v2 Documentation

[julienrbrt]

Once #21429 is completed, we should focus on the documentation and upgrading documentation for docs.cosmos.network/v2 for Cosmos SDK (server) v2.

The removal of baseapp and change of all core concepts will require quite an overhaul.

Documentation

Core Concepts

• STF
  • Branching
• Server Components
• Runtime/v2
• Store/v2
  • Different database backend ss/sc
• IAVL v2

App

• Use runtime/v2 and simapp/v2

CometBFT server

• CometBFT server
• ABCI
• Optimistic Execution on by default and cannot be disabled.

Modules

Module documentation changes are limited compared to #21429 thanks to core v1:

• TxValidators
• Handlers (Optional, gRPC services are still supported)
  • If you use handler, no gRPC service will be available for that module

Testing

• integration tests framework v2
• sims v2
• systemtests

Upgrading Guide

• Create a UPGRADING_V2.md

Modules

• sdk.Context to core service migration: https://hackmd.io/@julienrbrt/S16-_Vq50
• AnteHandler to TxValidator
• Optional migration from grpc services to handlers
• [Documentation]: Module configuration #22371

Server

• Telemetry server is another port (1328)
• New REST server for querying modules (8080) -> Use post and type_url (docs at server/v2/api/rest/README.md)
• gRPC: new service to query the modules gRPC messages, without going via module services
• gRPC: external gRPC services no more registered in the application router (e.g. nodeservice, cmtservice, authtx service)

App

• Use runtime/v2 and simapp/v2 (no brainer)