Before packaging a resource, there should be a check that the intended recipient MoodleNet site is reachable. The benefits of this are:

1. If there is a misconfiguration or connection issue between the LMS and MoodleNet sites, we can avoid packaging a resource that will inevitably fail to send. Incorporating “just in time” packaging avoids creating and storing a large number of MBZ files while an LMS site is unable to connect to the relevant MoodleNet site.
2. We can define some elegant backoff and failure mechanisms to handle short term issues or fail/cancel shares where the issue is not resolved (rather than them sitting pending forever without a resolution for the teacher).

Requirements

1. Create a method in the core\moodlenet API which can test whether a specified MoodleNet instance is reachable from the LMS.
2. This check should be called before packaging a resource, to ensure the MoodleNet site is reachable (and not perform the packaging if the check fails).
3. At the time of writing, there is no defined way to check this with MoodleNet (eg an endpoint to ping for availability). For our first pass in this issue, we could potentially send an invalid/empty request to the same endpoint as sharing a file, and checking we receive a response.

User stories

This issue helps to resolve the following user story:

1.  As a teacher, while I am waiting for my share to MoodleNet to complete, I will see multiple status updates, so I have a clear indication that the packaging and uploading of my resource is progressing.