Information on App developer projects

[RGV250]

Hello,
I have decided I need to look at primarily web developer for a project. There are 2 that seem to be close to what I hope to do so downloaded the documentation and had a look.

For the environment monitoring - web and PC developer, it states This data is received and displayed by a PC Developer app and a Web Developer app.
Is this either or does the web app need the PC app for the data?
The pictures show the PC app similar to the web app but also has status "Connected, Subscribed" where the web app does not which seems to imply the PC app is needed? Or was it just overlooked?

For the HTTP Comms Worked Example - Web Developer, this does not have the PC app but also does not have logging, is this because the PC app does the logging?

Looking at the other examples that do logging Mains Power Monitor - PC Developer and 3-Channel Temperature Logger - both are PC Developer so it seems that the web developer / app cannot do logging?

Regards,
Bob

[medelec35]

Hi Bob.
I have recently developed a web app that has a line chart and updates the data every 10 seconds.
The web developer can log.

Data Logging2.png (82.67 KiB) Viewed 400 times

I used a TTGO ESP32 which connects to my WiFi.
Connected to the ESP32 is a DS18B20 used for sending the temperature data.
It not only displays the temperature on the gLCD, it also sends the data to the web app via HTTP when requested by the HTML webpage.
I'm not using PC developer at all for this project.
I can help you with your project.

I would suggest to do what I did, when I fist learnt.
Start off with something simple e.g. log an ADC pin, then log two adc pins.
Just build up from there.

[BenR]

Hi Bob,

Aha Martin beat me to it

The PC app and Web app are not interdependent, they are either or.

The PC app has access to the file system and so can stream data to a file fairly easily as it becomes available.

The web app does not have access to the file system for security and so you would need to maintain your data in a string or array and then dump the data to a log in one go. This appears to the user as a file download where they can choose where to save the file. There is a new component now available which lets you do this called Create File. You can also store things into session data using the Storage component.

Another option might be to log to something external e.g. a remote MQTT server.

[RGV250]

Hi Martin, Ben,
Thanks for the replies, the project I have in mind is my energy monitor, originally I had it working in Node Red but that was rather buggy.
I then had it working (reading data) and displaying it on a web browser in FC but not very well (the web side). I mothballed it as I was getting a smart meter but now I have it I can see the in house display was developed by a "Fisher price" programmer and absolutely useless.
It does not need to store historical data but I am looking for a trend for around the last 60 minutes of approx 5 second samples so around 720 records.
It will be on a Raspberry Pi later but due to the examples on ESP32 I plan to develop on that first. I have an SHT31 as well so the environment monitoring example will be a good start, as soon as I understand that I will try to change the data source.
I am a bit wary of external things like MQTT as that can be taken away or stopped developing but locally should be fine.

Regards,
Bob

[BenR]

Hi Bob,

I can see the in house display was developed by a "Fisher price" programmer and absolutely useless.

I feel your pain, mine is terrible too. Worst still the company that created these abominations likely got paid a small fortune for it!

I have a MQTT server running on a RPI locally which is nice as I can bounce a load of sensor data to it and then access it locally via my phone etc as well as store it into a mysql database on the Pi. It's an option for later on anyway

Sounds like an interesting project, let us know how you're getting on.

[chipfryer27]

Hi

Well over a decade ago a recruitment company asked if I would be interested in joining a team developing smart meters. Decent money, and I got the impression they were struggling for staff. I didn't follow up on the offer so at least I'm not to blame.... Actually I should have and then put in an evil back door that would allow access to manipulate...... for a fee. At least my access would be for my financial gain and not to switch it all off under foreign control......

Much like Ben I created a RPi MQTT broker and a RAMP install which runs very well on older models such as a headless 3B. Very stable. I posted either in this or old forum a guide and examples which may be of use. I had very little success in running ThingsBoard on a 3B though, which I put down to lack of resources. I've just grabbed a 500 which is a very capable beast (and also a Zero 2W) and I'm hoping to get ThingsBoard running on it. Well when I get time.....

Regards

[RGV250]

Hi Martin,
I have an example working on ESP32, I also have the code on a Raspberry Pi which reads the data from the monitor.
I am now in a quandry whether to try to migrate the ESP code to the Pi or the Pi code to the ESP. A decision made after a few beers I think.
I also have printed the web developer getting started guide so a lot of beers tonight.

Hi Ben,
The historic chart you mentioned in another post looks like what I need but as Chipfryer has mentioned, it does not appear to be available for the web app. The other thing I was going to look at was the XY chart and circular buffer (used in a couple of examples) but they are not available either.

Regards,
Bob

[medelec35]

I am now in a quandry whether to try to migrate the ESP code to the Pi or the Pi code to the ESP.

Personally I would favour ESP32 over RPI.
Pi is big and overkill and does not have analogue functions.

[chipfryer27]

Hi

Not quite sure what you intend to do. For a small form "sensor" then most likely the ESP32 if you don't mind espressif changing goalposts at random, or almost any other microcontroller using an ESP8266 for WiFi. Pity there is no support for Pico 2W as that would offer a great alternative that doesn't rely on espressif.

However to collate and store data the RPi wins hands down, being able to reliably handle many tried and tested solutions such as MySQL / MariaDB / PHP / ThingsBoard / MQTT with or without a GUI. Indeed you can have multiple services running concurrently such as MQTT and MariaDB etc. Simple enough to add in a cheap ADC board or the like and be self contained. Very easy to have this as a hub and have other wifi devices talk to it.

If using RPi as a server, broker or hub, then I would personally suggest a 3B onward. These still hold their value going by auction sites. As mentioned in another post, having just aquired a 500 I'm keen to try and install the community edition of ThingsBoard on it.

Regards