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code-trace

Testing & Quality
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Trace a feature across the layered architecture (REST v2, GraphQL, Service, Repository, DB, Errors) and explore the entity source tree — includes how to read the 21k-line supergraph.graphql without loading it whole

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Code Trace

Locate where a feature lives across layers. The codebase is split per entity, so once you know the entity name (user, session, deployment, …) every layer is a predictable path.

Layer map ({entity} = entity name)

LayerPathWhat's there
REST v2 entrymanager/api/rest/v2/{entity}/registry.pyRouteRegistry — method + path + middleware → handler method
REST v2 handlermanager/api/rest/v2/{entity}/handler.pyV2{Entity}Handler — calls a Processor
GraphQL resolvermanager/api/gql/{entity}/resolver/{query,mutation}.pyStrawberry query/mutation resolvers
GraphQL typesmanager/api/gql/{entity}/types/node, inputs, payloads, filters, enums, scopes
GraphQL rootmanager/api/gql/schema.pyassembles all resolvers into the schema
Servicemanager/services/{entity}/service.py, processors.py, actions/, types.py
Repositorymanager/repositories/{entity}/repository.py, creators.py/updaters.py/purgers.py, db_source/
DB modelsmanager/models/SQLAlchemy tables
Errors{component}/errors/{domain}.pysee manager/errors/AGENTS.md

Flow: API handler → Processor → Service → Repository → DB. Handlers never call Services directly.

Trace a request end to end

  1. Find the entry: grep -rn "reg.add" manager/api/rest/v2/{entity}/registry.py (REST) or open gql/{entity}/resolver/.
  2. Follow the handler/resolver to its Processor, then to the Service method, then to the Repository.
  3. The Action (frozen dataclass) passed into the Service is in services/{entity}/actions/.

supergraph.graphql (21k lines) — never Read it whole

It is a generated single file. Extract only the block you need:

# find the line number of a type/input/query
grep -n "^type User\b\|^input .*User\|^type Query\|^type Mutation" supergraph.graphql

Then Read with offset/limit around that line. For the actual resolver logic, jump to the source under gql/{entity}/ instead — the schema only shows the contract.

Related

  • /api-guide — implement REST/GraphQL endpoints
  • /repository-guide, /service-guide — layer patterns
  • manager/errors/AGENTS.md — find/define exceptions