Editing a XML file with xmlstarlet-CodePudding

I want to change a value in a XML file from shell. I have tried xmlstarlet and I tried different codes but it did not work.

What I have tried / used:

xmlstarlet ed --ps --inplace --update 'core/databus/*/key[@name="SystemName"]/value[@type]/type' -v "test" template.xml.

xmlstarlet ed -u core/databus/key_value_mappings/key[@name="SystemName"]/value[@type="value"]/@value -v "test" template.xml.

Problem:

When I used these codes nothing changed.

What I would like:

I would like to change the value SystemName. Technodrome to test123 for example.

xml file

<core>
    <template>
        <!-- General information about the template -->
        <entity name="unit">S7-200</entity>
        <entity name="vendor">Siemens</entity>
        <entity name="description">Rough simulation of a basic Siemens S7-200 CPU with 2 slaves</entity>
        <entity name="protocols">HTTP, MODBUS, s7comm, SNMP</entity>
        <entity name="creator">the conpot team</entity>
    </template>
    <databus>
        <!-- Core value that can be retrieved from the databus by key -->
        <key_value_mappings>
            <key name="FacilityName">
                <value type="value">"Mouser Factory"</value>
            </key>
            <key name="SystemName">
                <value type="value">"Technodrome"</value>
            </key>
            <key name="SystemDescription">
                <value type="value">"Siemens, SIMATIC, S7-200"</value>
            </key>
            <key name="Uptime">
                <value type="function">conpot.emulators.misc.uptime.Uptime</value>
            </key>
            <key name="sysObjectID">
                <value type="value">"0.0"</value>
            </key>
            <key name="sysContact">
                <value type="value">"Siemens AG"</value>
            </key>
            <key name="sysName">
                <value type="value">"CP 443-1 EX40"</value>
            </key>
            <key name="sysLocation">
                <value type="value">"Venus"</value>
            </key>
            <key name="sysServices">
                <value type="value">"72"</value>
            </key>
            <key name="memoryModbusSlave0BlockA">
                <value type="value">[random.randint(0,1) for b in range(0,128)]</value>
            </key>
            <key name="memoryModbusSlave0BlockB">
                <value type="value">[random.randint(0,1) for b in range(0,32)]</value>
            </key>
            <key name="memoryModbusSlave255BlockA">
                <value type="value">[random.randint(0,1) for b in range(0,128)]</value>
            </key>
            <key name="memoryModbusSlave255BlockB">
                <value type="value">[random.randint(0,1) for b in range(0,32)]</value>
            </key>
            <key name="memoryModbusSlave1BlockA">
                <value type="value">[random.randint(0,1) for b in range(0,128)]</value>
            </key>
            <key name="memoryModbusSlave1BlockB">
                <value type="value">[random.randint(0,1) for b in range(0,32)]</value>
            </key>
            <key name="memoryModbusSlave2BlockC">
                <value type="value">[random.randint(0,1) for b in range(0,8)]</value>
            </key>
            <key name="memoryModbusSlave2BlockD">
                <value type="value">[0 for b in range(0,32)]</value>
            </key>
            <key name="Copyright">
                <value type="value">"Original Siemens Equipment"</value>
            </key>
            <key name="s7_id">
                <value type="value">"88111222"</value>
            </key>
            <key name="s7_module_type">
                <value type="value">"IM151-8 PN/DP CPU"</value>
            </key>
            <key name="empty">
                <value type="value">""</value>
            </key>
        </key_value_mappings>
    </databus>
</core>

CodePudding user response：

Take the first XPath expression, you tried: it leads to an element name type which is child of an element value having an attribute type. Such an element does not exist, so nothing can be updated.

Try

xmlstarlet ed --ps -u 'core/databus/*/key[@name="SystemName"]/value' -v "test" template.xml

instead