artanis.conf user defined variables

[Mortimer Cladwell]

Hi Nala,

My artanis app makes use of a custom variable, let's call it "maxnumwidgets", that I would like to include in artanis.conf to give the users an easy way to configure.  Currently I do this by modifying the source during install with the following snippet in the guix packaging recipe:

 (substitute* "artanis/config.scm"
      ((" \\(else \\(error parse-namespace-cache \"Config: Invalid item\" item\\)\\)\\)\\)")
"(else (error parse-namespace-cache \"Config: Invalid item\" item))))\n\n(define (parse-namespace-cookie item)\n  (match item\n    (('expire expire) (conf-set! '(cookie expire) (->integer expire)))\n    (('maxnumwidgets maxnumwidgets) (conf-set! '(cookie maxnumwidgets) (->integer maxnumwidgets)))\n    (else (error parse-namespace-cookie \"Config: Invalid item\" item))))"))

maxnumwidgets is not a cookie.  I put it in the cookie group for convenience.  I can imagine an artanis.conf section that looks like:

##user defined variables

##user.var1 = <string>
##user.var2 = <string>
##user.var3 = <string>
##user.var4 = <integer>
##user.var5 = <integer>
##user.var6 = <integer>

This would provide the developer with a few configurable variables that don't require modification of the source code.  The developer would have to document the meaning of each variable, for example I would have to indicate in documentation that user.var1 == maxnumwidgets.  I can write the source modifications and create a pull request, but don't want to put in the effort unless you are interested. Let me know.

Thanks
Mortimer