Question

4

Generate Tree Output from Specific/General XML file in Bash

rated 0 times [ 4] [ 0] / answers: 1 / hits: 3144 / 2 Years ago, tue, august 9, 2022, 2:30:20

I am trying to generate a tree from a XML file in Bash.

This is a part of the XML file:

  <menu name="main_menu" display="Main Menu">

      <application name="load_profiles" display="Load Profile"/>

      <application name="save_profiles" display="Save Profile"/>

      <application name="remove_profiles" display="Delete Profile"/>

      </menu>

I have tried to use CAT and GREP and AWK:

cat menu.xml | grep menu name | awk -v FS="(display="|" help)" '{print $2}' > menulist.txt

I have first GREPed using the lines that has "Menu Name" and then printed the Tests between 'display="' and '" help' and came out with this output:

Main Menu">

Broadband

Load and Save Profiles

xDSL Interface

But what I want is to Grep all the lines that has "Menu Name", "parameter type", "application name" and "value id" and print their display name in a tree like output. I am not sure how I can Grep multiple values from multiple lines and print specific string from it.

Then I have seen that it is comparatively easier to do this with a XML parser tool. So I have tried with XMLStarlet:

xmlstarlet el menu.xml|awk -F'/' 'BEGIN{print "digraph{"}{print $(NF-1)" -> "$NF}END{print"}"}'> menumenutxt.txt

Using this command I have found the following output:

menu -> menu

menu -> onenter

menu -> menu

menu -> application

menu -> application

menu -> application

menu -> parameter

parameter -> value

parameter -> value

Which definitely looks better and closer to what I want. But it's not printing the display name.

What I am trying to print is something like this:

 Main Menu -> 

           -> Broadband 

                        -> Load and Save Profiles

                                                  -> Load Profile

                                                  -> Save Profile

                                                  -> Delete Profile

Or the following:

Main Menu 

-> Broadband 

--> Load and Save Profiles

---> Load Profile

---> Save Profile

---> Delete Profile

My aim to to get an output as close to it as possible. Can anyone suggest me how I should proceed with this?

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piscen

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3 Years ago

answered 2 Years ago algicuade · Accepted Answer

Adapting one of the examples from the xmlstarlet docs:

xmlstarlet sel -T -t -m '//*' 

    -i '@display' 

        -m 'ancestor-or-self::*' 

            -i '(position()=last())' 

                -o '-> ' -v '@display' -b 

            -o $'	' -b 

        -n foo.xml

The example is:

Print structure of XML element using xml sel (advanced XPath
expressions and xml sel command usage)
xml sel -T -t -m '//*' 

-m 'ancestor-or-self::*' -v 'name()' -i 'not(position()=last())' -o . -b -b -n 

xml/structure.xml
Result Output:
a1

a1.a11

a1.a11.a111

a1.a11.a111.a1111

a1.a11.a112

a1.a11.a112.a1121

a1.a12

a1.a13

a1.a13.a131

From here, the things we need to modify are:

print the display attribute instead of the name, so @display instead of name()

print it only for the last element. We already have the test for printing . for all but the last element, so it's easy to invert that.

print tabs to indent (we can do it after every element, it will just leave trailing, invisible tab), so just -o $' '. $' ' in bash will get you a tab character.

print only for elements which have the display attribute, so -i '@display'

I have indented the command above to make the flow clearer.

The output I get:

$ xmlstarlet sel -T -t -m '//*' -i '@display' -m 'ancestor-or-self::*' -i '(position()=last())' -o '-> ' -v '@display' -b -o $'	' -b -n foo.xml

-> English

    -> Main Menu

        -> Broadband

            -> Load and Save Profiles

                -> Load Profile

                -> Save Profile

                -> Delete Profile

            -> Interface

                -> xDSL

                -> SFP

                -> Ethernet

                -> SHDSL

            -> xDSL Interface

                -> xDSL Mode

                    -> Annex A/M

                    -> Annex B/J

                -> MAC Address

                    -> MAC Address

                -> Vectoring Mode

                    -> Disabled

                    -> Enabled

                    -> Friendly

                -> G.FAST

                    -> Disabled

                    -> Enabled

After thinking a bit, the following is simpler:

xmlstarlet sel -T -t -m '//*' 

    -i '@display' 

        -m 'ancestor::*' 

            -o $'	' -b 

        -o '-> ' -v '@display' -n foo.xml

Using ancestor::* instead of ancestor-or-self::* makes printing the tabs correctly easier, and eliminates the extra test for last element.

Similar output, but without trailing tabs:

-> English

    -> Main Menu

        -> Broadband

            -> Load and Save Profiles

                -> Load Profile

                -> Save Profile

                -> Delete Profile

            -> Interface

                -> xDSL

                -> SFP

                -> Ethernet

                -> SHDSL

            -> xDSL Interface

                -> xDSL Mode

                    -> Annex A/M

                    -> Annex B/J

                -> MAC Address

                    -> MAC Address

                -> Vectoring Mode

                    -> Disabled

                    -> Enabled

                    -> Friendly

                -> G.FAST

                    -> Disabled

                    -> Enabled