Struct Observation 

pub struct Observation {
    pub user_id: Uuid,
    pub last_seen_at: Option<DateTime<Utc>>,
    pub has_live_agent: bool,
    pub longest_finished_day: Option<(NaiveDate, i64, WorkdayKind)>,
    pub open_day: Option<(NaiveDate, DateTime<Utc>)>,
    pub work_rate: Decimal,
}

What the rules are evaluated against, for one person, at one moment.

A plain struct assembled by the sweep’s queries rather than the rows themselves, so every rule below is a function of values and can be tested without a database. The arithmetic is the part most worth testing, and logic inside a query can only be tested through one - the same reason the signals do their statistics in Rust.

Fields

user_id: Uuid

last_seen_at: Option<DateTime<Utc>>

When anything last arrived from any of this person’s live agents: the later of a request that used the token and a pulse. None for somebody whose agent has never said anything at all.

Both, and the freshest wins. agents.last_seen_at alone is what a first version of this rule read, and a live run against the demo showed what that costs: nine of twelve people flagged as silent, six of them having pulsed seconds earlier. The two stamps answer different questions - “the token was used” and “kasl is watching a person work” (ADR 0014) - and an agent can go a long time doing only the second: a machine whose employee is on holiday pulses idle all week and uploads nothing at all. Reading one of them is how a rule about silence alerts on somebody who is plainly talking.

has_live_agent: bool

Whether this person has any live agent token. Somebody with none is not silent - they were never asked to speak.

longest_finished_day: Option<(NaiveDate, i64, WorkdayKind)>

The finished day with the most seconds worked in the window the sweep looks at, as (date, worked_seconds, kind).

open_day: Option<(NaiveDate, DateTime<Utc>)>

A day still open, as (date, started_at). At most one: the schema allows a person one day per date, and a second open day would be a much louder problem than this rule.

work_rate: Decimal

This person’s share of a full day.

Trait Implementations

impl Clone for Observation

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Observation

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.