Struct AnswerObservation 

pub struct AnswerObservation {
    pub observed_at: String,
    pub source: String,
    pub stale_after: Option<String>,
}

When the state behind an answer was read: the freshness contract of a capability answer.

Declared once and carried in the output type of every answer that is a picture of state, so that the output schema, OpenAPI, the MCP tool schemas and the command line’s JSON all carry it without a transport of their own. It is set where the state is read — the index build, the git read — never by the executor, which knows when a handler ran and not when the state it read was taken.

use std::time::{Duration, UNIX_EPOCH};
use majordomus_cli::index::AnswerObservation;
let at = UNIX_EPOCH + Duration::from_secs(1_788_000_000);
let o = AnswerObservation::taken("git read", at, Some(Duration::from_secs(120)));
assert_eq!(o.observed_at, "2026-08-29T10:40:00Z");
assert_eq!(o.stale_after.as_deref(), Some("2026-08-29T10:42:00Z"));
assert!(!o.is_stale_at(at + Duration::from_secs(120)));
assert!(o.is_stale_at(at + Duration::from_secs(121)));

Fields

observed_at: String

RFC 3339 UTC, whole seconds: when the state behind the answer was read. Empty only in an answer from an index that was never built (a hand-made one in a test).

source: String

What was read at that time: index build or git read.

stale_after: Option<String>

RFC 3339 UTC: after this the answer is not to be trusted as current even though nothing announced a change. Absent when there is no known blind spot.

Implementations

impl AnswerObservation

pub fn taken(source: &str, at: SystemTime, window: Option<Duration>) -> Self

An observation of source taken at at, trusted for window when there is one.

use std::time::UNIX_EPOCH;
use majordomus_cli::index::AnswerObservation;
let o = AnswerObservation::taken("index build", UNIX_EPOCH, None);
assert_eq!((o.observed_at.as_str(), o.stale_after), ("1970-01-01T00:00:00Z", None));

pub fn is_stale_at(&self, now: SystemTime) -> bool

Whether now is past Self::stale_after. RFC 3339 UTC in whole seconds is fixed width, so the comparison is of the strings.

use std::time::{Duration, UNIX_EPOCH};
use majordomus_cli::index::AnswerObservation;
let o = AnswerObservation::taken("git read", UNIX_EPOCH, None);
assert!(!o.is_stale_at(UNIX_EPOCH + Duration::from_secs(86_400)), "no window, never stale");

Trait Implementations

impl Clone for AnswerObservation

fn clone(&self) -> AnswerObservation

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for AnswerObservation

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

Formats the value using the given formatter.

impl Default for AnswerObservation

fn default() -> AnswerObservation

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for AnswerObservation

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for AnswerObservation

impl JsonSchema for AnswerObservation

fn schema_name() -> Cow<'static, str>

The name of the generated JSON Schema.

fn schema_id() -> Cow<'static, str>

Returns a string that uniquely identifies the schema produced by this type.

fn json_schema(generator: &mut SchemaGenerator) -> Schema

Generates a JSON Schema for this type.

fn inline_schema() -> bool

Whether JSON Schemas generated for this type should be included directly in parent schemas, rather than being re-used where possible using the $ref keyword.

impl PartialEq for AnswerObservation

fn eq(&self, other: &AnswerObservation) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for AnswerObservation

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for AnswerObservation