User Storage

userStorage API (Server-Side)

The userStorage API is the primary interface for persisting data server-side per tool instance for a specific user. It is commonly used to store identifiers such as:

• Client IDs (e.g., client_id)

• Click IDs (e.g., gclid, fbclid)

• Campaign parameters or session-level values

These functions are available within the server-side variable runtime environment under the this scope.

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Available Functions

1. this.userStorage.write(name, value, expirationTimestamp)

Stores a value under a given key and defines when it should expire.

Parameters

Placeholder	Description	Type	Required	Example
<NAME>	The key used to store and retrieve the value	string		"client_id"
<VALUE>	The value to be stored (can be any data type)	any		"123abcd123.11111111"
<EXPIRATION TIMESTAMP>	Unix timestamp (in milliseconds) for automatic expiration	number (milliseconds)		1740555149453

Example

async function() {
    const href = this.getFrontendVariable('window_location_href');
    const url = new URL(href);
    const gclid = url.searchParams.get("gclid");

    if (gclid) {
        const expirationTime = Date.now() + 7890000000;
        this.userStorage.write("gclid", gclid, expirationTime);
        return gclid;
    }

    return null;
}

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2. this.userStorage.read(name)

Reads a stored value from user storage based on the given key.

Parameters

Placeholder	Description	Type	Required	Example
<NAME>	The key under which the value is stored	string		"gclid"

Example

async function() {
    const gclid = this.userStorage.read("gclid");
    return gclid || "";
}

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3. this.userStorage.delete(name)

Deletes a stored value from user storage by key.

Parameters

Placeholder	Description	Type	Required	Example
<NAME>	The key under which the value is stored	string		"gclid"

Example

async function() {
    this.userStorage.delete("gclid");
    return "";
}

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Best Practices

• Always set a realistic expiration for stored values to prevent unnecessary data buildup.

• Combine client-side values with server-side logic for advanced tracking use cases.

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Summary

The userStorage API enables persistent, scoped storage for identifiers and session-related data inside server-side variables. It offers a simple but powerful interface to write, read, and delete values securely within the JENTIS TWIN-Browser runtime.

For additional guidance or complex implementations, please refer to the Server-Side Variable Guide or contact JENTIS Support.