Using Linux Bash Script to get data from XML file

Question

I have a XML files with data in it that I need to extract with a Linux Bash Script. For example, I need everything in the brackets and to print out in terminal accordingly (first name in next to first description).

What is the best way to do this? I was able to do it with c# using XPath, but I can't do that simply using a Linux Bash Script correct? I know I can get most of it done with awk, sed, grep, cut ect, but I don't think (actually I know I am not) doing it properly. I am at a point were I extracted description data to a file and name to a file, but after a few hours, I realized this is not the best/proper way.

Example of how it should read is.

name1 - description1
name2 - description2
name3 - (blank)
name4 - description3

Thank you!

If I can add any detail to make it clearer, please let me know! (Brain is a little fried from a long day at work)

Sample XML (simplified it down to one instance)

<zabbix_export>
<templates>
    <template>
        <items>
            <item>
                <name>Available memory</name>
                <description>Available memory is defined as free+cached+buffers memory.</description>                  
            </item>
        </items>
    </template>
<templates>

How it should read out:

<name>Available memory</name> - <description>Available memory is defined as free+cached+buffers memory.</description>
<name>Another Name</name> - <description>Another Description</description>
<name>Another Name</name> - <description>Another Description</description>
<name>Another Name</name> - <description>Another Description</description>

Sample XML data would be useful – Mark O'Connor Jun 25 '12 at 21:43 — Mark O'Connor, Jun 25 '12 at 21:43
Added a simplified example of the XML – PolarisUser Jun 25 '12 at 21:47 — PolarisUser, Jun 25 '12 at 21:47

score 3 · Answer 1 · answered Jun 25 '12 at 22:00

3

command

xmlstarlet sel -t -m '//item/*' -c . -n input.xml |
    sed '2~2s/$/\n/' |
        awk -F'\n' -vRS='' '{print $1" - "$2}'

output

<name>Available memory</name> - <description>Available memory is defined as free+cached+buffers memory.</description>
<name>Available memory</name> - <description>Available memory is defined as free+cached+buffers memory.</description>
<name>Available memory</name> - <description>Available memory is defined as free+cached+buffers memory.</description>

answered Jun 25 '12 at 22:00

kev

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So, almost there!!! I got that to work properly, but some of my descriptions in my XML file are blank. Is there a way for it to skip the blank descriptions so it displays properly? – PolarisUser Jun 25 '12 at 22:35

score 2 · Accepted Answer · answered Jun 25 '12 at 21:49

2

You can launch an xpath command from bash. It installs with Perl XML and allows you to do any XPath queries to stdout very comfortably.

answered Jun 25 '12 at 21:49

Jirka Hanika

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Well, I have been trying to get it to work in Perl doing it that way, but I can't seem to get it to work (never used Perl before). I know it is possible to get it to print like this just using Bash Script. – PolarisUser Jun 25 '12 at 21:50
I really only want to use Linux Bash Script commands (not Perl or anything) – PolarisUser Jun 25 '12 at 21:52
@PolarisUser - and you really get right that. `xpath` is a command line utility that you run directly from Bash. You only need to know in which package to find it in case that it is not pre-installed on your system which would be a surprise for me. – Jirka Hanika Jun 25 '12 at 21:55
Okay, well I am at the point where I have all the data using XPath with Perl, but I can't seem to format it properly, like I posted :( – PolarisUser Jun 25 '12 at 21:57
1

@PolarisUser - You can follow this previous question (answer) and come back if you run in any other trouble: http://stackoverflow.com/questions/5629091/format-and-combine-output-of-xpath-in-bash – Jirka Hanika Jun 25 '12 at 22:04

score 0 · Answer 3 · answered Jun 25 '12 at 23:17

0

If the xpath executable is not installed, you can install it like so:

cpan XML::XPath

That should download the necessary Perl module, and install the xpath binary.

answered Jun 25 '12 at 23:17

Brian Minton

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Using Linux Bash Script to get data from XML file

3 Answers3

command

output