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Schema Context

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SchemaContext separates AST build concerns from runtime request concerns.

It has two context scopes:

  • SchemaBuildContext for schema.ast(...) and AST traversal.
  • SchemaRequestContext for parse, validate, runOperation, and publish flow.

Both are carried by one SchemaContext object:

  • getBuildContext / setBuildContext
  • getRequestContext / setRequestContext
  • state (shared request-state store)

Build context and request context flow​

Request execution sequence​

SchemaBuildContext fields​

  • buildId (string): unique build run id.
  • builder (AstBuilder): collected AST node registry.
  • parentNode (AstNode, optional): parent node while resolving nested schema.
  • schemaPath (string[]): path in schema tree.
  • buildOptions (Record<string, unknown>): custom build-time options.

SchemaRequestContext fields​

  • requestId (string): request correlation id for one schema execution.
  • timestamp (number): request start timestamp.
  • correlationId (string, optional): upstream request correlation.
  • sourceId (string, optional): caller/source identifier.
  • userId (string, optional): authenticated user id.
  • tenantId (string, optional): tenant identifier.
  • metadata (Record<string, unknown>, optional): request metadata.
  • state (SchemaState): mutable state store scoped to one request context.
  • publisher (Publisher, optional): publish integration for operation hooks.
  • onPublishError ((error, info) => void, optional): publish failure callback.
  • logger (Logger, optional): structured logging hooks.

Normalization behavior​

  • schema.ast(...) normalizes build context even if input is partial.
  • schema.parse(...) and validate(...) normalize request context when absent.
  • setRequestContext(...) preserves the same state instance across replacements.
  • Build context and request context stay independent and can exist separately.

Runtime integration​

In schemaModule, each inbound runtime envelope creates or overrides a request context, including metadata and publish wiring. envelope.context (runtime event context) is copied into emitted events, but it is not the same object as SchemaRequestContext.