatApp using python.

Dhanush — Thu, 30 Jan 2020 11:51:57 +0000

Establishing a successful communication between two or more devices is always a great joy. While I was working on a project I needed to satisfy some requirements. Like, to group certain devices and make communication only between them (chat rooms or group chat). For chatting applications obviously we need a socket protocol. So python has this awesome library called socket.io. This is a python implementation of Nodejs Socket.io.

So the basic idea is to create a server that handles the client messages and delivers to the targeted client. We'll create a aiohttp server which is asynchronous and solves many problems.

Before we start creating a server. Let's set up the python environment.
The python version which I am using is 3.7.9

It is recommended to use python-3.6.+

Install the following libraries

Now we're good to go.

Let's setup the server first.

What's basically going on here is, we just take an aiohttp server and attach it to a socket-io object. Where there will be a connection upgrade and much more. Let's not get too deep into that. We can also see that every function has a @sio.event decorator. It just helps in executing the respective function according to the emitted event.

Now run the server with the command python server.py
After running it should look something like this.

The URL http://0.0.0.0:8080 represents the default route. So that every machine or device on this local network can access the server.

That's it. The server part is done. Now let's move on to creating clients.

Before running clients know your IP Address in Linux it's ifconfig in windows it's ipconfig.

Client codes is shown below.

Client 1

Client 2

So we created 2 clients with names Deadpool and Iron man who belong to the same room called Marvel.

Here the communication happens only in Marvel room. If Deadpool and Iron man are in different rooms the communication is not possible.

So let's test it.
When client codes are executed we can see that server logs the name of clients that are connected.

That's it. You can start typing in the terminal itself and hit enter to send.

thegoliathgeek / Terminal-ChatApp

Terminal Chat App

Blog Link

Note :- `Use python 3.6.+ or above`

Install Required libraries

For more detailed explaination click here

View on GitHub

Automation with Alexa using nodejs.

Dhanush — Wed, 18 Dec 2019 06:12:02 +0000

Hi, as we saw how to automate devices with python and Alexa in the last tutorial. We'll move forward with nodejs for automating things.

So, again we are using sinric pro as Alexa's skill for automation. Which is free and easy to implement.

We'll keep this tutorial short and simple ;).

1. Signup

Goto sinric pro website and signup.
Verify your email.

2. Create devices

Click on the Devices button on the sidebar.
Then select Add Device.
Select which device type you need and let the access key be the default for now.
That's it.

3. Linking sinric pro to Alexa

Goto to Alexa's skills & games and search for sinric pro skill.
As soon you link the skill you will be redirected to the login page.
Login with the credentials which you used signup for sinric pro website
After successful login just go back to your Alexa app and it'll start discovering the devices which you added in sinric pro account.
So linking skill is done.

4. Integration with nodejs

Installing nodejs library for sinricpro
```
npm install sinricpro --save
```
You can find the source code for the nodejs library here.

Initializing with access key and secret key

Let's see how to get these keys.

Login to sinricpro here
Click on credentials button on the sidebar.
There you'll find 2 keys. One is app key and another is secret key basically app key is used to provide API service. secret key is used to provide security for the information exchanged between devices.

Getting device ids.

Device IDs are the unique ids that are used to differentiate between devices.
As you can see there are 2 more fields fan and light in the code above.
Go to the devices page here.
Copy the device ID as shown below and paste it in the code.
Done.

So moving forward, let's see how to connect to sinricpro. Basically there are 2 ways for controlling a device with sinricpro.

Action.
Event.

Action

Action is something that Alexa does for you. Like when say Alexa, turn on light or when you control device from website or app.

Event

Event is used to control the device manually. Like when you press a button so light should change its state or much more.

Defining action and event callbacks

Next step is to initialize the library with callbacks

Let's see how a complete code looks like.

That's it ;). When you run the code your devices will be online (status turns to green from red) you can control them with Alexa or website portal or app.

For more help, click here.

Feel free to comment if any corrections or any doubts.

Thanks :).

Automation with Alexa using python.

Dhanush — Mon, 16 Dec 2019 09:23:06 +0000

Hi, Being an electronics and programming enthusiastic, I always wondered how can I automate my room appliances (not with smart bulbs). There were many different ways to come up with like Bluetooth, LAN, MQTT, etc. Then I thought of automating with Alexa for existing devices. There are 2 ways of doing it. The easy way and the hard way. So, for now, let's talk about the easy way.

There are a lot of automation skills in the Alexa skill store but most of them support smart devices. After doing some research I found a really good skill called sinric which let's me control existing appliances with some extra circuitry. Thanks to Aruna Tennakoon for providing this feature. Setting up this skill is straight forward.

Signup
Get API key
Add skill to your Alexa
Use these examples
That's It.

Sinric is the 1st version with many kinds of device supported. Recently 2nd version of sinric is up which is called sinric pro. We'll discuss the latest version.

let's see how to set up the skill.

1. Signup

Goto sinric pro website and signup.
Verify your email.

2. Create devices

Click on the Devices button on the sidebar.
Then select Add Device.
Select which device type you need and let the access key be the default for now.
That's it.

3. Linking sinric pro to Alexa

Goto to Alexa's skills & games and search for sinric pro skill.
As soon you link the skill you will be redirected to the login page.
Login with the credentials which you used signup for sinric pro website
After successful login just go back to your Alexa app and it'll start discovering the devices which you added in sinric pro account.
So linking skill is done.

4. Controlling devices with Alexa

Here's where the coding part begins.
Sinric Pro has supporting libraries for python, c++(nodemcu), nodejs.
Let's start with python.

5. Integration with python

Installing python library for sinricpro
```
pip install sinricpro
```
You can find the source code for the python library here.
Just a reminder. This library is only supported for python versions 3.7+.

Initializing with access key and secret key

Let's see how to get these keys.

Login to sinricpro here
Click on credentials button on the sidebar.
There you'll find 2 keys. One is app key and another is secret key basically app key is used to provide API service. secret key is used to provide security for the information exchanged between devices.

Getting device ids.

Device IDs are the unique ids that are used to differentiate between devices.
As you can see there are 2 more fields fan and light in the code above.
Go to the devices page here.
Copy the device ID as shown below and paste it in the code.
Done.

So moving forward, let's see how to connect to sinricpro. Basically there are 2 ways for controlling a device with sinricpro.

Action.
Event.

Action

Action is something that Alexa does for you. Like when say Alexa, turn on light or when you control device from website or app.

Event

Event is used to control the device manually. Like when you press a button so light should change its state or much more.

Defining action and event callbacks

Next step is to initialize the library with callbacks

Let's see how a complete code looks like.

That's it ;). When you run the code your devices will be online you can control with Alexa or website portal or app.

For more examples, click here.
For more help, click here.

Thank you :).

DEV Community: Dhanush

Build a terminal ChatApp using python.

It is recommended to use python-3.6.+

Install the following libraries

Client 1

Client 2

thegoliathgeek / Terminal-ChatApp

Terminal Chat App

Note :- Use python 3.6.+ or above

Install Required libraries

For more detailed explaination click here

Automation with Alexa using nodejs.

1. Signup

2. Create devices

3. Linking sinric pro to Alexa

4. Integration with nodejs

Let's see how to get these keys.

Getting device ids.

Action

Event

Automation with Alexa using python.

1. Signup

2. Create devices

3. Linking sinric pro to Alexa

4. Controlling devices with Alexa

5. Integration with python

Let's see how to get these keys.

Getting device ids.

Action

Event

Note :- `Use python 3.6.+ or above`