We want to read XML attributes from an XML file. Example of file content is as below:
<properties>
<property name="abc" value="15"/>
<property name="xyz" value="26"/>
</properties>
We want to read value (i.e. 15) for property "abc" using shell script.
Please suggest shell commands to achieve this.
You can use a proper XML parser like xmllint. If your version supports xpath, it will be very easy to grab specific values. If it doesn't support xpath, then you can use --shell option like so:
$ echo 'cat //properties/property[@name="abc"]/@value' | xmllint --shell myxml
/ > -------
value="15"
/ >
You can then use awk or sed to format and extract desired field from output.
$ echo 'cat //properties/property[@name="abc"]/@value' | xmllint --shell myxmlfile | awk -F'[="]' '!/>/{print $(NF-1)}'
15
You can use command substitution to capture the output in a variable by saying:
$ myvar=$(echo 'cat //properties/property[@name="abc"]/@value' | xmllint --shell myxml | awk -F'[="]' '!/>/{print $(NF-1)}')
$ echo "$myvar"
15
Using anything else other than a xmlparser is prone to errors and will break easy.
quick and dirty
sed -n '/<Properties>/,\|</properties>| {
s/ *<property name="xyz" value="\([^"]*\)"\/>/\1/p
}'
no xml check and based on your sample so assume same structure (one property name per line, ...)
posix version (--posix for GNU sed)
sed -n '/<property name="abc"/s/.*value="\(.*\)"[^\n]*/\1/p' file
Creates a hold pattern for the value then matches everything except for the newline to avoid printing the newline, it expects the value double quoted as per your example data.
E.g.
<properties>
<property name="abc" value="15"/>
<property name="xyz" value="26"/>
</properties>
Output:
15
(Prior to edit: sed '/<property name="abc"/s/.*value="\(.*\)"[^\n]*/\1/' file)
func(abc)? or a function that will parse your file and returnabc 15, xyz 26, ...?