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xmllinuxxmlstarlet

How do I update <path> in my XML according to the given file name

<annotation>
  <folder>cars_train</folder>
  <filename>00001.jpg</filename>
  <path>Users/hantaoliu/Documents/Research/cars_train/.jpg</path>
  <source>
    <database>Unknown</database>
  </source>
  <size>

The text above is one of the XML file I want to update. I have 7k XML files and I want the path of them to be:

Users/hantaoliu/Documents/Research/cars_train/$@.jpg

$@ corresponds to the name of the input file. For example, if the input file is 00001.xml, I want the path to be: 

Users/hantaoliu/Documents/Research/cars_train/00001.jpg

I'm using xmlstarlet, but I'm not able to figure it out?

Solution

  • You can accomplish what you want like so. First select the value of filename and the value of path.

    $ filenameVal=$(xmlstarlet sel -t -v "/annotation/filename" file)
$ pathVal=$(xmlstarlet sel -t -v "/annotation/path" file)

    Next determine the directory name of path via the $(dirname $pathVal) and concatenate $filenameVal to it. You can do a test run of this without editing the file like so:

    $ xmlstarlet ed -u "/annotation/path" -v "$(dirname $pathVal)/$filenameVal" file
<?xml version="1.0"?>
<annotation>
  <folder>cars_train</folder>
  <filename>00001.jpg</filename>
  <path>Users/hantaoliu/Documents/Research/cars_train/00001.jpg</path>
  <source>
    <database>Unknown</database>
  </source>
  <size>
  </size>
</annotation>

    If things look good you can add the -L switch which tells xmlstartlet to edit in place.

    $ xmlstarlet ed -L -u "/annotation/path" -v "$(dirname $pathVal)/$filenameVal" file

    Confirming the results in file:

    $ cat file
<?xml version="1.0"?>
<annotation>
  <folder>cars_train</folder>
  <filename>00001.jpg</filename>
  <path>Users/hantaoliu/Documents/Research/cars_train/00001.jpg</path>
  <source>
    <database>Unknown</database>
  </source>
  <size>
  </size>
</annotation>

    References