On Mon, Jun 21, 2010 at 10:40 PM, Rainer Gerhards <[email protected]>wrote:
> Hi all, > > thanks again for the good feedback. Please keep it flowing, I guess we will > hit a first milestone very soon. Then, I think, we have a format that we > could work towards and begin to look at some details. > > I have now condensed the comments and thought about them. Then, I have > looked > at some ways how config files could actually look like. What then hit me > was > that we are very close to how XML looks. For example we had: > > <input name=inp10515 type=imtcp> > listen 10514 > ruleset remote10514 > </input> > > this almost looks like XML (which is no surprise given the fact that > Apache's > config also looks somewhat like XML and we talked about modifications that > are a bit more in the spirit of XML). The step towards full XML is not a > big > one (intentionally formated close to non-XML example): > > <input name=inp10515 type=imtcp> > <params listen="10514" > ruleset="remote10514" > /> > </input> > > While I am not a big fan of XML config files, I have to admit that the > difference between what we discussed, at least in a later stage, and XML is > slim. Seeing this, I begin to think that using an XML-based config language > has a number of advantages. Probably the most important being that I do not > need to write an maintain a dedicated parser but could use a XML-Parser > instead. Plus a validating editor could probably be a good aid in writing > config files (assuming that I get the DTD right, something I have no > experience in ;)). > > So I have converted my original proposal (NOT the last discussion state) > into > XML format. Again, I think the XML version is quite readable. Please have a > look > > Original: http://www.rsyslog.com/download/new_rsyslog.conf > XML: http://www.rsyslog.com/download/xml_rsyslog.conf > > I wonder if there is any good argument AGAINST using XML as "described" in > the sample. If nobody brings up a good argument, I'll very possibly will > try > to take the XML road and begin to look what that takes in detail. Of > course, > it would be helpful as well if you could make yourself heard if you like > XML > format ;). XML might be better than some apache-like format because: - editors will automatically do syntax-highlighting, which greatly improves readability. If you add <?xml version="1.0"?> as the first line of xml_rsyslog.conf then editors will notice it's XML, despite the unusual extension (I've tested vim, emacs and gedit). Editor support also gives you nice things like auto-intending (=G in vim) and folding. - there are some fantastic XML validation languages - see http://www.relaxng.org and http://www.dsdl.org. Fancy editors will autocomplete based on the contents of these validation files. - XML is natively unicode with a well-defined means of setting the encoding, and parsers will handle all that for you. Just wondering, is it necessary to have all those 'params' elements? Could this: <input type="imtcp"><params listen="10515" ruleset="remote10515" /> </input> just become: <input type="imtcp" listen="10515" ruleset="remote10515" /> Overall though, after the initial curve I've come to quite like the old format :) A good format is one that is optimized for common cases. For syslog that is simple statements like: mail.* -/var/log/mail.log user.* -/var/log/user.log which becomes very verbose under XML: <ruleset id="default"> <rule> <filter pri="mail.*"/> <action type="omfile"> <params file="/var/log/mail.log" sync="false"/> </action> </rule> <rule> <filter pri="user.*"/> <action type="omfile"> <params file="/var/log/user.log" sync="false"/> </action> </rule> </ruleset> Anyway, if you do go the XML route I don't think the work would ever be wasted. An XML DOM is generic enough to act as an AST for any future formats. Anyone wanting a different format (eg. YAML or Sieve-like) can simply generate the XML DOM and pass it in. Jeff > I am looking forward to your feedback! > > Thanks again, > Rainer > _______________________________________________ > rsyslog mailing list > http://lists.adiscon.net/mailman/listinfo/rsyslog > http://www.rsyslog.com > _______________________________________________ rsyslog mailing list http://lists.adiscon.net/mailman/listinfo/rsyslog http://www.rsyslog.com
