在具有命名空间的Xpath表达式中循环

Question

Suppose this my Sample XML with Namespaces

<data>
    <vnfr:vnfr-catalog xmlns:vnfr="urn:ietf:params:xml:ns:yang:nfvo:vnfr">
        <vnfr:vnfr>
            <vnfr:id>1234</vnfr:id>
                <vnfr:vdur>
                    <vnfr:id>987</vnfr:id>
                    <vnfr:id>987</vnfr:id>
                    <vnfr:management-ip>10.100.100.10</vnfr:management-ip>
                </vnfr:vdur>
                <vnfr:vdur>
                    <vnfr:id>567</vnfr:id>
                    <vnfr:id>567</vnfr:id>
                    <vnfr:management-ip>10.100.100.11</vnfr:management-ip>
                </vnfr:vdur>
        </vnfr:vnfr>
    </vnfr:vnfr-catalog>
</data>

I have a sample Xpath expression which I use in Java

expression="/data/*[local-name() = 'vnfr-catalog']/*[local-name() = 'vnfr']/*[local-name() = 'id']/*[local-name() = 'vdur']/*[local-name() = 'management-ip']/text()";

Output: 10.100.100.10

But how to Iterate and fetch the 2nd management-ip ie 10.100.100.11

I tried the below expression with vdur[2] , but it didn't worked.

expression="/data/*[local-name() = 'vnfr-catalog']/*[local-name() = 'vnfr']/*[local-name() = 'id']/*[local-name() = 'vdur[2]']/*[local-name() = 'management-ip']/text()";

How to fetch the 2nd management IP using expression??????

Answer 1

Your query has two mistakes:

1. You should not get into id element since it does not contain management-ip , they are on the same level of hierarchy
2. *[local-name() = 'vdur[2]'] should be replaced with *[local-name() = 'vdur'][2]

Below is my query that seems working:

/data/vnfr:vnfr-catalog/vnfr:vnfr/vnfr:vdur[2]/vnfr:management-ip/text()

This is tested on

<data xmlns:vnfr="asdasdas">
    <vnfr:vnfr-catalog>
        <vnfr:vnfr>
            <vnfr:id>1234</vnfr:id>
                <vnfr:vdur>
                    <vnfr:id>987</vnfr:id>
                    <vnfr:id>987</vnfr:id>
                    <vnfr:management-ip>10.100.100.10</vnfr:management-ip>
                </vnfr:vdur>
                <vnfr:vdur>
                    <vnfr:id>567</vnfr:id>
                    <vnfr:id>567</vnfr:id>
                    <vnfr:management-ip>10.100.100.11</vnfr:management-ip>
                </vnfr:vdur>
        </vnfr:vnfr>
    </vnfr:vnfr-catalog>
</data>

Above is your example but amended a bit since you are not declaring the namespace.

Output:

Text='10.100.100.11'

Tested in https://www.freeformatter.com/xpath-tester.html

Your correct query would look like this:

/data/*[local-name() = 'vnfr-catalog']/*[local-name() = 'vnfr']/*[local-name() = 'vdur'][2]/*[local-name() = 'management-ip']/text()

Answer 2

As Alexey resolve your one issue. below is the answer to getting the length of an attribute

While xxx is the tag prefix, use just count(//Formulas/yyy)

Use count keyword

Source

count of element in XPath

Hope it will help you :)