httpClient() question

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I'm working on communicating data to a Diagraph IJ4000 packaging line printer. Right now I've settled on using system.net.httpClient() to send the data. The scripting is very basic, as the printer has built-in cgi scripts where all I'm doing is sending a GET and the URL that includes the target cgi and any data parameters.

My Project script looks as such:

# Create the JythonHttpClient.
client = system.net.httpClient()

def loadDiagraph(ipAddress,printTemplate,lotNumber,mfgDate,expireDate):
		#Send Data & Start Print requst 
		client.get("http://"+ipAddress+"/serial.cgi?idx=0&nme="+printTemplate+"&fst=1&lst=3&d1="+lotNumber+"&d2="+mfgDate+"&d3="+expireDate+"&net=1")

I'm then calling the script from inside a "Load Printer" button I've placed on a screen.
This works without fault, but I've read through multiple forum threads about being careful with calling the system.net.httpClient() too much or in specific scenarios - most of which is beyond my current knowledge and I'm not understanding.

Right now we're testing a single printer, but I could end up with as many as 6-7 line printers which I'll need to send data to in this manner.

Is there a way to see if I've opened too many connections? Do I need to close the connection(s) somehow after sending the data? If so, how?

Thank you for any assistance!

2

You're fine. You created the client variable outside any function definition, making it shared across all callers. Which is precisely what you should do.

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The concern is more something like "creating an instance of httpClient every single time a particular button is pressed in a Perspective project" - which means you're creating an instance per session multiplied by the number of times end users click the button - very quickly getting out of control and potentially exhausting system memory and other OS level limitations as those clients hold on to additional memory and thread pools.

It's such a concern that in 8.3 there's going to be a 'default' HTTP client instance mounted as system.net.httpClient - you'll still be able to construct your own, but for simple cases that don't need customization like your example above, you'll be able to just use system.net.httpClient.get(url).

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Thanks for the insight!