[Utility] B1: QoS - Single Check

Objective

Implement MVP E2E Feature Path A1: E2E Relay- Trustless Relay

Origin Document

Purpose: A Fisherman makes periodic relays to all Servicers during an active session, tracks the QoS of each request, and maintains the results in a local ephemeral state.

Actors: Check all of the protocol actors involved in the feature

[ ] Validator
[ ] Application
[x] Servicer
[x] Fisherman
[ ] Portal

Data Structures

MVP requirements for QoS need to be defined. Example:
- RoundTripTime (i.e. latency)
- Availability (i.e. responsive)
shared/core/types/proto/qos.proto needs to be created w/ data types to track QoS
runtime/genesis/proto/genesis.proto needs to be updated to govern how QoS checks are made based on the sampling protocol. Example:
- QoS check frequency per session
- QoS check distribution per session

Interfaces

shared/modules/utility_module.go will need to be updated with Fisherman specific interface logic for executing and storing a QoS check
app/client/cli/ may need to be updated if new endpoints are needed to be exposed to the client for the implementation of this feature

Diagram

sequenceDiagram
    actor F as Fisherman
    actor S1 as Servicer 1
    actor SN as Servicer N

        title E2E Single QoS Check

    loop Repeats During Session
        F ->> +S1: Relay Request
        F ->> +SN: Relay Request (identical)
        S1 ->> -F: Relay Response 1
                F ->> F: Record & Store<br>QoS for S1
        SN ->> -F: Relay Response N
                F ->> F: Record & Store<br>QoS for SN
    end

User Stories as Tests

Happy test cases
- A fisherman makes a successful request to a servicer that is available
- A fisherman makes a successful request to a servicer that has low latency
Sad test cases
- A fisherman makes successful request to a servicer that is unavailable
- A fisherman makes successful request to a servicer that has high latency

Blockers

E2E feature path dependencies:
- A.1: Trustless Relay
- E: All actors must be staked
Open Questions:
- How is a Fisherman notified that a session started?

Goals

Complete the MVP implementation of the E2E Feature Path outlined in the objective
Identify future tasks and test requirements to transition the feature to production

Deliverable

POC:
- [ ] A POC SPIKE to be closed out and split out into multiple PRs
MVP:
- [ ] A PR that adds or modifies relevant structures and interfaces; such as shared/core/types/proto, shared/modules, etc
- [ ] A PR that materializes an MVP of the feature along with unit tests
- [ ] A PR that introduces a new E2E tests with one happy and one sad path scenarios as described in the origin document (refer to e2e/README.md); this may require additions to the cli
- [ ] A PR that updates all pertinent documentation
PROD:
- [ ] One or more subsequent GitHub issues that track future work including, but not limited to:
- Enhancing test coverage
- Adding subsequent features
- Patching hacks or workarounds
- Enabling your imagination!

General issue deliverables

[ ] Update the appropriate CHANGELOG(s)
[ ] Update any relevant local/global README(s)
[ ] Update relevant source code tree explanations
[ ] Add or update any relevant or supporting mermaid diagrams

Testing Methodology

[ ] Task specific tests or benchmarks: make ...
[ ] New tests or benchmarks: make ...
[ ] All tests: make test_all
[ ] LocalNet: verify a LocalNet is still functioning correctly by following the instructions at docs/development/README.md
[ ] k8s LocalNet: verify a k8s LocalNet is still functioning correctly by following the instructions here

Creator: @Olshansk

pokt-network / pocket

[Utility] B1: QoS - Single Check #755