Platform Notes | UStore for Mojo

§ What This Binding Does Not Expose

The five Arrow exports of c/ustore/arrow.h stay unbound, as Mojo has no Arrow arrays to hand them. The accessor layout of a strings batch, which reads strings through a C callback, is not exposed: Mojo passes the two tape layouts.

§ Design

Blocking stays simple: a verb on a database or on db.on(executor) reads as it would if asynchrony did not exist. Deferred calls are symmetric, the same verbs on another receiver, observed only through the outcome’s status word, and release rides Mojo’s own destructor. Nothing costs anything until used: the binding starts no threads, keeps no counts and caches nothing, so a call is one argument structure built on the stack and one indirect call.

API

StructLibraryA reference to the loaded engine, cheap to copy and shared by everything it creates.53

struct Library

Every handle carries one, which is what keeps the shared object mapped for as long as anything can still call into it.

Fields

`shared`	`ArcPointer[_Loaded]`	The handle and its symbols, refcounted so the last holder unmaps the object.

Conforms to

Copyable, Deinitable, ImplicitlyCopyable, Movable

__init__Opens the shared object and resolves it, which every handle then shares.

def __init__(out self)

Raises

With LIBRARY_MISSING, when nothing is on the loader path, with VERSION_MISMATCH when what loaded is another major version, or with SYMBOL_MISSING when it does not export an entry point the binding needs.

symbolsThe resolved entry points, borrowed rather than copied on every call.

def symbols(self) -> ref[self.shared.symbols] Symbols

versionThe loaded engine's major, minor and patch. Calls ustore_version.

def version(self) -> Tuple[Int, Int, Int]

version_nameThe loaded engine's own version, like "1.0.0". Calls ustore_version_name.

def version_name(self) -> String

gpu_devicesFills devices with every GPU this process can drive, in the ordinal order a VRAM executor names them by. Calls ustore_gpu_devices.

def gpu_devices[devices_origin: MutOrigin, //](
    self,
    devices: Span[GPUDevice, devices_origin]
) -> Int

Parameters

`devicesSpan[GPUDevice, devices_origin]`		Where the listing lands, as many entries as fit; may be empty to only count.

Returns

How many devices this process can drive, which may exceed len(devices).

status_nameThe engine's spelling of a status, "unrecognized" for a code it does not name. Calls ustore_status_name.

def status_name(self, status: Status) -> String

status_from_nameReads a spelling back; INVALID_ARGUMENT when unrecognized. Calls ustore_status_from_name.

def status_from_name(self, name: StringSpan) -> Status

pattern_kind_nameThe engine's spelling of a pattern kind. Calls ustore_pattern_kind_name.

def pattern_kind_name(self, kind: PatternKind) -> String

pattern_kind_from_nameReads a spelling back; REGEX when unrecognized. Calls ustore_pattern_kind_from_name.

def pattern_kind_from_name(self, name: StringSpan) -> PatternKind

case_sensitivity_nameThe engine's spelling of a case sensitivity. Calls ustore_case_sensitivity_name.

def case_sensitivity_name(self, sensitivity: CaseSensitivity) -> String

case_sensitivity_from_nameReads a spelling back; CASED when unrecognized. Calls ustore_case_sensitivity_from_name.

def case_sensitivity_from_name(self, name: StringSpan) -> CaseSensitivity

mood_nameThe engine's spelling of a mood. Calls ustore_mood_name.

def mood_name(self, mood: Mood) -> String

mood_from_nameReads a spelling back; PARKED when unrecognized. Calls ustore_mood_from_name.

def mood_from_name(self, name: StringSpan) -> Mood

cpu_class_nameThe engine's spelling of a CPU class, "automatic" for UNKNOWN. Calls ustore_cpu_class_name.

def cpu_class_name(self, cpu_class: CPUClass) -> String

cpu_class_from_nameReads a spelling back; UNKNOWN when unrecognized. Calls ustore_cpu_class_from_name.

def cpu_class_from_name(self, name: StringSpan) -> CPUClass

transport_nameThe engine's spelling of a transport. Calls ustore_transport_name.

def transport_name(self, transport: Transport) -> String

transport_from_nameReads a spelling back; AUTOMATIC when unrecognized. Calls ustore_transport_from_name.

def transport_from_name(self, name: StringSpan) -> Transport

gds_nameThe engine's spelling of a GPUDirect Storage mode. Calls ustore_gds_name.

def gds_name(self, gds: Gds) -> String

gds_from_nameReads a spelling back; AUTOMATIC when unrecognized. Calls ustore_gds_from_name.

def gds_from_name(self, name: StringSpan) -> Gds

gpu_vendor_nameThe engine's spelling of a GPU vendor. Calls ustore_gpu_vendor_name.

def gpu_vendor_name(self, vendor: GPUVendor) -> String

gpu_vendor_from_nameReads a spelling back; UNKNOWN when unrecognized. Calls ustore_gpu_vendor_from_name.

def gpu_vendor_from_name(self, name: StringSpan) -> GPUVendor

gpu_class_nameThe engine's spelling of a GPU class. Calls ustore_gpu_class_name.

def gpu_class_name(self, gpu_class: GPUClass) -> String

gpu_class_from_nameReads a spelling back; UNKNOWN when unrecognized. Calls ustore_gpu_class_from_name.

def gpu_class_from_name(self, name: StringSpan) -> GPUClass

predicate_cost_nameThe engine's spelling of a predicate cost. Calls ustore_predicate_cost_name.

def predicate_cost_name(self, cost: PredicateCost) -> String

predicate_cost_from_nameReads a spelling back; CHEAP when unrecognized. Calls ustore_predicate_cost_from_name.

def predicate_cost_from_name(self, name: StringSpan) -> PredicateCost

durability_nameThe engine's spelling of a durability. Calls ustore_durability_name.

def durability_name(self, durability: Durability) -> String

durability_from_nameReads a spelling back; BUFFERED when unrecognized. Calls ustore_durability_from_name.

def durability_from_name(self, name: StringSpan) -> Durability

watch_nameThe engine's spelling of a watch. Calls ustore_watch_name.

def watch_name(self, watch: Watch) -> String

watch_from_nameReads a spelling back; KEYS when unrecognized. Calls ustore_watch_from_name.

def watch_from_name(self, name: StringSpan) -> Watch

scan_mode_nameThe engine's spelling of a scan mode. Calls ustore_scan_mode_name.

def scan_mode_name(self, mode: ScanMode) -> String

scan_mode_from_nameReads a spelling back; ORDERED when unrecognized. Calls ustore_scan_mode_from_name.

def scan_mode_from_name(self, name: StringSpan) -> ScanMode

scan_direction_nameThe engine's spelling of a scan direction. Calls ustore_scan_direction_name.

def scan_direction_name(self, direction: ScanDirection) -> String

scan_direction_from_nameReads a spelling back; ASCENDING when unrecognized. Calls ustore_scan_direction_from_name.

def scan_direction_from_name(self, name: StringSpan) -> ScanDirection

drop_mode_nameThe engine's spelling of a drop mode. Calls ustore_drop_mode_name.

def drop_mode_name(self, mode: DropMode) -> String

drop_mode_from_nameReads a spelling back; COLLECTION when unrecognized. Calls ustore_drop_mode_from_name.

def drop_mode_from_name(self, name: StringSpan) -> DropMode

isolation_nameThe engine's spelling of an isolation. Calls ustore_isolation_name.

def isolation_name(self, isolation: Isolation) -> String

isolation_from_nameReads a spelling back; STRICT_SERIALIZABLE when unrecognized. Calls ustore_isolation_from_name.

def isolation_from_name(self, name: StringSpan) -> Isolation

engine_nameThe engine's spelling of an engine. Calls ustore_engine_name.

def engine_name(self, engine: Engine) -> String

engine_from_nameReads a spelling back; RAM when unrecognized. Calls ustore_engine_from_name.

def engine_from_name(self, name: StringSpan) -> Engine

modality_nameThe engine's spelling of a modality. Calls ustore_modality_name.

def modality_name(self, modality: Modality) -> String

modality_from_nameReads a spelling back; NONE when unrecognized. Calls ustore_modality_from_name.

def modality_from_name(self, name: StringSpan) -> Modality

change_kind_nameThe engine's spelling of a change kind. Calls ustore_change_kind_name.

def change_kind_name(self, kind: ChangeKind) -> String

change_kind_from_nameReads a spelling back; WRITE when unrecognized. Calls ustore_change_kind_from_name.

def change_kind_from_name(self, name: StringSpan) -> ChangeKind

ingest_order_nameThe engine's spelling of an ingest order. Calls ustore_ingest_order_name.

def ingest_order_name(self, order: IngestOrder) -> String

ingest_order_from_nameReads a spelling back; SORTED when unrecognized. Calls ustore_ingest_order_from_name.

def ingest_order_from_name(self, name: StringSpan) -> IngestOrder

docs_field_type_nameThe engine's spelling of a field type, as F64 spells "f64". Calls ustore_docs_field_type_name.

def docs_field_type_name(self, field_type: FieldType) -> String

docs_field_type_from_nameReads a spelling back; JSON when unrecognized. Calls ustore_docs_field_type_from_name.

def docs_field_type_from_name(self, name: StringSpan) -> FieldType

docs_modification_nameThe engine's spelling of a modification. Calls ustore_docs_modification_name.

def docs_modification_name(self, modification: Modification) -> String

docs_modification_from_nameReads a spelling back; UPSERT when unrecognized. Calls ustore_docs_modification_from_name.

def docs_modification_from_name(self, name: StringSpan) -> Modification

vertex_role_nameThe engine's spelling of a vertex role. Calls ustore_vertex_role_name.

def vertex_role_name(self, role: VertexRole) -> String

vertex_role_from_nameReads a spelling back; UNKNOWN when unrecognized. Calls ustore_vertex_role_from_name.

def vertex_role_from_name(self, name: StringSpan) -> VertexRole

page_encoding_nameThe engine's spelling of a page encoding. Calls ustore_page_encoding_name.

def page_encoding_name(self, encoding: PageEncoding) -> String

page_encoding_from_nameReads a spelling back; HTML when unrecognized. Calls ustore_page_encoding_from_name.

def page_encoding_from_name(self, name: StringSpan) -> PageEncoding

StructPageEncodingThe encoding a page or a fragment is imported from or rendered into, ustore_page_encoding_t.

struct PageEncoding

Fields

`code`	`c_int`	The raw `ustore_page_encoding_t` value the ABI exchanges.

Values

`HTML`	`PageEncoding(Int32(0))`	HTML, not yet imported or rendered, answering `UNSUPPORTED`.
`XML`	`PageEncoding(Int32(1))`	XML, with every element and attribute kept as written.
`MARKDOWN`	`PageEncoding(Int32(2))`	Markdown, not yet imported or rendered, answering `UNSUPPORTED`.
`TEXT`	`PageEncoding(Int32(3))`	The text of every run in document order, with structure dropped.
`JSON`	`PageEncoding(Int32(4))`	The element tree as JSON, not yet imported or rendered, answering `UNSUPPORTED`.

Conforms to

Copyable, Deinitable, Equatable, ImplicitlyCopyable, Movable, RegisterPassable, TrivialRegisterPassable

StructPagesInsertConfigWhere inserted fragments land, the keys they take, and how they read.1

struct PagesInsertConfig[elements_origin: ImmOrigin = ImmUntrackedOrigin, parents_origin: ImmOrigin = ImmUntrackedOrigin, anchors_origin: ImmOrigin = ImmUntrackedOrigin]

Parameters

`elements_originImmOrigin`	comptime	The borrowed element keys.
`parents_originImmOrigin`	comptime	The borrowed parents.
`anchors_originImmOrigin`	comptime	The borrowed anchors.

Fields

`elements`	`StridedView[Key, elements_origin]`	Keys to give the inserted elements; nil or zeroed mints one.
`parents`	`StridedView[Key, parents_origin]`	Parents the elements land under; nil stands for the root.
`anchors`	`StridedView[Key, anchors_origin]`	Siblings after which the elements land; nil stands for the front.
`encoding`	`PageEncoding`	Encoding of the fragments.
`durability`	`Durability`	How durable the edits are once the call finishes at the head.

Conforms to

Copyable, Deinitable, ImplicitlyCopyable, Movable

__init__Names only the knobs that differ from the defaults.

def __init__(
    out self,
    *,
    elements: StridedView[Key, elements_origin] = StridedView(),
    parents: StridedView[Key, parents_origin] = StridedView(),
    anchors: StridedView[Key, anchors_origin] = StridedView(),
    encoding: PageEncoding = PageEncoding.XML,
    durability: Durability = Durability.BUFFERED
)

StructPagesReadConfigWhich subtrees a read renders, and into what.1

struct PagesReadConfig[elements_origin: ImmOrigin = ImmUntrackedOrigin]

Parameters

`elements_originImmOrigin`	comptime	The borrowed element keys.

Fields

`elements`	`StridedView[Key, elements_origin]`	Elements to render with their subtrees; zeroed or nil renders whole pages.
`outputs_encoding`	`PageEncoding`	Encoding the renderings are converted into.
`values`	`Bool`	Whether the renderings come too, or only presences and lengths.

Conforms to

Copyable, Deinitable, ImplicitlyCopyable, Movable

__init__Names only the knobs that differ from the defaults.

def __init__(
    out self,
    *,
    elements: StridedView[Key, elements_origin] = StridedView(),
    outputs_encoding: PageEncoding = PageEncoding.XML,
    values: Bool = True
)

StructPagesScanConfigThe bounds, order and filter of a scan over page keys.1

struct PagesScanConfig[end_origin: ImmOrigin = ImmUntrackedOrigin, filter_origin: ImmOrigin = ImmUntrackedOrigin]

Parameters

`end_originImmOrigin`	comptime	The borrowed end keys.
`filter_originImmOrigin`	comptime	The borrowed filter.

Fields

`end_keys`	`StridedView[Key, end_origin]`	Key every scan stops before, exclusive; zeroed bounds nothing.
`direction`	`ScanDirection`	Ascending or descending from the start keys.
`mode`	`ScanMode`	In what order the page keys come.
`filter`	`BytesView[filter_origin]`	A path in StringZilla's XPath subset every listed page holds a node of; zeroed lists every page.
`predicate`	`Predicate`	The caller's verdict on the listed keys.
`progress`	`Progress`	Reports the scans finished, and stops the call where it says to.

Conforms to

Copyable, Deinitable, ImplicitlyCopyable, Movable

__init__Names only the knobs that differ from the defaults.

def __init__(
    out self,
    *,
    end_keys: StridedView[Key, end_origin] = StridedView(),
    direction: ScanDirection = ScanDirection.ASCENDING,
    mode: ScanMode = ScanMode.ORDERED,
    filter: BytesView[filter_origin] = BytesView(),
    predicate: Predicate = Predicate(),
    progress: Progress = Progress()
)