Extract From JSON (ssGTM)

Custom Variable Template for Server-Side Google Tag Manager

Extract element from JSON object or valid JSON string by path using dot-notation

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Usage

Create a new variable with this template. Choose a variable as input that holds an array or JSON object like "items" from event data or an extracted JSON string (see notes below) from a request parameter. Then define a path to the desired element / property using dot-notation.

The variable will parse the input (if neccessary) and query the defined path. returns the value of the element. If the result is an object, if can be stringified.

Example

If the input consists of the following object or the corresponding JSON string:

{
  something: 42,
  some_object: {key1: 'value1', key2: 'value2', key3: 'value3'},
  items: [
    {itemName: 'example item 1', itemPrice: 199},
    {itemName: 'example item 2', itemPrice: 321.5},
  ]
}

... then the following paths will fetch these values:

Path	Value
something	42
some_object.key3	value3
items[1].itemPrice	321.5
some_object	{key1: 'value1', key2: 'value2', key3: 'value3'} (optionally as a string)

Querying an array with this template can be done by starting the path with an index. "[0]" as a path returns the first element; [0].price the "price" element in an object in the first element of an array.

Using string inputs

If you send an object as a serialized JSON string, make sure to use a valid format. The example object above would only be valid, if it is contained in a string value like this:

{"something":42,"some_object":{"key1":"value1","key2":"value2","key3":"value3"},"items":[{"itemName":"example item 1","itemPrice":199},{"itemName":"example item 2","itemPrice":321.5}]}

Make sure to only use " as a string delimiter for all string values and key names! The following strings cannot be parsed and so you would not get the desired results:

//This will not work because the wrong delimiter was used:
{'something':42,'some_object':{'key1':'value1','key2':'value2','key3':'value3'},'items':[{'itemName':'example item 1','itemPrice':199},{'itemName':'example item 2','itemPrice':321.5}]}

//This is also wrong because key names do not have demimiters:
{something:42,some_object:{key1:"value1",key2:"value2",key3:"value3"},items:[{itemName:"example item 1",itemPrice:199},{itemName:"example item 2",itemPrice:321.5}]}

Tip: Take a sample of your raw field values you want to parse and try to convert it to an object in your browser's console using JSON.parse().