Sweep functionality documentation request

[xalier1]

Describe the bug
Ping sweep functionality is disabled unless ping is called with size=None or size=0

To Reproduce
Steps to reproduce the behavior:

1. Call ping without size=None - ret = ping(ip,sweep_start=10 ,sweep_end=109,timeout=2,match=True)
2. Use wireshark or equivalent and look at the icmp messages being sent
3. Observe that payload is all the same size, equivalent to ping being called with size=1
4. Call ping with size=None - ret = ping(ip,size=None,sweep_start=10 sweep_end=109,timeout=2,match=True)
5. Use wireshark or equivalent and look at the icmp messages being sent
6. Observe that payload size is now changing from one icmp request to the next

Expected behavior
It wasn't clear from the documentation that in order to use sweep functionality that ping must be called with size explicitly set to None or 0. Please update the documentation to make this clear.

[alessandromaggio]

Hello!

You are making a good point. I will try to verify it, but if that's the way it is, rather than updating the documentation, I think the correct behavior, I would make it ignore the size parameter if the sweep sizes (start and end) are set instead. The problem is happening because the default size is 1 most probably.

[xalier1]

Hi

Thanks for your quick response. I appreciate being able to use the ping functionality of pythonping module. Thanks for authoring, maintaining it and making it available on github. Included below is a response to your response and an additional discussion item.

As you have said in your response, giving the sweep sizes priority over size and count if sweep sizes are set makes sense as a better solution. I am new to Python but it seems that since both size and count can conflict with sweep sizes, an alternate better solution might be to resolve the conflict programmatically in the ping function. As a suggestion would the following work? Default both size and count to None as is already done with sweep_start and sweep_end. If a call to ping is made with a conflict like sweep sizes set and size set, raise a ValueError('with explanation of the conflict') exception. If ping is called and sweep sizes are not set, and count and size are not set, then programmatically set size=1 and count=4 (eg the current defaults). Adding a ValueError exception on a parameter conflict rather than being silent about the conflict would seem like a good thing to do.

As a discussion item, I was wondering why the sequence number is not matched between request and response when ping is called with match=True. It would be convenient for me if match=True could be redefined to do this. I am currently using the sweep functionality to force a match between request and response. The sweep functionality is very useful but for my current application, if match=True included sequence number match, then I would not be using sweep functionality.

[alessandromaggio]

In the end I simply inverted an if-elif construct in the ping function. Now if you set sweep_start and sweep_end, size is ignored, which is the correct behavior as setting a static size and sweep settings make no sense, so I am assuming this is the wanted behavior for most users.

Changes are already out in version 1.0.16, which is already available for download with pip. I am going to close this, thanks for the clear notification of the issue and good pinging! And if you have time, feel free to pick an open issue and contribute :)