Struct FirebaseAdapter 

pub struct FirebaseAdapter { /* private fields */ }

A Firebase Realtime Database (subtree), exposed as an arbor.

Implementations

impl FirebaseAdapter

pub fn connect(target: &str) -> Result<Self, FirebaseError>

Connect to firebase://HOST/BASE/PATH[?QUERY]. Verifies the target answers (one shallow GET of the root).

pub fn connect_with_refs( target: &str, refs: Refs, ) -> Result<Self, FirebaseError>

[connect], with a declared reference schema (see the module doc): bare ~> and -> crosslinks work for the declared fields.

pub fn locator(&self, node: NodeId) -> String

A human-readable locator: the RTDB path.

Trait Implementations

impl AstAdapter for FirebaseAdapter

fn children_named(&self, node: NodeId, name: &str) -> Vec<NodeId>

Name-addressed navigation — the path through opaque containers (one direct GET; no enumeration). Enumerated containers answer from their key set without a request.

fn traits(&self, node: NodeId) -> Vec<String>

The JSON kind, once known: <object> / <string> / <number> / <boolean>.

fn property(&self, node: NodeId, name: &str) -> Option<Value>

::field — one direct GET of path/field.json.

fn default_value(&self, node: NodeId) -> Option<Value>

A scalar projects to its value; a container has no default projection.

fn metadata(&self, node: NodeId, key: &str) -> Option<Value>

;;;type, ;;;length (children of a container), and ;;;path (the RTDB path — the node’s address in the database).

fn resolve( &self, node: NodeId, property: &str, hint: Option<&str>, ) -> Option<NodeId>

Hint-based only (RTDB has no schema): ::parent~>item reads the parent field and lands on <base>/item/<value> — the hint names a root-relative container, like the relational adapters’ target table.

fn links(&self, node: NodeId) -> Vec<(String, NodeId)>

Every declared field with a value is an outgoing crosslink, labeled by the field name; a field/* declaration yields one edge per array element. Each edge is probed (one GET) so dangling references stay out.

fn root(&self) -> NodeId

The root node — the initial navigation context.

fn children(&self, node: NodeId) -> Vec<NodeId>

The tree children of node, in document order.

fn name(&self, node: NodeId) -> Option<String>

The name of node — the label of its incoming tree edge.

fn parent(&self, node: NodeId) -> Option<NodeId>

The parent of node, or None for the root.

fn backlinks(&self, _node: NodeId) -> Vec<(String, NodeId)>

Incoming crosslinks to node, as (label, source) pairs, for <- navigation. May be expensive (an adapter that does not precompute edges must search for referrers).

fn link_property( &self, _source: NodeId, _label: &str, _target: NodeId, _name: &str, ) -> Option<Value>

A property of the crosslink source --label--> target — the $-::prop read. Adapters whose edges carry data (a property graph’s relationship properties) override this; None if the edge is bare or unknown. Where parallel edges share source, label, and target, the adapter answers for one of them, consistently.

fn quantifier_bound(&self) -> usize

The quantifier bound N_max: the depth to which open-ended path quantifiers (+, *, {m,}) expand, and the ceiling of any explicit {m,n} (the effective upper bound is min(n, N_max)). An adapter whose natural structures run deep may raise it; the CLI overrides it per run (qua --quantifier-bound).

fn allow_shell(&self) -> bool

Whether the sh(...) pipeline stage may run external commands. False by default — query text stays inert data — and enabled per run by the CLI (qua --allow-shell) through the AllowShell wrapper.

fn invocation_instant(&self) -> Option<(i64, u32)>

The invocation instant now() denotes (spec: The Temporal Fragment, Determinism): one UTC timeline point bound by the runner BEFORE evaluation begins — evaluation itself never reads a clock. None by default (a library run is fully deterministic; now() reads as null); the CLI binds it at startup — pinnable with qua --now — through the WithNow wrapper.

fn unit_scale(&self, expr: &str) -> Option<(f64, String)>

The scale of a unit expression — (factor, canonical SI-base expansion) — for the unital reading’s criterion text (spec: The Quantital Fragment). The default answers from the engine’s frozen built-in table; a unit-aware adapter (kaiv) overrides it to include the mounted document’s own custom units, so [::range < '50kellicam'] resolves through the document’s .!units imports.