Module talk:IP
Plan
A discussion at WP:Lua (permalink) led to the creation of this module with a plan for a general-purpose IP address handler. I pointed out that Module:IPblock (which implements {{blockcalc}}) includes functions that can extract IPv4 and IPv6 IPs from text arguments, and convert IPs for text display, and can do various calculations including determining the best available CIDR block summary of given IPs.
Apart from the advantage of having a general-purpose IP handler, the immediate requirement was for a module that could generate the list at {{Sensitive IP addresses}} and output identical information for use by MediaWiki:Group-sysop.js.
I am contemplating how functions from Module:IPblock might be used here, and these are my preliminary thoughts. General purpose handling of CIDR blocks is tricky and I built in a restriction to make implementation easier. The module accepts individual IPs (IPv4 and IPv6), and CIDR blocks (IPv4 only, and only of form IP/n where n is 16 to 32 inclusive—that is, 65,536 addresses or fewer). The module puts the IPs in two lists, one for v4 and one for v6, then processes each list. Each list is sorted and duplicate IPs are removed (that's helpful for the user and necessary for the method used to create summaries). Then summaries are generated and the results displayed in a table.
A key point is that each CIDR block is expanded to individual IPs: for example, 1.2.3.224/27 would be expanded to 32 individual addresses (1.2.3.4.224 to 1.2.3.4.255 inclusive). That is done because the method used to create summaries needs a list of individual IPs.
It would be possible to work with CIDR blocks without expanding them, but I suspect the code complexity would blow out, and it's already pretty fierce.
The outline in Module:IP is great, and I initially contemplated something like that, but pragmatism overtook me and I did what was needed for {{blockcalc}}. A more general module would be good, but some of the proposed methods may be difficult to implement. I'm thinking of IPBlock removeIPs—if the input is 1.2.3.224/27 and 1.2.3.243 is removed, the result is 31 IPs which can be summarized as four CIDR blocks and an IP, as shown by blockcalc (this is the result of passing the 31 IPs to {{blockcalc}}):
Sorted 31 IPv4 addresses:
- 1.2.3.224 – 1.2.3.242
- 1.2.3.244 – 1.2.3.255
| Total affected |
Affected addresses |
Given addresses |
Range | Contribs |
|---|---|---|---|---|
| 32 | 32 | 31 | 1.2.3.224/27 | contribs |
| 31 | 16 | 16 | 1.2.3.224/28 | contribs |
| 2 | 2 | 1.2.3.240/31 | contribs | |
| 1 | 1 | 1.2.3.242 | contribs | |
| 4 | 4 | 1.2.3.244/30 | contribs | |
| 8 | 8 | 1.2.3.248/29 | contribs | |
The module would either have to keep a list of each individual IP (what Module:IPblock does), or maintain a list of blocks—possible but awkward.
Before starting the implementation, can we discuss the plan. Are addIPs and removeIPs wanted? For any number of IPs?
My pragmatic side also wonders whether the implementation effort would be worthwhile—would it actually be used? The requirement for sensitive IPs probably does not need the generality, and it might not need a module that can process IP addresses at all (although I haven't looked at what is needed for the js output). Johnuniq (talk) 11:03, 14 July 2016 (UTC)