Crate sqry_daemon

Expand description

sqry-daemon — long-lived code-graph service.

The daemon (sqryd binary) owns one or more loaded code graphs in memory, watches source trees for changes, and serves CLI / LSP / MCP clients over a shared Unix-domain socket (named pipe on Windows). The goal is to amortise graph-load cost across every sqry invocation on a machine while preserving the semantic guarantees of direct-mode sqry (bijective per-file buckets, tombstone compaction, ArcSwap publish, etc.).

§Architecture at a glance

config — parses ~/.config/sqry/daemon.toml into a config::DaemonConfig with every tuning knob from the Amendment-2 design (memory limits, working-set multipliers, stale-serve age cap, debounce timing, interner compaction threshold, log rotation, socket path).
workspace (Task 6) — WorkspaceManager owns LoadedWorkspace state (§G admission accounting, §H rebuild plumbing, §F bijection check).
rebuild (Task 7) — per-workspace rebuild lane + coalescing (§J).
ipc (Task 8) — JSON-RPC over UDS with a standard response envelope.
lifecycle (Task 9) — pidfile locking, signal handling, service unit generators.
[client] (Task 10) — client library used by sqry-cli / sqry-lsp --daemon / sqry-mcp --daemon to connect to a running daemon and auto-start one if necessary.

Only config and the public error type DaemonError are in the surface today; later tasks in this plan land the other modules in order.

Re-exports§

pub use config::DEFAULT_IPC_SHUTDOWN_DRAIN_SECS;
pub use config::DaemonConfig;
pub use config::ESTIMATE_FINAL_PER_FILE_BYTES;
pub use config::ESTIMATE_STAGING_PER_FILE_BYTES;
pub use config::INTERNER_BUILDER_OVERHEAD_RATIO;
pub use config::SocketConfig;
pub use config::WORKING_SET_MULTIPLIER;
pub use config::WorkspaceConfig;
pub use error::DaemonError;
pub use error::DaemonResult;
pub use ipc::IpcServer;
pub use rebuild::RebuildDispatcher;
pub use rebuild::RebuildMode;
pub use rebuild::decide_mode;
pub use workspace::BACKOFF_SCHEDULE;
pub use workspace::DaemonStatus;
pub use workspace::LoadedWorkspace;
pub use workspace::MemoryStatus;
pub use workspace::NoOpHook;
pub use workspace::OldGraphToken;
pub use workspace::PendingRebuild;
pub use workspace::RealWorkspaceBuilder;
pub use workspace::RebuildReservation;
pub use workspace::ServeVerdict;
pub use workspace::SharedHook;
pub use workspace::SqrydHook;
pub use workspace::StalenessVerdict;
pub use workspace::WorkingSetInputs;
pub use workspace::WorkspaceBuilder;
pub use workspace::WorkspaceKey;
pub use workspace::WorkspaceManager;
pub use workspace::WorkspaceStatus;
pub use workspace::backoff_delay_for;
pub use workspace::classify_staleness;
pub use workspace::noop_hook;
pub use workspace::spawn_hook;
pub use workspace::working_set_estimate;

Modules§

config: Daemon configuration.
entrypoint: Task 9 U10 — production sqryd binary entry point.
error: Daemon-wide error type.
ipc: IPC surface of the sqryd daemon.
lifecycle: Task 9 — daemon binary lifecycle: pidfile locking, signal handling, service unit generators, log rotation, and auto-spawn primitives.
mcp_host: Phase 8c U8 — in-daemon MCP host.
rebuild: Rebuild dispatcher for the sqryd daemon (Task 7 Phase 7a + 7b1).
workspace: Workspace management — state machine + admission accounting.

Structs§

CancelRebuildResult: daemon/cancel_rebuild success result payload.
DaemonHello: Pre-handshake header sent as the very first frame by a CLI client. The server responds with DaemonHelloResponse before the JSON-RPC request loop begins.
DaemonHelloResponse: Server’s reply to DaemonHello. If compatible is false the server closes the connection immediately after the frame is sent.
JsonRpcError: JSON-RPC 2.0 error payload.
JsonRpcRequest: JSON-RPC 2.0 request.
JsonRpcResponse: JSON-RPC 2.0 response. id is Option<JsonRpcId> with no skip_serializing_if — the None case serialises as JSON null, which is exactly what the spec demands for parse-error and invalid-request responses.
JsonRpcVersion: JSON-RPC "2.0" version tag. Manual serde impls enforce exact string match on the wire so malformed requests never leak into the method dispatcher.
RebuildResult: daemon/rebuild success result payload (schema_version 2 — see cluster-G §2.4).
ResponseEnvelope: Uniform successful-response wrapper. Every successful method response is serialised as ResponseEnvelope<T> at the JSON-RPC result field — clients can rely on the ResponseMeta shape being present on every successful reply regardless of method.
ResponseMeta: Metadata attached to every successful response. For Phase 8a management methods the staleness fields are always absent (stale = false, no last_good_at, no last_error, workspace_state = None). Phase 8b populates them from the server-side ServeVerdict for tool-method responses.

Enums§

JsonRpcId: JSON-RPC id: null, integer (signed or unsigned), or string. I64 covers i64::MIN..=i64::MAX; U64 covers i64::MAX + 1..=u64::MAX. Serde’s untagged deserialize tries variants in order so 0..=i64::MAX lands in I64 and i64::MAX + 1..=u64::MAX in U64.
JsonRpcPayload: Tagged success-or-error payload. Serde untagged so the wire form is {... "result": ...} or {... "error": ...}, never both.
WorkspaceState: Six-state workspace lifecycle per plan Task 6 Step 1 and Amendment 2 §G.5 / §G.7.

Constants§

ENVELOPE_VERSION: Version of the daemon wire envelope (DaemonHelloResponse.envelope_version).
JSONRPC_INTERNAL_ERROR: JSON-RPC 2.0 standard “Internal error” code. Catch-all for errors bubbling from sqry_mcp::daemon_adapter tool execution that don’t map to a more specific DaemonError variant.
JSONRPC_INVALID_PARAMS: JSON-RPC 2.0 standard “Invalid params” error code.
JSONRPC_MEMORY_BUDGET_EXCEEDED: JSON-RPC error code: admission control could not satisfy a reservation after evicting every non-pinned workspace.
JSONRPC_QUERY_TOO_BROAD: JSON-RPC error code: pre-flight cost gate rejected a query because its evaluator cost is structurally unbounded (no scope filter, no regex anchoring, predicate shape would scan the full arena). Wire kind is always "query_too_broad". Reuses -32602 per the existing wire-bridge convention; kind is the discriminator (per B_cost_gate.md §3 “Why -32602, not a new -32xxx code”).
JSONRPC_RESET_CANCELLATION_DISPATCHED: JSON-RPC error code: daemon/reset was invoked on a workspace whose state is Rebuilding; cancellation has been dispatched and the caller is expected to retry after retry_after_ms for the state to settle into Failed / Unloaded (then a follow-up reset completes).
JSONRPC_RESET_WHILE_LOADING: JSON-RPC error code: daemon/reset was invoked on a workspace whose state is Loading and cannot be safely interrupted yet. Caller should retry once the load completes.
JSONRPC_SOCKET_SETUP: JSON-RPC error code: socket parent directory cannot be created or is not writable by the daemon’s uid. Surfaced before IpcServer::bind so the failure mode is a precise diagnostic instead of a generic EACCES from the eventual bind.
JSONRPC_TOOL_TIMEOUT: JSON-RPC error code: per-tool invocation exceeded DaemonConfig::tool_timeout_secs. Emitted by tool_core::classify_and_execute (Task 8 Phase 8c U6) when the tokio::time::timeout(tool_timeout, spawn_blocking(run)) outer timer fires. The detached JoinHandle is dropped — the OS thread may continue executing the tool closure but its result is discarded.
JSONRPC_WORKSPACE_BUILD_FAILED: JSON-RPC error code: workspace build failed and no prior good graph exists.
JSONRPC_WORKSPACE_EVICTED: JSON-RPC error code: the workspace was evicted or removed between a rebuild dispatch and its admission / publish commit. Callers must treat this as a terminal signal on the affected WorkspaceKey — subsequent dispatches require a fresh get_or_load first.
JSONRPC_WORKSPACE_INCOMPATIBLE_GRAPH: JSON-RPC error code: the on-disk graph snapshot or manifest cannot be loaded safely by this binary. Distinct from WorkspaceBuildFailed because it represents a path-policy / compatibility verdict (unknown plugin ids, unsupported snapshot format) rather than a transient build failure — clients react differently (rebuild vs. upgrade vs. retry).
JSONRPC_WORKSPACE_OVERSIZE: JSON-RPC error code: the freshly-built graph exceeds the daemon’s memory budget by itself (post-build oversize) — even after every other workspace would be evicted, the daemon cannot host this graph. Distinct from MemoryBudgetExceeded (-32003), which is a projected admission failure on a pre-build estimate.
JSONRPC_WORKSPACE_PINNED: JSON-RPC error code: daemon/reset refused because the targeted workspace is pinned and the caller did not pass force = true. Pinning is a per-workspace operator override; callers must opt in explicitly to drop a pinned workspace.
JSONRPC_WORKSPACE_STALE_EXPIRED: JSON-RPC error code: the workspace is serving a Failed state, but the last successful build is older than stale_serve_max_age_hours.