If you are new to web service interfaces, first review HTTP Request Structure for an overview of what makes up an HTTP request.
Tips:
use Custom Fields for configurations - avoid hardcoding.
url, authentication data (clientID, client secrets, username, password, tokens, etc.)
pass parameters as a table
pcall(), Retry Library, log errors
Prepping the body:
json.serialize
tostring() or S()
urlcode.encodeTable - lua table to query string
SSL certificates in net.http.* - Enable TLS/SSL with the Network Client APIs
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