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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hello Nathan,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>have you seen/read the wiki on Augeas' GitHub page already?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Read about how XPATH in used in Augeas:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><a href="https://github.com/hercules-team/augeas/wiki/Path-expressions">https://github.com/hercules-team/augeas/wiki/Path-expressions</a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>How you can insert new nodes to a Augeas tree:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><a href="https://github.com/hercules-team/augeas/wiki/Adding-nodes-to-the-tree">https://github.com/hercules-team/augeas/wiki/Adding-nodes-to-the-tree</a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>There is just one very useful short-cut, which is not mentioned on the wiki: Augeas will create any node you are about to use automatically, in case it doesn't exist.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>> 1) creating 'tags' if not present<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>set $datadog/tags<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>… will create a 'tags' node (in last position) on root level if it doesn't exist yet, otherwise nothing will happen. ($datadog contains the path to your datadog.ini file)<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>> 2) checking the tag string for the presence of my key:value pair<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Use 'print' or 'match' with a suitable xpath expression.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>> 3) appending my key:value pair tag if not present<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>set $datadog/tags/<key> <value><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>(Replace key and value with your strings) This will create a node with your key or update the existing node and assign it the value. This works as long as the key-string is unique.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Ciao,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Xavier.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=DE style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=DE style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> augeas-devel-bounces@redhat.com [mailto:augeas-devel-bounces@redhat.com] <b>On Behalf Of </b>Nathan Valentine<br><b>Sent:</b> Friday, March 04, 2016 7:58 PM<br><b>To:</b> augeas-devel@redhat.com<br><b>Subject:</b> [augeas-devel] lens and query to append to a key:value pair in an INI file<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>Hey, folks.<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Not sure if I'm stuck on a problem with my custom lens, my understanding of XPATH queries, or both (likely).<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I'm trying to write a lens for the Datadog monitoring agent config file which is an INI file using ':' as the separator. I took the Puppet.lens and modified it ever so lightly. Here's a link for reference:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal><a href="https://github.com/nrvale0/puppet-datadog-agent/blob/add_tag_define/lib/augeas/lenses/datadogagent.aug">https://github.com/nrvale0/puppet-datadog-agent/blob/add_tag_define/lib/augeas/lenses/datadogagent.aug</a><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>And here's a snippet of a typical datadog.conf file:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><a href="https://gist.github.com/nrvale0/6fe12c3bcf7777340455">https://gist.github.com/nrvale0/6fe12c3bcf7777340455</a><o:p></o:p></p></div></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>The motivation for writing the lens is I would like to be able to append new tags to /files/etc/dd-agent/datadog.conf/Main/tags but I'm unsure as to the best/correct way of:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>1) creating 'tags' if not present<o:p></o:p></p></div><div><p class=MsoNormal>2) checking the tag string for the presence of my key:value pair<o:p></o:p></p></div><div><p class=MsoNormal>3) appending my key:value pair tag if not present<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I'm also a little concerned that there will be a parse conflict with the INI file format of using colon as a delimeter and the values of the 'tags' entry having embedded colons but first things first..<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Any advice would be greatly appreciated.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div><p class=MsoNormal>-- <o:p></o:p></p><div><div><p class=MsoNormal>--- V<o:p></o:p></p></div></div></div></div></div></body></html>