Item Property Copy

Valve for copying item properties. The operation is performed on one item at a time and does not support copying between items.

Use item_include_expr to control which items are processed (see Item).

Configuration

Valve name: ItemPropertyCopy

Properties

Name	Description	Default value	Mandatory	Expanded
src	Property to copy from.
dest	Property to copy to.
replace	Replace destination. If true existing value of dest will be replaced with new values (overwritten), otherwise new values will be added.	false
filter	Include value predicate. Expression controlling if a value should be copied or not. If not specified, all values are copied. For more information see below.

Example

{
    "name":"ItemPropertyCopy",
    "config":{
        "item_include_expr": "item.id.startsWith('tmp_')",
        "src": "from",
        "dest": "to",
        "replace": false,
        "filter": "value !== ''"
    }
}

Include value predicate

Predicate expression that determines whether a value should be copied. The expression is written in JavaScript and must return true (to copy the value) or false (to skip it).

Scopes

The following scopes are available:

Name	Description	Example
value	The current value	"value.startsWith('__')"
item	The current item	"item.id === 'tmp'"
session	The current session	"session.addProp === true"
state	The current pipe state	"state.itemComplete === false"
request	The current pipe (NOT HTTP) request. Contains all parameters sent to the pipe.	"request.username != null"
items	The current set of items	"items.size > 1"
exports	The current exported (from authenticators or other valves) properties	"!exports.done"

Since item properties are multi valued, values must be indexed (item.value[0]) in expressions or use functions from the mv extension library (mv.contains(item.value, 'value')).