add custom attachments on invoices through the REST api (that should be included to the sent invoice to client)

AI generated answer (using internal Slack threads):

Based on the conversations, it seems that you can add custom attachments to invoices through the REST API by using SuiteScript. Here's a general approach: 1. First, you need to upload the file to the NetSuite File Cabinet. This can be done by sending a POST request to the RESTlet and saving the file in the File Cabinet. 2. The file needs to be Base64 encoded and placed somewhere in the JSON request body. This is because files are inconvenient to handle directly, and Base64 encoding allows the file to be handled as text. 3. Once the file is in the File Cabinet, you can attach it to the invoice. This can be done using the

record.attach

method in SuiteScript. Please note that this is a general approach and you might need to adjust it according to your specific needs. Unfortunately, no specific code samples were provided in the conversations. ****** Disclaimer: This response was generated by an artificial intelligence assistant based on previous conversations from multiple Slack channels, and may contain inaccuracies or mistakes. ******