What are the possible values NUR 'error' field?
The error field contains any string value the carrier returns to us and is very carrier/SMSC/UAS/developer dependent
Is the purpose of the messageId solely for the use of the sender?
Yes. Any replies to messages you send out will also include a messageId that will link the reply to your original message.
The ID provided by your service is a string of up to 36 characters. If you are persisting this information to a database, that would be the field type to use.
Can I set the SMS expiration period?
No. Not at this time.
What is the best way to retrieve incoming messages from the eTXT API?
There are two options (Polling and Pushing) to retrieve incoming messages, replies and status updates and it will depend on your network setup, resources and application requirements as to which best suits.
Polling is a client-initiated connection to the eTXT API server and reduces firewall and proxy issues that can occur with the push method. More detail available about polling available here.
The Push option has the eTXT Server connecting to a REST end point on your server each time a message (reply or status) is processed. More detail about Pushing via Callbacks available here.
Does the 160 character limit for single messages apply before, or after URL encoding?
Before. The URL encoding is required in order for the request to be submitted to the eTXT API. Once we receive it it is decoded and then submitted to the carrier in a format that they require. If you are not setting a fragmentation limit on your request, then ensure that the message length is less than 160 characters before URL encoding it.
What content-types does eTXT API support?
We support Plain-Text and Unicode characters. We do not support Ringtones, IMelody, Operator Logos, or MMS