First, the background: I'm writing a Ruby app that uses SendGrid to send mass emails. SendGrid uses a custom email header (in JSON format) to set recipients, values to substitute, etc. SendGrid's documentation recommends splitting up the header so that the lines are shorter than 1,000 bytes.
My question, then, is this: given a long JSON string, how can I split it into lines < 1,000 so that lines are split at appropriate places (i.e., after a comma) rather than in the middle of a word?
This is probably unnecessary, but here's an example of the sort of string I'd like to split:
X-SMTPAPI: {"sub": {"pet": ["dog", "cat"]}, "to": ["test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com", "test@gmail.com", "anothertest@gmail.com"]}
Thanks in advance for any help you can provide!