Help Needed with Python and Web Client for Education

Question

So I have been tinkering with Raspberry Pis for a little while now, and I am thoroughly convinced of their utility, and I am hoping to spread that out in my classroom.

On example of a project I would like to do is taking temperatures using the waterproof temperature probe. There are many others, but that is a good place to start. My students make it a habit to bring their devices (phones, computers, tablets) to class, and it seems like I should be able to get their devices to control a probe on the RPi. The most obvious way to do that is through a web client.

So, I have some code I have been using for getting temperatures to report out to a Google spreadsheet by using gspread. You can find it here: https://github.com/MDScience/temperature

I would like to use it improve upon it with a web client so that my students could use their device to go to the RPi and tell the probe to start collecting temperature information once they are ready. I imagine there would be buttons and fields for required information (like the name of the file they would like to output to, and so on).

This, of course, is just the beginning. We would want to do more than temperature measurements, and we would need other sensors and other web clients.

If there is a good tutorial, or a model to follow I would greatly appreciate knowing about it. Similarly, if there are any engineers who have experience in this area, and would like to lend a hand, I would appreciate that as well.

Thanks!

shabaz · Answer

Hi Mike,

As I understand, you'd like students to use a browser to directly access their RPI (i.e. without using a cloud service)?

In that case, web server function needs to be implemented on the RPI. There are many ways to do it, here are some:

1. A popular method is to install apache which is an open source web server.

2. The above is quite heavyweight, so some people prefer using a different web server called lighttpd which is more suitable for the limited resources available

(There are tutorials on how to install/configure apache and lighttpd. You'd also need to know a minimum of html and possibly javascript to get clicking buttons and things working in the

browser).

3. It should be possible to implement a web server in Python alone (i.e. not install apache/lighttpd). It's not something I know about (I don't use Python) but I did

see this SimpleHTTPServer information so it is certainly possible. You still need some html (and Javascript probably) for this and all other methods.

4. Yet another method is to use Node.js and write your server application in JavaScript. It could call the Python program as needed, if you want to minimise code re-write.

I prefer approach (4), it is a great approach for a small web application. If you are familiar with Python then (3) could be considered.

By the way, if you're willing to wait a couple of days, then an approach (4) method will be published that could help start you off with some functionality.