How to convert document in to Base64 in Appian 18.1 to send this base64 string to other system via their REST API

How to convert document in to Base64 in Appian 18.1 to send this base64 string to other system via their REST API

Please note we have 18.1, We want to upload document via Appian, Currently we able to upload it & store document in KC. But unable to convert to Base64 to send to other REST API.

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