Module machine 

The presence publisher’s decisions, apart from its I/O. Given what just happened (Event) and the time (Now), Machine::next settles the state, says what to do (Action) and how long to wait before the next Event::Due. Nothing here reads a clock, a random number or the network, so every rule is tested with a fake clock; super::Driver runs it against the relay.

state	entered on	next try
signed_out	no MuxBus sign-in	a sign-in (a local recheck every minute, no request)
publishing	the record was stored	a minute, or a change of the snapshot
retrying	unreachable, 5xx, 429, any other status	5 s doubling to 5 min, full jitter; a 429’s Retry-After
unsupported	404, no presence route	about 5 min; at once on a sign-in, a network change, a wake, or a new relay version
rejected	400 or 410	10 min or more
signed_off	a goodbye was stored at a sign-out	a sign-in
off	this install doesn’t publish (super::policy)	turned on

Outside publishing a change of the snapshot only marks it dirty: the next try sends the latest one, no sooner. A 409 means the relay already has a newer record of this install’s, which is as good as storing this one.

A goodbye (a v3 record, gone) is due when something was published and the relay takes v2 or later (Machine::farewell): an older relay would refuse v3, so it gets none. Turning publishing off says it here (Action::Goodbye); a sign-out and a quit say it from outside, and a sign-out tells the machine with Event::Goodbye.

Two refusals get an immediate second try before rejected: a record the relay can’t parse is sent again one version down, v4 then v2 then v1 (an older relay knows no agent lines, an older one still no states), and the version it took is then kept for that relay for Config::v1_memory; a record whose time the relay refuses is sent again stamped with the relay’s clock, learned from the Date of every answer.

Structs

Config 🔒

The waits, apart so tests can shorten them.

Farewell 🔒

A goodbye is due, stamped on the relay’s clock as far as it is known.

Followups 🔒

The second tries already spent on the record being sent.

Log 🔒

Machine 🔒

Now 🔒

The time, as the driver read it. mono_ms only ever grows and drives the waits; wall_ms is this computer’s clock, for the status and the record; rand is uniform in [0, 1), for jitter.

Step 🔒

Enums

Action 🔒

Answer 🔒

What the relay made of one record.

Event 🔒

Constants

CLOCK_NOTE_AFTER_MS 🔒

A clock further than this from the relay’s is shown in the status.

LIVE 🔒

LIVE_VERSION 🔒

The version a fresh try sends to a relay not known to be older.

MALFORMED_RECORD 🔒

The relay’s error for a record it can’t parse, which is what a relay that predates the record’s version answers.

Functions

classify 🔒

What the relay’s status and error mean for the publisher.

goodbye_text 🔒

minutes 🔒

“12 min”, rounded, at least 1.

ms 🔒

off_text 🔒

scaled 🔒

step_down 🔒

The version to try after v was refused as malformed, if any.