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Servicemon is currently hidden away inside SeedDB. Now that a rewrite of SeedDB is being considered, this is a good time to take Servicemon out and make it a separate tool with its own web interface. This will make it more visible to users. The code should also become easier to work with, since it's no longer tied to the rest of SeedDB.
The backend will not need to be rewritten, except to add support for help text.
The current interface is a little weird in places. The goal should be to make the new interface as obvious as possible.
Most checkers and arguments are pretty easy to figure out how to use, but some are decidedly more obscure, such as the RPC checker which takes an optional argument named 'required'.
Adding a checker could look something like this (if you imaging that this is html):
New Dippedutt checker on tjobing.not Sends a bunch of DIPP request to a whole subnet over the DAPP protocol, and returns UP if it gets at least one reply. Requires dippedutt-client 0.92 or higher. REQUIRED ARGUMENTS: Mask: [192.168.0.0/16] IP mask of subnet to spam OPTIONAL ARGUMENTS: Port: [ ] TCP port Timeout: [3 ] (in seconds) [Save]
Maybe the help text should be on top or to the right. What's important is that it is available when you need it, but out of the way when you don't. (Mouse-over help will not be obvious to users. It should be visible on-screen without any action from the user, if it doesn't clutter the page too much.)
All help text should be stored in the .py file, so each checker is one completely self-contained file.
Move everything into the .py file.
The description, required args and optional args of each checker is stored in a .descr file. This file is only used by SeedDB (really?). If the Servicemon web page is rewritten, this information could be moved into the .py file, for example like this:
class DippeduttChecker: ... description = 'Dippedutt' required =  optional = 
The module should also contain help text for the checker and for each argument.
from statemon.checker.something import Arg description = 'Dippedutt' help = 'Checks a dippedutt using DIPP requests over the DUTT protocol. Requires dippelidapp 1.0 or higher, which must be setuid root.' required = [Arg('opt', help='')]
Maybe the Arg() bit is a bit verbose, but the help text has to go somewhere, and it allows things like type=int etc. to be added later.
.descr files are only used in Servicemon, so the parser is not used anywhere else. (Or is it?)