extractSearchParams — GTM Variable Template for URL

VARIABLES › URL

extractSearchParams CORE URL

Direct (.tpl) Apply (.tpl) Add to GTM

Extracts query parameters from a URL as key-value pairs or a specific parameter.

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When to Use This

URL Processing

Parse, build, decode, and manipulate URLs and query parameters.

Extraction

Pull specific values, segments, or patterns from complex data structures.

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Examples

Extract all parameters

INPUT

URL: https://example.com?foo=bar&baz=qux
Parameter Key: undefined

OUTPUT

{foo: 'bar', baz: 'qux'}

Extract specific parameter

INPUT

URL: https://example.com?foo=bar&baz=qux
Parameter Key: foo

OUTPUT

bar

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GTM Configuration

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Read-only Preview

extractSearchParams

URL

💾 The URL to extract the search parameters from.

Supported formats:
  ✓ String

Extract Specific Parameter

Parameter Key

💾 The specific query parameter key to extract (e.g., 'utm_source', 'id'). If provided, returns only the value of this parameter instead of the entire object.

Supported formats:
  ✓ String

*** Extract all parameters***

*** Extract specific parameter***

Input Setup

Input Function (optional)

⚙️ Optional pre-processing function applied to the URL before internal logic (e.g., normalize URL format, add base domain). Internal transformations will still apply afterward.

Result Handling

Output Function (optional)

⚙️ Optional function to apply to the result before returning it (e.g., value => value.toUpperCase() for string values, params => Object.keys(params).length to count parameters). Useful for chaining transformations on the output.

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Related Variables

Same category: URL

→ assignParamsToString → buildUrlFromParts → completeUrl → decodeUri → decodeUriComponent → encodeURIComponent → encodeUri → extractHash → extractHashParams → extractHost → extractHostname → extractOrigin → extractPasword → extractPathname → extractPort → extractProtocol → extractSearch → extractSegmentByIndex → extractUserName → hasFragment → hasParameterWithValue → hasQueryString → omitParamsFromString → parseUrlComponents → pickParamsFromString → stringToPath → ⚡ URL › Transformer

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Under the Hood

📜 View Implementation Code

/**
 * Extracts the searchParams from a given URL, optionally filtering for a specific parameter.
 *
 * @param {string} data.src - The URL to extract the searchParams from.
 * @param {string} [data.key] - Optional specific query parameter key to extract.
 * @param {Function|string} [data.out] - Optional output handler: function to transform result or string with format.
 *
 * Direct-mode specific parameters:
 * @param {Function} [data.pre] - Optional pre-processor function to transform src before extracting.
 *
 * @returns {Object<string, (string|Array)>|string|Array|undefined} The searchParams object, specific parameter value, or undefined if invalid.
 *
 * @framework ggLowCodeGTMKit
 */
const parseUrl = require('parseUrl');
const extractSearchParams = function(url, key) {
    const parsed = parseUrl(url);
    if (!parsed || !parsed.searchParams) {
        return undefined;
    }
    if (key !== undefined && key !== null && key !== '') {
        return parsed.searchParams[key];
    }
    return parsed.searchParams;
};
const safeFunction = fn => typeof fn === 'function' ? fn : x => x;
const out = safeFunction(data.out);
// ===============================================================================
// extractSearchParams - Direct mode
// ===============================================================================
const applyCast = (castFn, value) => safeFunction(castFn)(value);
const value = applyCast(data.pre, data.src);
return out(extractSearchParams(value, data.key));
// ===============================================================================
// extractSearchParams(...) – Apply Mode
// ===============================================================================
/*
return function(value, key) {
  key = data.rp1 ? key : data.key;
  return out(extractSearchParams(value, key));
};
*/

🧪 View Test Scenarios (8 tests)

✅ '[example] Extract all parameters'
✅ '[example] Extract specific parameter'
✅ Extract non-existent parameter
✅ URL without search parameters
✅ Extract parameter with duplicate values (array)
✅ Invalid URL
✅ Empty key parameter (should return all params)
✅ UI-bound mode with static key