Correlator gear
WARNING
Planned Feature (v0.4.3): The Correlator Gear is currently in the Architectural Proposal phase. This documentation serves as a technical reference for the intended design of "Parallel Mastering" within the Testing & Simulation Architecture.
The correlator gear functions as the Side-Chain Monitor of the payment mixer. It performs real-time Differential Analysis by comparing response signals from two independent signal pathstypically a Legacy System and a modernized Shadow System.
By "Monitoring the Mix" in parallel, enterprises can achieve risk-free migrations through continuous Parallel Mastering of their production logic.
| Attribute | Details |
|---|---|
| Type | correlator |
| Analogy | Side-Chain Monitor (Differential) |
| Status | Planned |
| Source Code | pkg/gears/native/correlator |
| Pairs With | Sniffer, Leveler |
| Port IN | live.in (from Sniffer), shadow.in (from Shadow Sink) |
| Port IN Cardinality | Multiple |
| Port OUT | shadow.req.out, shadow.res.out, out (Alerts) |
| Port OUT Cardinality | Multiple |
| Always Emitted Metadata | diff.status |
| Conditionally Emitted | diff.mismatches |
| Mandatory Consumed | [correlation_key] |
| Signals Sent | fluxrig.event.diff_alert (On Mismatch) |
The Side-Chain Flow
In fluxrig, the Correlator operates "Out-of-Band," receiving non-blocking signal taps from the production wire to ensure Mission-Critical Resilience.
Technical Differential Analysis
The Correlator ensures Signal Parity by validating both legs of a financial transaction (Ingress Request and Egress Response).
Shadow Mirroring (4-Leg Flow)
Instead of a "Big Bang" migration, the Correlator orchestrates a Parallel Run strategy:
- Ingress Request Leg: Captures the live request, injects it into the Modernized Switch, and verifies that the outbound "request signal" matches the legacy production message.
- Egress Response Leg: Captures the legacy response, injects it into the Shadow system, and verifies that the final "response signal" matches the legacy behavior bit-for-bit.
Differential Features
- Semantic Parity: Compares specific aliases (e.g.,
card.account) defined in the Leveler (Codec) rather than raw bytes. - Performance Benchmarking: Measures the signal latency of the Shadow system relative to the production path.
- Delta Reporting: Emits
fluxrig.event.diff_alertto the Control Plane on any signal mismatch.
Resilience & Safety
Designed with the Air-Gap First philosophy, the Correlator is Strictly Non-Blocking.
- Isolation: It consumes copies of data. Even if the Correlator process crashes, the "Live Mix" (Production Switch) remains unaffected.
- Security Gating: Respects the Protocol Orchestration Gateway masking rules, performing parity checks on tokenized data within the PCI zone.
TIP
Use the Correlator in conjunction with Robot Framework to generate human-readable "Parity Reports" for operational stakeholders.