1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
//! Stable metric names emitted by the r402 stack.
//!
//! r402 instruments hot paths through the [`metrics`] facade so any
//! recorder (Prometheus, `StatsD`, OpenTelemetry, ...) can ingest the
//! counters and histograms without coupling the SDK to a specific
//! exporter. Operators install a recorder at startup; with no recorder
//! the macros expand to no-ops.
//!
//! # Naming
//!
//! All metrics use the `r402_` prefix and follow the [Prometheus naming
//! conventions]: `snake_case`, base-unit suffixes (`_seconds`, `_total`),
//! and a `_total` suffix for monotonically increasing counters.
//!
//! [`metrics`]: https://docs.rs/metrics/0.24
//! [Prometheus naming conventions]: https://prometheus.io/docs/practices/naming/
//!
//! # Cardinality
//!
//! Labels are bounded: `result` is one of three values per metric, and
//! we never include payer addresses, payment IDs, or signatures. This
//! keeps the cardinality flat and the recorder memory bounded even
//! under adversarial load.
/// Counter incremented every time a facilitator's `verify` returns.
///
/// Labels:
/// - `result` — `valid` for `VerifyResponse::Valid`, `invalid` for
/// `VerifyResponse::Invalid`, or `error` when the call returned a
/// structured `FacilitatorError`.
pub const FACILITATOR_VERIFY_TOTAL: &str = "r402_facilitator_verify_total";
/// Counter incremented every time a facilitator's `settle` returns.
///
/// Labels:
/// - `result` — `success` for `SettleResponse::Success`, `failure` for
/// `SettleResponse::Failure`, or `error` for transport / RPC errors.
pub const FACILITATOR_SETTLE_TOTAL: &str = "r402_facilitator_settle_total";
/// Histogram of facilitator `verify` durations in seconds.
pub const FACILITATOR_VERIFY_DURATION_SECONDS: &str = "r402_facilitator_verify_duration_seconds";
/// Histogram of facilitator `settle` durations in seconds.
pub const FACILITATOR_SETTLE_DURATION_SECONDS: &str = "r402_facilitator_settle_duration_seconds";
/// Counter incremented every time the settlement deduplication cache
/// observes a key.
///
/// Labels:
/// - `outcome` — `inserted` for newly seen keys, `duplicate` for hits.
pub const SETTLEMENT_CACHE_RESERVE_TOTAL: &str = "r402_settlement_cache_reserve_total";
/// Counter incremented per paygate request.
///
/// Labels:
/// - `outcome` — `paid` (settlement complete), `denied` (verify failure),
/// `aborted` (internal error before settlement could be attempted).
pub const PAYGATE_REQUEST_TOTAL: &str = "r402_paygate_request_total";
/// Counter incremented when the background settlement supervisor records
/// an outcome.
///
/// Labels:
/// - `result` — `ok`, `error`, `panic`, or `cancelled`.
pub const PAYGATE_BACKGROUND_SETTLE_TOTAL: &str = "r402_paygate_background_settle_total";