Stalwart 1.0 refuses Principal/query and Principal/getAvailability with
`forbidden` unless the administrator allows directory queries, which is
off by default. `getPrincipals` turned that into an empty list with no
signal: the share dialog said "No other users or groups found", existing
shares showed bare ids, and free/busy called every attendee "Not a user
on this server".
- `listPrincipals` says whether the listing is complete, `restricted`
or failed. On `forbidden` it falls back to Principal/get without ids,
which 1.0 still answers with the user's own account, their groups and
the accounts that shared something with them.
- Principal/get asks for `id`, `type`, `name`, `description` and
`email` only; 1.0's default list adds `capabilities` and `accounts`.
- One listing per client, kept for five minutes, serves the share
dialog, recipient autocomplete and free/busy, which used to download
the directory three times.
- The share dialog explains a restricted directory while still offering
its candidates, says when the list failed to load, and shows "Unknown
user" with the id for sharees it can't name.
- Free/busy first reads `mayGetAvailability` from the user's own
principal and stays hidden when it is false or a lookup is refused
with `forbidden`. "Not a user on this server" now needs a complete
listing; failures and `rateLimit` show "Couldn't check".
On 0.16 with the default roles the listing is complete and the dialog
behaves as before.
Linus Rath
6152e45b88