Query WEB pages from PoE switch

Hello forum,

good evening. I'm new here and have a question about "querying" web pages from IOT devices.

I use a PoE switch from Microsens (MS450), which shows me the performance of the respective PoE ports. I would like to query this performance information via http request and html node.

The debugging gives me the following after the http request node:

Your Browser doesn't support Frames!
This page cannot be visualized.
Ihr Browser unterstützt leider keine Frames!
Diese Seite kann daher nicht angezeigt werden.
"

Can someone give me a hint what the problem is and what I have to change so that I can make progress?

Thank you in advance.

You need to open the page in your browser and see what it is actually doing. It looks like it loads a master page and then some iframes into that (v. old-school). You probably want to pick out the iframe URL instead of the master.

Hello TotallyInformation,
Thank you for your reply.

Yes, that is possible. I reach the first page in the browser without logging in.

When I log into the browser and select a "sub menu" on the left - this sub page is also displayed under the same URL. So no matter which page I select, the same address is always displayed in the browser address bar.

Do I perhaps have to insert other header information in NR?
But I have no idea about it.

Regards, myWa

if you have snmp maybe it would be more easy?

Thanks for the tip. Unfortunately, I have absolutely no idea about SNMP.

I don't know whether I can get the performance values from this PoE switch via SNMP and how I have to activate it.

But I'll take a look at this time.

Thanks again.
myWa

try looking under the Netwerkanalyse tab of the browser tools - It should show all the fragments it is loading into the frames. get to the page before you click the menu item - clear the log - then click the button to get the page you want and see what extra it is loading... That will have a url associated with each fragment... - one of them is probably the only bit you need to request - and hopefully you can just request it directly - by trying to cut paste that into another empty browser tab. Once you find the correct fragment - then you can put that back into the Node-RED request.. and then start slicing up the data to get to the bit you need.

Hello dceejay,
First of all, thank you for your reference. With your help I have come a little further. Yes, I think scripts are started.

The network analysis shows the following:

As I am not an expert, it is possible that this is not a good thing. Node-Red shows me the following result The result has been shortened. The fields for PoE power are not shown, but are included:

Is it possible to use this method to get the values?

Thank you and best regards,
myWa

Well - in one of those scripts there will be a call to the backend to get the actual data which it will then build the table with... it may have http:// in it - or maybe ws:// or may say get or ajax or open or fetch or somesuch... keep digging !

Hello dceejay,
you're right. I kept digging ... and found the following json:

In there is also the PoE power as a value. That is very nice.
"value"% 3A "8.4W"

The command begins with:
"data: application / json; charset = UTF-8,% 7B" name "% 3..."

My only problem now is:
How do I get this into node-red?
So how do I link the IP address / URL with this long line: "" data: application / json; charset = UTF-8,% 7B "name"% 3 ... "

The strange thing is that I get the value. Although no URL (IP address) is entered.
Where is the mistake?

Does somebody has any idea?

Greetings and have a nice Saturday evening,
myWa

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