Email reports: pcharts licencing

Hi Tristan,

Does the email report include any graphs?

We have been working on something similar using pChart to include graphs in our email reports. This saves the graph image as a png on our local server so the graph image can be included in the email. It is a loop for each solar account saved. Happy to add it to the project. I’m not sure about the licence rules for pChart. Maybe we can find another graphing tool for it to work.

Kind regards,
P.S. Thank you for keeping this project running. It is amazing.

From pChart 2.0 - a PHP charting library

The pChart library is released under two different licenses. If your application is not a commercial one (eg: you make no money by redistributing it) then the GNU GPLv3 license (General Public License) applies. This license allows you to freely integrate this library in your applications, modify the code and redistribute it in bundled packages as long as your application is also distributed with the GPL license.

If your application can’t meet the GPL license or is a commercial one (eg: the library is integrated in a software or an appliance you’re selling) then you’ll have to buy a commercial license. With this license you don’t need to make publicly available your application code under the GPL license terms.

Thanks for that help Bill. Does that mean that PChart can be included in EmonCMS github?

Given the part about needing a license for integrating it into a device that’s sold, I’d say no.
(emonCMS is on SD cards the Shop sells)

Best thing to do is ask the pChart folks.

AH yes, good point Bill. If we come across a similar graph tool we will suggest it to the post.

You could also ask @glyn.hudson or @TrystanLea what the price for the SD card covers. As the content is free to download (if you put it all together yourself), it might be possible to argue that the software is free and the cost of the card is materials plus the cost of writing the card, and therefore the application is not commercial. Probably the best route is ask T&G first, then go to pChart with their answer.

The software is free. The cost for the SD card is just to cover the material cost and manpower to flash the card .

The SD card images can by build yourself or downloaded for free: emonSD pre built SD card Download & Change Log · openenergymonitor/emonpi Wiki · GitHub

@Alexander_Robinson pchart sounds interesting. Any contributions would be appreciated. Emails would certainly benefit from a graph.

Couldn’t one also argue that the card is integrated in an appliance? e.g. when included with an emonPi?

Now that we have a definitive statement that the cost for the SD card covers only materials and labour, surely the right thing to do is put the question to the owners of pChart for their ruling?

That’s the next step. My guess is a license is needed because the code is included in an appliance that is for sale.
But you never know, they may well say it’s OK.

Interesting, While we may question the exact commercial status of emoncms on the SD card, the intention is that emoncms should be able to be used commercially. GPL and GPL Affero both allow commercial use. Our interest is to keep the software open source regardless of whether its used commercially or not.

Shall I split this thread into a separate thread titled “email reports: pcharts licencing?”

Good idea, I’ve just done it :+1:

Just to clarify the application (Emoncms) is not for sale. Emoncms is fully free and open-source and always will be.

I can’t see this being an issue at all. It’s quite common to have to pay a fee for physical medium to cover the physical cost. E.g in the past you could choose to download a Linux distro for free (which would take a long time over 56K modem!) or pay for a CD install version. This does not change the license status, no software is being sold.

I agree with your argument, Glyn, but I still think that to avoid doubt…

We might even be listed as a user and get a plug from them! There’s a “They’re using it” on the home page.

Quite true, but the possible gotcha is the part that says integrated into something you are selling.

As Robert said, the thing to do next is ask them. As I mentioned earlier, they may well be OK with it as is.
You won’t know unless you ask.

My understanding of ‘commercial use’ is not necessarily a question of whether the software itself is sold but whether the software is used commercially. I.e a solar pv installation company using emoncms as part of a commercial service, or indeed our use of it commercially ourselves - as it is bundled in a commercial product (emonbase/emonpi/SDcard).

Yes I reckon its worth asking pcharts whether they can allow pcharts to be used within emoncms under GPL even if its then used commercially.