Text Values for Events

Right so I have an implementation on my side where we need to collect the application attribute details which sometimes can be over 20 at a time. I have the same restriction as you where I should only use minimum amount of variables, in my case one.

The best solution is to use an eVar as you can set up to 250char, we will put a concatenated value of key=value pairs delimited by a pipe "|". Each key will be an ID instead of the full name to limit the char usage. I then use Classification rule builder using Regex to split each key/pair values into their own reports. I can also create calculated metrics based on the values to get the individual metrics.

Also as it seems you have modals then you would use s.tl instead of s.t call so we will provide a custom name for each interaction in s.tl which result in new line item in the custom link report.

So lets say per your example we want to track type of component (i.e modal or page asset), type of interaction, etc..

s.eVarX = "loc=modal|ev=CLICK|item=BUTTON|value=myvalue123"

What we want is to create dynamic values so if a key does not have a value we do not want to put, use this code to achieve this:

Data Element code: 

/**
 * The mapping value can either be a function, hard co
 */
function builKeyValue(key, config) {
    try {
        var value = '';

        if (!config[key]) {
            return '';
        }
        //get value
        if (typeof config[key] == 'function') {
            value = config[key]();
        } else {
            value = _satellite.getVar(config[key]);
        }

        //transform value    
        if (typeof value == 'boolean') {
            value = value ? 1 : 0;
        }

        if (value instanceof Array && value.length > 0) {
            value = value.toString();
        }
        return value ? key + '=' + value + '|' : '';
    } catch (e) {
        _satellite.logger.error('[Build string from map] Failed to build key/value for key ', key);
        return '';
    }
}

function buildStringFromMap(config) {
    try {
        var output = '';

        for (var key in config) {
            output += builKeyValue(key, config)
        }

        return output;
    } catch (e) {
        _satellite.logger.error('Failed to build string from map -- ', e);
    }
}

var mapping = {
    "loc": "componentDataElement",
    "ev": "eventDataElement",
    "item": "itemDataElement",
    "value": "valueDataElement"
}

return buildStringFromMap(mapping);

For the rule builder create the classification in advance and then in the classification rule builder create a rule based on regex:

Rule type: Regular expression

Match criteria: ^.*loc=([^\|]+)\|.*$

Classification: Select the target classification report name

To: $1

Hope this helps