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hpr3394 :: Be an XML star with xmlstarlet

Parse XML from the terminal

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Hosted by klaatu on 2021-08-05 is flagged as Clean and is released under a CC-BY-SA license.
Tags: xml,data,markup,markdown.
Listen in ogg, spx, or mp3 format. | Comments (1)

See the layout of an XML document


$ xmlstarlet elements planets.xml
xml
xml/sol
xml/sol/planet
xml/sol/planet/name
xml/sol/planet/albedo
xml/sol/planet
xml/sol/planet/name
xml/sol/planet/albedo
xml/sol/planet
xml/sol/planet/name
xml/sol/planet/albedo

See content of the planet node


$ xmlstarlet select -t --value-of '/xml/sol/planet' planets.xml

        Mercury
        0.11

        Venus
        0.7

        Terra
        0.39

Get the third instance of the planet node


$ xmlstarlet select -t --value-of '/xml/sol/planet[3]' planets.xml
Terra
0.39

Get only the planets with an albedo greater than 0.25


$ xmlstarlet select -t --value-of '/xml/sol/planet[albedo > 0.25]' planets.xml

Venus
0.7

Terra
0.39

Get only the planets closer to Sol than the third planet


$ xmlstarlet select -t --value-of '/xml/sol/planet[position() < 3]' planets.xml

Mercury
0.11

Venus
0.7

Learn more XPath functions at Mozilla Developer Network.

Download xmlstarlet from xmlstar.sourceforge.net (https://sourceforge.net/projects/xmlstar/).


Comments

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Comment #1 posted on 2021-08-05T14:54:19Z by norrist

My one cool xmlstarlet trick

I had to install an xml config file on a bunch of servers.
The xml was the same for every server except the hostname had to be added to a specific field.

My first thought was to use sed, but anyone who has tried parsing xml with regex knows just how far I got.

Searching for something like sed that understood xml tags led me to xmlstarlet.
Here is the command I used to add the hostname of the server to the xml path "info/host-id":

xmlstarlet ed --inplace -u info/host-id -v `hostname -f` /path/to/info.xml

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