Purpose

This procedure is designed for using timeout in resending SMS flow.

Key Point

• In order to remove expired attempts records are saved in Redis db with expire parameter.

Input Parameters

• MAX_ATTEMPTS_COUNT - specifies the maximum number of retries before resend is rejected;

• SEND_TIMEOUT -specifies a number of seconds to wait to retry sending after an error condition ;(attempts.count() >= MAX_ATTEMPTS_COUNT);

• entity_name - i.e. “medication_request”;

• entity_id - i.e. medication_request_id.

Logic

1. Get array with all attempts which start with “{entity_name}:{entity_id}” from Redis db using script:

   [redis] KEYS $"{entity_name}:{entity_id}_*"

2. Get attempts.count();

3. If attempts.count() < MAX_ATTEMPTS_COUNT

   • generate attempt_id using structure: {entity_name}:{entity_id}_{datetime.now()},
     (i.e. "medication_request:b075f148-7f93-4fc2-b2ec-2d81b19a9b7_2022-12-22T10:30:45.255687")

   • save attempt to Redis db using attempt_id as key and datetime.now() as value using script:

     [redis] set attempt_id $"{datetime.now()}"

   • set timeout to attempt with SEND_TIMEOUT parameter using script:

     [redis] expire key SEND_TIMEOUT

   • return 200 (ok).20

4. Else (attempts.count() >= MAX_ATTEMPTS_COUNT)

   • do not save attempt;

   • return error 429 ("Sending SMS timeout. Try later. Next attempt will be available at <attempts.oldest.value + SEND_TIMEOUT>").