Class: QueryNode<TArgs, TState>#

Defined in: retree-query/src/QueryNode.ts:57

Backend-agnostic reactive query node that subscribes to an async source and writes emitted values into Retree state.

Remarks#

The node owns the full async-query state machine:

• Status/result: pending, success (optionally isStale with keepPreviousData), error, and skipped.
• Subscription lifecycle: the source is subscribed when the node gains its first Retree observer and disposed when it loses its last one; disposal is sticky until the node is observed again (or QueryNode.retry runs after an error).
• Args lifecycle: QueryNode.updateArgs resubscribes only when arguments change under deep comparison.
• Optimistic updates: QueryNode.optimisticUpdate applies local transforms with generation tracking and rejection-time baseline rollback.
• Reconciliation: an optional IStateReconciler keeps object identity stable across emissions.

Backends plug in through IQuerySubscriptionSource. Subclasses (for example ConvexQueryNode in @retreejs/convex) bind a concrete client and may override the protected hooks (tryDefaultReconcile, cloneState, stateEquals, restoreState) for backend-specific state shapes.

Example#

const node = Retree.root(
    new QueryNode(mySource, { args: { listId: "today" } })
);

Retree.on(node, "nodeChanged", (next) => {
    console.log(next.result.status);
});

Extends#

• ReactiveNode

Type Parameters#

Constructors#

Constructor#

new QueryNode<TArgs, TState>(source, options): QueryNode<TArgs, TState>;

Defined in: retree-query/src/QueryNode.ts:142

Create a node for an async query subscription.

Parameters#

Returns#

QueryNode<TArgs, TState>

Remarks#

The subscription starts when the node is observed by Retree. This avoids opening backend subscriptions for state nobody is currently rendering or listening to.

Example#

const node = Retree.root(
    new QueryNode(mySource, {
        args: { listId: "today" },
        initialState: [],
    })
);

Overrides#

ReactiveNode.constructor

Properties#

Accessors#

dependencies#

Get Signature#

get dependencies(): never[];

Defined in: retree-query/src/QueryNode.ts:157

Dependencies to listen for changes to.

Remarks

When any IReactiveDependency criteria is met, a change will be emitted for this ReactiveNode instance.

Defaults to [] (no dependencies). Subclasses only override this getter when the node should emit for changes to other nodes; plain state classes need no dependencies boilerplate.

Keep this getter deterministic. Do not start subscriptions, perform network work, or mutate state here. Use ReactiveNode.onObserved, ReactiveNode.onUnobserved, and ReactiveNode.onChanged for lifecycle work.

The returned array may change length or ordering while the node is observed. Retree treats added, removed, or reordered entries as invalidation and refreshes subscriptions. Use null when you want an inactive slot to keep its position, but it is not required for correctness.

Example

class ProjectSummary extends ReactiveNode {
    public tasks: { done: boolean }[] = [];

    get doneCount() {
        return this.tasks.filter((task) => task.done).length;
    }

    get dependencies() {
        return [this.dependency(this.tasks, [this.doneCount])];
    }
}

Returns

never[]

Overrides#

ReactiveNode.dependencies

queryNodeName#

Get Signature#

get protected queryNodeName(): string;

Defined in: retree-query/src/QueryNode.ts:165

Name used in error and warning messages so failures pinpoint the concrete node class. Subclasses override this with their class name.

Returns

string

Methods#

cloneState()#

protected cloneState(state): TState | undefined;

Defined in: retree-query/src/QueryNode.ts:593

Clone a state value for optimistic rollback baselines.

Parameters#

Returns#

TState | undefined

Remarks#

The base implementation uses structuredClone over the raw view, which supports every structured-cloneable value including bigint and ArrayBuffer. Subclasses whose state carries non-cloneable members (such as functions) override this.

dependency()#

Call Signature#

dependency<TNode>(node, comparisons?): IReactiveDependency<TNode>;

Defined in: retree-core/bin/ReactiveNode.d.ts:413

Creates a new IReactiveDependency instance.

Type Parameters

Parameters

Returns

IReactiveDependency<TNode>

dependency object.

Remarks

Use this inside the ReactiveNode.dependencies getter or an @select dependency selector when one slot needs explicit comparison cells. If node is a Retree-managed object, it is observed with nodeChanged. If node is a primitive or unproxied value, Retree treats it as a comparison-only dependency.

Comparison cells should be deterministic. If their length/order changes, Retree treats that as invalidation and emits for this node. If no comparisons are provided, every nodeChanged event from the dependency emits for this node.

Example

get dependencies() {
    return [
        this.authStore,
        this.authStore.session?.userId,
        this.dependency(this.selectedProject ?? null, [this.projectId]),
    ];
}

Inherited from

ReactiveNode.dependency

Call Signature#

dependency<TValue>(value): IReactiveDependency;

Defined in: retree-core/bin/ReactiveNode.d.ts:414

Creates a new IReactiveDependency instance.

Type Parameters

Parameters

Returns

IReactiveDependency

dependency object.

Remarks

Use this inside the ReactiveNode.dependencies getter or an @select dependency selector when one slot needs explicit comparison cells. If node is a Retree-managed object, it is observed with nodeChanged. If node is a primitive or unproxied value, Retree treats it as a comparison-only dependency.

Comparison cells should be deterministic. If their length/order changes, Retree treats that as invalidation and emits for this node. If no comparisons are provided, every nodeChanged event from the dependency emits for this node.

Example

get dependencies() {
    return [
        this.authStore,
        this.authStore.session?.userId,
        this.dependency(this.selectedProject ?? null, [this.projectId]),
    ];
}

Inherited from

ReactiveNode.dependency

dispose()#

dispose(): void;

Defined in: retree-query/src/QueryNode.ts:564

Stop the active backend subscription.

Returns#

void

Remarks#

Retree calls this automatically when the node loses its last active observer. Call it manually when tearing the owner down outside Retree observation. Disposing stops future backend updates; it does not clear state, result, or error.

Disposal is sticky: writes to the node no longer reopen the subscription. The node resubscribes when it gains a new observer, or when QueryNode.retry runs after an error.

link()#

link<TNode>(node): RetreeLink<TNode>;

Defined in: retree-core/bin/ReactiveNode.d.ts:167

Create a reactive pointer to an existing Retree-managed node.

Type Parameters#

Parameters#

Returns#

RetreeLink<TNode>

A Retree-managed RetreeLink whose current points at node.

Remarks#

This is a convenience wrapper around Retree.link. Use it when a ReactiveNode method needs to return or store a pointer to a node owned elsewhere without reparenting that node.

Do not use link when ownership should move; use Retree.move or ReactiveNode.moveTo. Do not use it when two locations need independent state; use Retree.clone.

Example#

class EditorState extends ReactiveNode {
    public selected = null as RetreeLink<Task> | null;

    public select(task: Task) {
        this.selected = this.link(task);
    }
}

Inherited from#

ReactiveNode.link

memo()#

Call Signature#

protected memo<T>(fn, comparisons?): T;

Defined in: retree-core/bin/ReactiveNode.d.ts:486

Memoize the result of fn, scoped to this ReactiveNode instance.

Type Parameters

Parameters

Returns

T

Remarks

Two forms:

• Keyless (inside a getter): this.memo(fn, deps?) — derives the cache key from the active getter's property name. Throws if called outside a getter or more than once in the same getter.
• Explicit key: this.memo(key, fn, deps?) — works anywhere; required when stacking multiple memo cells in one getter, or memoizing inside a method.

Cache semantics for comparisons:

• Omitted/undefined: run fn under automatic dependency trapping and recompute when one of the trapped reads changes.
• []: compute once and cache forever for this instance.
• [a, b, ...]: recompute when any cell shallow-changes using Object.is. Tree-node cells are compared by their latest reproxy identity, so passing this.list correctly invalidates when list mutates.

memo is a cache, not a subscription. It does not emit nodeChanged or trigger React renders by itself. Pair it with dependencies, Retree.select, or useSelect when you also need notification behavior.

Example

class ListFilter extends ReactiveNode {
   list: Card[] = [];
   searchText = "";
   // Keyless form
   get filteredList() {
       return this.memo(
           () => this.list.filter((c) => c.text === this.searchText),
           [this.list, this.searchText]
       );
   }
   // Explicit-key form (e.g. when stacking two memos in one getter)
   get pair() {
       const a = this.memo("a", () => expensiveA(), [this.list]);
       const b = this.memo("b", () => expensiveB(), [this.searchText]);
       return { a, b };
   }
   get dependencies() { return [this.dependency(this.list)]; }
}

Inherited from

ReactiveNode.memo

Call Signature#

protected memo<T>(
   key, 
   fn, 
   comparisons?): T;

Defined in: retree-core/bin/ReactiveNode.d.ts:487

Memoize the result of fn, scoped to this ReactiveNode instance.

Type Parameters

Parameters

Returns

T

Remarks

Two forms:

• Keyless (inside a getter): this.memo(fn, deps?) — derives the cache key from the active getter's property name. Throws if called outside a getter or more than once in the same getter.
• Explicit key: this.memo(key, fn, deps?) — works anywhere; required when stacking multiple memo cells in one getter, or memoizing inside a method.

Cache semantics for comparisons:

• Omitted/undefined: run fn under automatic dependency trapping and recompute when one of the trapped reads changes.
• []: compute once and cache forever for this instance.
• [a, b, ...]: recompute when any cell shallow-changes using Object.is. Tree-node cells are compared by their latest reproxy identity, so passing this.list correctly invalidates when list mutates.

memo is a cache, not a subscription. It does not emit nodeChanged or trigger React renders by itself. Pair it with dependencies, Retree.select, or useSelect when you also need notification behavior.

Example

class ListFilter extends ReactiveNode {
   list: Card[] = [];
   searchText = "";
   // Keyless form
   get filteredList() {
       return this.memo(
           () => this.list.filter((c) => c.text === this.searchText),
           [this.list, this.searchText]
       );
   }
   // Explicit-key form (e.g. when stacking two memos in one getter)
   get pair() {
       const a = this.memo("a", () => expensiveA(), [this.list]);
       const b = this.memo("b", () => expensiveB(), [this.searchText]);
       return { a, b };
   }
   get dependencies() { return [this.dependency(this.list)]; }
}

Inherited from

ReactiveNode.memo

moveTo()#

Call Signature#

moveTo<TValue>(destination, key?): this;

Defined in: retree-core/bin/ReactiveNode.d.ts:137

Move this node to a new structural parent.

Type Parameters

Parameters

Returns

this

The latest reproxy for this node after it moves.

Remarks

This is a convenience wrapper around Retree.move. Use it from instance methods when a node should transfer ownership to another Retree-managed array, map, set, or object.

Do not call moveTo on a root node; roots have no parent to remove from. Do not manually remove the node from its current parent before moving.

Example

class Task extends ReactiveNode {
    public title = "";

    public complete(done: Task[]) {
        this.moveTo(done); // same as Retree.move(this, done)
    }
}

Inherited from

ReactiveNode.moveTo

Call Signature#

moveTo<TKey, TValue>(destination, key): this;

Defined in: retree-core/bin/ReactiveNode.d.ts:138

Move this node to a new structural parent.

Type Parameters

Parameters

Returns

this

The latest reproxy for this node after it moves.

Remarks

This is a convenience wrapper around Retree.move. Use it from instance methods when a node should transfer ownership to another Retree-managed array, map, set, or object.

Do not call moveTo on a root node; roots have no parent to remove from. Do not manually remove the node from its current parent before moving.

Example

class Task extends ReactiveNode {
    public title = "";

    public complete(done: Task[]) {
        this.moveTo(done); // same as Retree.move(this, done)
    }
}

Inherited from

ReactiveNode.moveTo

Call Signature#

moveTo<TValue>(destination): this;

Defined in: retree-core/bin/ReactiveNode.d.ts:139

Move this node to a new structural parent.

Type Parameters

Parameters

Returns

this

The latest reproxy for this node after it moves.

Remarks

This is a convenience wrapper around Retree.move. Use it from instance methods when a node should transfer ownership to another Retree-managed array, map, set, or object.

Do not call moveTo on a root node; roots have no parent to remove from. Do not manually remove the node from its current parent before moving.

Example

class Task extends ReactiveNode {
    public title = "";

    public complete(done: Task[]) {
        this.moveTo(done); // same as Retree.move(this, done)
    }
}

Inherited from

ReactiveNode.moveTo

Call Signature#

moveTo<TDestination>(destination, key): this;

Defined in: retree-core/bin/ReactiveNode.d.ts:140

Move this node to a new structural parent.

Type Parameters

Parameters

Returns

this

The latest reproxy for this node after it moves.

Remarks

This is a convenience wrapper around Retree.move. Use it from instance methods when a node should transfer ownership to another Retree-managed array, map, set, or object.

Do not call moveTo on a root node; roots have no parent to remove from. Do not manually remove the node from its current parent before moving.

Example

class Task extends ReactiveNode {
    public title = "";

    public complete(done: Task[]) {
        this.moveTo(done); // same as Retree.move(this, done)
    }
}

Inherited from

ReactiveNode.moveTo

onChanged()#

protected onChanged(): void;

Defined in: retree-query/src/QueryNode.ts:177

Runs after this ReactiveNode receives a fresh reproxy.

Returns#

void

Remarks#

Override this when a node needs to synchronize derived state only after a real Retree change. Retree runs this before nodeChanged / treeChanged listeners flush. If no transaction is already active, Retree starts one so state updates made here are batched with the reproxy that triggered the effect.

Use this for small synchronization writes that should happen only after Retree has confirmed a real change. Avoid writing unconditionally here; guard against loops by checking whether the derived value actually changed.

Example#

class SearchState extends ReactiveNode {
    public query = "";
    public normalizedQuery = "";

    protected onChanged() {
        const next = this.query.trim().toLowerCase();
        if (this.normalizedQuery !== next) {
            this.normalizedQuery = next;
        }
    }
}

Overrides#

ReactiveNode.onChanged

onObserved()#

protected onObserved(): void;

Defined in: retree-query/src/QueryNode.ts:169

Runs when this ReactiveNode gets its first active nodeChanged or treeChanged observer.

Returns#

void

Remarks#

Override this for work that requires the proxied instance, such as starting external subscriptions that write back into Retree state.

Keep setup idempotent. Retree calls this when the first active nodeChanged or treeChanged listener starts observing the node, not when the node is constructed.

Example#

class LiveValue extends ReactiveNode {
    public value = "";
    @ignore private unsubscribe: (() => void) | null = null;

    protected onObserved() {
        this.unsubscribe = subscribe((value) => {
            this.value = value; // ✅ emits through Retree
        });
    }
}

Overrides#

ReactiveNode.onObserved

onUnobserved()#

protected onUnobserved(): void;

Defined in: retree-query/src/QueryNode.ts:181

Runs when this ReactiveNode loses its last active nodeChanged or treeChanged observer.

Returns#

void

Remarks#

Use this to clean up resources created in ReactiveNode.onObserved. Do not rely on it as a destructor for unobserved nodes; it only runs after observation had started.

Example#

protected onUnobserved() {
    this.unsubscribe?.();
    this.unsubscribe = null;
}

Overrides#

ReactiveNode.onUnobserved

optimisticUpdate()#

optimisticUpdate(transform): void;

Defined in: retree-query/src/QueryNode.ts:348

Apply an optimistic update. If a mutation context is provided, rollback when its promise rejects unless a newer server value resolves the dirty state first.

Parameters#

Returns#

void

Remarks#

Use this when the UI should update immediately before the backend confirms the write. The transform mutates the existing query state in place and emits through Retree.

Prefer small, targeted transforms. Provide revert(...) when the default rollback to the last clean server value is not specific enough.

Example#

node.optimisticUpdate({
    ctx: { promise: mutationPromise },
    apply(tasks) {
        const task = tasks.find((item) => item.id === taskId);
        if (task) task.isCompleted = !task.isCompleted;
    },
});

peekInto()#

peekInto<TResult>(fn): TResult;

Defined in: retree-core/bin/ReactiveNode.d.ts:259

Run a read-only query against this node's raw object at native speed, then resolve the result back to its Retree-managed node when one exists.

Type Parameters#

Parameters#

Returns#

TResult

The callback result, resolved to its managed node when one exists.

Remarks#

This is a convenience wrapper around Retree.peekInto for this. The callback receives the raw object behind this node (ReactiveNode.raw), so reads inside it skip proxy traps and are not tracked as dependencies. If the returned value is an object that belongs to a Retree tree, the latest managed node (reproxy or base proxy) is returned instead; primitives and unmanaged objects are returned as-is.

Only the returned value itself is resolved. Containers built inside the callback (for example filter results) are returned unchanged, with raw elements. Children that have never been read through the managed tree have no proxy yet and resolve to their raw value; traverse the path once, or use prepareTree / autoPrepare, when a managed result is required.

Example#

class TaskList extends ReactiveNode {
    public tasks: Task[] = [];

    get dependencies() {
        return [this.dependency(this.tasks)];
    }

    public findTask(id: string): Task | undefined {
        // Scans raw at native speed; returns the managed task node.
        return this.peekInto((raw) =>
            raw.tasks.find((task) => task.id === id)
        );
    }
}

Inherited from#

ReactiveNode.peekInto

prepareTree()#

prepareTree(options?): void;

Defined in: retree-core/bin/ReactiveNode.d.ts:440

Prepare lazy Retree child proxies below this ReactiveNode.

Parameters#

Returns#

void

Remarks#

Retree lazily proxies plain object and array fields on ReactiveNodes. Call this when an app wants to pay that first-touch cost during a controlled phase, such as while showing a loading spinner. This walks only own data properties, so computed getters like dependencies are not evaluated or cached as child nodes. Fields marked with @ignore are skipped.

Do not call this for every render. Call it once during setup, loading, or before a known interaction that will traverse a large subtree.

Example#

class LargeNode extends ReactiveNode {
    public sections = [{ title: "Intro", cards: [] }];
}

const node = Retree.root(new LargeNode());
node.prepareTree({ depth: 1 });

Inherited from#

ReactiveNode.prepareTree

raw()#

raw(): this;

Defined in: retree-core/bin/ReactiveNode.d.ts:201

Get the raw, unproxied object behind this node for read-only, non-reactive access.

Returns#

this

The raw object behind this node.

Remarks#

This is a convenience wrapper around Retree.raw for this. Reads on the returned object skip proxy traps entirely, so algorithms that scan large collections owned by this node can run at native speed.

Treat the result as read-only: direct mutations skip Retree change emission. Reads are invisible to reactivity, including this node's own auto-trapped @memo / @select dependency collection. Throws when the node is not yet Retree-managed (for example inside the constructor, before Retree.root(...) or tree attachment).

Example#

class Leaderboard extends ReactiveNode {
    public scores: number[] = [];

    get dependencies() {
        return [this.dependency(this.scores)];
    }

    get total() {
        // Raw scan; reactivity comes from `dependencies`.
        return this.raw().scores.reduce((sum, s) => sum + s, 0);
    }
}

Inherited from#

ReactiveNode.raw

restoreState()#

protected restoreState(next): void;

Defined in: retree-query/src/QueryNode.ts:511

Write an emitted or rollback value into state.

Parameters#

Returns#

void

Remarks#

Applies the configured IStateReconciler when one exists, otherwise gives QueryNode.tryDefaultReconcile a chance before replacing the state wholesale. Subclasses with non-plain state shapes (for example paginated results carrying a loadMore function) override this.

retry()#

retry(): void;

Defined in: retree-query/src/QueryNode.ts:235

Re-subscribe to the query after result.status is "error".

Returns#

void

Remarks#

Use this from retry affordances in UI. It closes the errored subscription and opens a fresh one with the current args, moving the result to "pending" (or the cached value when the backend has one). Does nothing unless the current status is "error".

Example#

if (node.result.status === "error") {
    node.retry(); // ✅ re-opens the subscription
}

stateEquals()#

protected stateEquals(left, right): boolean;

Defined in: retree-query/src/QueryNode.ts:657

Compare an incoming emission against the last clean baseline.

Parameters#

Returns#

boolean

Remarks#

The base implementation is a deep structural compare. Subclasses whose state carries members that churn identity without meaning (such as a loadMore function) override this.

tryDefaultReconcile()#

protected tryDefaultReconcile(_next): boolean;

Defined in: retree-query/src/QueryNode.ts:547

Backend-convention reconciliation used when no explicit reconciler was configured. Return true when next was reconciled into the current state in place. The base implementation performs no reconciliation.

Parameters#

Returns#

boolean

untracked()#

untracked<T>(fn): T;

Defined in: retree-core/bin/ReactiveNode.d.ts:214

Run a synchronous function with Retree dependency tracking paused.

Type Parameters#

Parameters#

Returns#

T

The function's return value.

Remarks#

This is a convenience wrapper around Retree.untracked. Use it inside auto-trapped @memo, @fnMemo, and @select bodies when bulk reads should not become dependencies. Reads still go through Retree proxies; writes still emit normally.

Inherited from#

ReactiveNode.untracked

updateArgs()#

updateArgs(args): void;

Defined in: retree-query/src/QueryNode.ts:214

Update the query arguments and resubscribe when the arguments change (compared deeply).

Parameters#

Returns#

void

Remarks#

Use this when query args are controlled by Retree state, routing, or user input. Passing "skip" disables the active subscription and sets result.status to "skipped".

Updating args can emit because state, result, and error may change. When the node was constructed with keepPreviousData, the previous state stays visible while the new subscription loads and result.isStale is true until the first value arrives.

On a disposed node this records the new args without opening a subscription; the node resubscribes with the latest args when it is observed again.

Example#

node.updateArgs({ listId: "tomorrow" }); // ✅ may emit pending/success
node.updateArgs("skip"); // ✅ emits skipped state and unsubscribes