Attribute: when - evolv-ai/metrics GitHub Wiki

The when attribute provides a mechanism to activate a metric or set of metrics conditionally. The when clause must be satisfied bofore the current metric or any of its decendants are applied.

It supports the following value types:

• string: Is used as regex to apply to a value of type string
• number: Is used for an exact match on a value of type number
• boolean: Is used for an exact match on a value of type boolean
• object: Is used to provide a match on a value of type number with following options:
  • {"operator": "<", "value": 10}: matches on values less than 10
  • {"operator": "<=", "value": 10}: matches on values less than or equal to 10
  • {"operator": ">", "value": 10}: matches on values greater than 10
  • {"operator": ">=", "value": 10}: matches on values greater or equal to 10

The when attribute can appear in metrics nested in apply or map arrays.

Example

In apply

{
    "source": "expression",
    "key": "window.location.pathname",
    "action": "event",
    "apply": [
        {
            "when": "^(/product)$",
            "tag": "page-load.product"
        },        
        {
            "when": "^(/purchase)$",
            "tag": "page-load.purchase"
        }
    ]
}

In map

{
    "source": "expression",
    "key": "document.referrer",
    "type": "string",
    "tag": "referrer.searchEngine",
    "map": [
        {"when": "google.com",     "value": "google"},
        {"when": "bing.com",       "value": "bing"},
        {"when": "search.yahoo",   "value": "yahoo"},
        {"when": "yandex.com",     "value": "yandex"},
        {"when": "duckduckgo.com", "value": "duckduckgo"}
    ]
}

For numeric

{           
    "source": "dom"     
    "key": "form select.amount",
    "type": "number",
    "on": "change",
    "extract": {
        "attribute": "value",
        "parse": "[0-9,]+.?$"
    },
    "apply": [
        {"tag": "request.amount", "action": "bind" },
        {"tag": "below-ten.requested", "action": "event",  "when" : {"operator": "<", "value": 10000}},
        {"tag": "above-ten.requested", "action": "event", "when" : {"operator": ">=", "value": 10000}}
    ]
}