Getting values from a hash using a path string

Anyone else who builds functional blocks in for instance webhooks?

As I’m creating a lot of webhooks that I use as functional blocks, I tend to pass around a lot of JSON. One of the implications is that want to retrieve values from these JSON hashes using variable paths.

This little function has helped me a lot there:

<#function getValueFromPath source={} path="">
    <#assign parts = path?split(".")>
    <#assign current = source>
    <#list parts as p>
        <#if p?matches(".*\\[\\d+\\]")>
            <#assign key = p?replace("\\[\\d+\\]", "", "r")>
            <#assign idx = p?replace(".*\\[(\\d+)\\]", "$1", "r")?number>
            <#assign current = current[key][idx]!>
        <#else>
            <#assign current = current[p]!>
        </#if>
    </#list>
    <#return current>
</#function>

There’s a multitude of ways to use this.

One method I use a lot is to send an incoming body to my ‘Update Asset’ webhook which holds a body like below, where I pass the asset id, the fields to update and the paths where to find the values, and the source so search in which gives me a small reusable piece of functionality.

The status value I use for setting my status field afterwards to help other processes to identify if a step in a specific workflow has been tackles successfully.

{
    "assetId": "a83f3e97-5db2-42be-a989-8e5a5c8ff2be",
    "status": "ST-03-02",
    "paths": {
        "width": "dimensions.width",
        "height": "dimensions.height",
        "firstRating": "reviews[0].rating"
    },
    "source": {
        "id": 1,
        "title": "Essence Mascara Lash Princess",
        "description": "The Essence Mascara Lash Princess is a popular mascara known for its volumizing and lengthening effects. Achieve dramatic lashes with this long-lasting and cruelty-free formula.",
        "category": "beauty",
        "price": 9.99,
        "discountPercentage": 7.17,
        "rating": 4.94,
        "stock": 5,
        "tags": [
            "beauty",
            "mascara"
        ],
        "brand": "Essence",
        "sku": "RCH45Q1A",
        "weight": 2,
        "dimensions": {
            "width": 23.17,
            "height": 14.43,
            "depth": 28.01
        },
        "warrantyInformation": "1 month warranty",
        "shippingInformation": "Ships in 1 month",
        "availabilityStatus": "Low Stock",
        "reviews": [
            {
                "rating": 2,
                "comment": "Very unhappy with my purchase!",
                "date": "2024-05-23T08:56:21.618Z",
                "reviewerName": "John Doe",
                "reviewerEmail": "john.doe@x.dummyjson.com"
            },
            {
                "rating": 2,
                "comment": "Not as described!",
                "date": "2024-05-23T08:56:21.618Z",
                "reviewerName": "Nolan Gonzalez",
                "reviewerEmail": "nolan.gonzalez@x.dummyjson.com"
            },
            {
                "rating": 5,
                "comment": "Very satisfied!",
                "date": "2024-05-23T08:56:21.618Z",
                "reviewerName": "Scarlett Wright",
                "reviewerEmail": "scarlett.wright@x.dummyjson.com"
            }
        ],
        "returnPolicy": "30 days return policy",
        "minimumOrderQuantity": 24,
        "meta": {
            "createdAt": "2024-05-23T08:56:21.618Z",
            "updatedAt": "2024-05-23T08:56:21.618Z",
            "barcode": "9164035109868",
            "qrCode": "..."
        },
        "thumbnail": "...",
        "images": [
            "...",
            "...",
            "..."
        ]
    }
}