Make fun things with your home IoT devices, securely over the internet.

I am planning to start a series of posts discussing how to put your IoT devices in the internet and do fun stuff with them. I will provide them as GitHub Wiki pages and I will also provide code and scripts when this is possible. This page will act as a placeholder.

Interact using Alexa with your IoT devices

In this first post I am using the excellent, free, Cloudflare Tunnel and I make my Raspberry Pi accessible over the internet using a custom domain and HTTPS. Only with a few clicks and no cost (apart from the cost of the domain name).

Then I provide an Amazon Alexa Skill that can be used for interacting with your Raspberry Pi using your Alexa device! In this simple example, I am implementing a simple REST API which is invoked using voice commands.

Have fun!

A CoAP server for the riot operating system using libcoap

View a list of all libcoap examples here.

The riot operating system (https://riot-os.org/) is an operating system for the Internet of Things that currently supports many platforms. One of the main advantages of riot is that it supports programs and libraries written in C including libcoap.

In this github repository you will find an example of a CoAP server for the riot operating system https://github.com/nikosft/libcoap/tree/master/riot This server implements a default resource that outputs "Hello World!".In order to test the example, download the latest version of the rios os (https://github.com/RIOT-OS/RIOT), create a folder inside the examples directory and copy the code from https://github.com/nikosft/libcoap/tree/master/riot in that new directory. Then from a terminal type
$ make

If you encounter any problem, consult this riot wiki page https://github.com/RIOT-OS/RIOT/wiki/Family:-native In order to use the example you have to create a virtual interface in your linux machine. In order to do this invoke the following utility:
$ <riot directory>/dist/tools/tapsetup/tapsetup -c1

This utility will create a virtural interface and a bridge (for more information visit this wiki page https://github.com/RIOT-OS/RIOT/wiki/Virtual-riot-network). After this step, from the folder where you have put the example code invoke:
$ make term

This command will execute the binary created in the previous step and soon an ipv6 address will appear in the terminal. You can now access the coap server using the libcoap coap client and the displayed ipv6 address, by invoking the following command:
$ coap-client coap://[<ipv6 address>%tapbr0]

Asynchronous CoAP request-response using libcoap

View a list of all libcoap examples here.

This is an example of asynchronous request-response. The server listens on port 5683 (default port). When it receives a request for the "hello" resource, it sends and ACK and after 2 seconds it responds with a "Hello World!".

The client performs a CoAP GET request for the "coap://127.0.0.1/hello" resource and prints the response.

You can find the source code of this example, as well as, instructions for compiling it in Linux in this github repository, in the "seperate" folder.

A Hello World CoAP client-server using libcoap

View a list of all libcoap examples here.

This is a simple example of a CoAP server and a CoAP client. The server listens on port 5683 (default port) and responds with a "Hello World!" to every request for the "hello" resource. The response is piggybacked in the ACK message.

The client performs a CoAP GET request for the "coap://127.0.0.1/hello" resource and prints the response.

You can find the source code of this example, as well as, instructions for compiling it in Linux in this github repository, in the "piggybacked" folder.