FerricStore.Flow.QueryEngine behaviour (ferricstore v0.11.0)

Installable execution boundary for canonical Flow queries.

OSS uses the bounded cost-aware planner. Extensions may inject trusted mandatory scope, authorization, budgets, and index metadata through the existing instance behaviours after parsing and parameter binding.

Summary

Types

capability_manifest()

context()

result()

Callbacks

capabilities()

execute(context, t)

Functions

capabilities(ctx)

deadline_ms(arg1)

Returns the absolute Unix-millisecond request deadline, when one was supplied.

execute(ctx, request, opts \\ [])

instance_context(ctx)

Returns the immutable FerricStore instance carried by an execution context.

request_context(arg1)

Returns trusted request authority carried by the execution context.

response_codec(arg1)

Returns the trusted query response codec selected by the protocol boundary.

Types

capability_manifest()

@type capability_manifest() :: %{
  request_contract: binary() | nil,
  result_contract: binary() | nil,
  explain_contract: binary() | nil,
  index_status_contract: binary() | nil,
  capabilities: [binary()],
  language_versions: [binary()],
  shapes: [binary()]
}

context()

@type context() ::
  FerricStore.Instance.t() | Ferricstore.Flow.Query.ExecutionContext.t() | map()

result()

@type result() :: {:ok, term()} | {:error, term()}

Callbacks

capabilities()

(optional)

@callback capabilities() :: capability_manifest()

execute(context, t)

@callback execute(context(), Ferricstore.Flow.Query.Request.t()) :: result()

Functions

capabilities(ctx)

@spec capabilities(context()) :: capability_manifest()

deadline_ms(arg1)

@spec deadline_ms(context()) :: pos_integer() | nil

Returns the absolute Unix-millisecond request deadline, when one was supplied.

Engines should convert this value to a monotonic deadline once at query initialization and use that value for subsequent budget checks.

execute(ctx, request, opts \\ [])

@spec execute(context(), Ferricstore.Flow.Query.Request.t(), keyword()) :: result()

instance_context(ctx)

@spec instance_context(context()) :: FerricStore.Instance.t() | map()

Returns the immutable FerricStore instance carried by an execution context.

Query-engine implementations should use this accessor instead of depending on the protocol layer's context wrapper.

request_context(arg1)

@spec request_context(context()) :: map()

Returns trusted request authority carried by the execution context.

Embedded calls and native requests without trusted authority return an empty map.

response_codec(arg1)

@spec response_codec(context()) ::
  Ferricstore.Flow.Query.ExecutionContext.response_codec()

Returns the trusted query response codec selected by the protocol boundary.

Embedded callers and contexts that do not carry a negotiated codec use the typed native-value representation.