Module `message_observer`

Passive diagnostics for publications and factory-created objects.

Attach one MessageObserver through crate::core::message_bus::MessageBus::observe. Publication ranges come from the bus's existing route counters, so producers do no extra work. Ranges preserve sequence within one route, not ordering between routes. Factory hooks retain handles and Rust type names, never message payloads or created values.

Quick Reference

Item	Kind	Description
`MessageObservation`	struct	The `MessageObservation` struct identifies a contiguous range of successful publications without retaining payloads.
`MessageObservationBatch`	struct	The `MessageObservationBatch` struct carries one lossless snapshot of publication ranges since the prior drain.
`ObservedEntity`	struct	The `ObservedEntity` struct describes one factory handle and every representation created for it.
`MessageObserver`	struct	The `MessageObserver` struct provides passive publication ranges and a factory-backed entity catalog.
`MessageObservationError`	enum	The `MessageObservationError` enum explains why passive observation could not start.

Structs

`MessageObservation`

struct MessageObservation {
    // [REDACTED: Private Fields]
}

Defined in crates/byte-engine/src/core/message_observer.rs:52-56

The MessageObservation struct identifies a contiguous range of successful publications without retaining payloads.

Implementations

```
fn topic_id(self) -> usize
```
Returns the stable bus-local route identifier used by topic diagnostics.
```
fn first_sequence(self) -> u64
```
Returns the first zero-based publication sequence in this range.
```
fn count(self) -> u64
```
Returns the number of consecutive publications in this range.

Trait Implementations

`impl ArchivePointee for MessageObservation`

```
type ArchivedMetadata = ()
```

fn pointer_metadata(_: &<T as ArchivePointee>::ArchivedMetadata) -> <T as Pointee>::Metadata

`impl<ST> CastableFrom for MessageObservation`

`impl Clone for MessageObservation`

```
fn clone(&self) -> MessageObservation
```
Related: MessageObservation

`impl Copy for MessageObservation`

`impl Debug for MessageObservation`

fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result

`impl Downcast for MessageObservation`

fn into_any(self: Box<T>) -> Box<dyn Any>

fn into_any_rc(self: Rc<T>) -> Rc<dyn Any>

```
fn as_any(&self) -> &dyn Any
```

fn as_any_mut(&mut self) -> &mut dyn Any

`impl DowncastSend for MessageObservation`

fn into_any_send(self: Box<T>) -> Box<dyn Any + Send>

`impl DowncastSync for MessageObservation`

fn into_any_arc(self: Arc<T>) -> Arc<dyn Any + Sync + Send>

`impl Eq for MessageObservation`

`impl<K> Equivalent for MessageObservation`

```
fn equivalent(&self, key: &K) -> bool
```

`impl Instrument for MessageObservation`

`impl LayoutRaw for MessageObservation`

fn layout_raw(_: <T as Pointee>::Metadata) -> Result<Layout, LayoutError>

`impl<T, N1> Niching for MessageObservation`

unsafe fn is_niched(niched: *const NichedOption<T, N1>) -> bool

fn resolve_niched(out: Place<NichedOption<T, N1>>)

`impl PartialEq for MessageObservation`

fn eq(&self, other: &MessageObservation) -> bool

Related: MessageObservation

`impl Pointable for MessageObservation`

```
const ALIGN: usize
```
```
type Init = T
```

unsafe fn init(init: <T as Pointable>::Init) -> usize

unsafe fn deref<'a>(ptr: usize) -> &'a T

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

```
unsafe fn drop(ptr: usize)
```

`impl Pointee for MessageObservation`

```
type Metadata = ()
```

`impl Read for MessageObservation`

`impl StructuralPartialEq for MessageObservation`

`impl WithSubscriber for MessageObservation`

`MessageObservationBatch`

struct MessageObservationBatch {
    // [REDACTED: Private Fields]
}

Defined in crates/byte-engine/src/core/message_observer.rs:77-79

The MessageObservationBatch struct carries one lossless snapshot of publication ranges since the prior drain.

Implementations

```
fn messages(&self) -> &[MessageObservation]
```
Related: MessageObservation

Returns one range for each route that published since the prior drain.

Trait Implementations

`impl ArchivePointee for MessageObservationBatch`

```
type ArchivedMetadata = ()
```

fn pointer_metadata(_: &<T as ArchivePointee>::ArchivedMetadata) -> <T as Pointee>::Metadata

`impl<ST> CastableFrom for MessageObservationBatch`

`impl Debug for MessageObservationBatch`

fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result

`impl Downcast for MessageObservationBatch`

fn into_any(self: Box<T>) -> Box<dyn Any>

fn into_any_rc(self: Rc<T>) -> Rc<dyn Any>

```
fn as_any(&self) -> &dyn Any
```

fn as_any_mut(&mut self) -> &mut dyn Any

`impl DowncastSend for MessageObservationBatch`

fn into_any_send(self: Box<T>) -> Box<dyn Any + Send>

`impl DowncastSync for MessageObservationBatch`

fn into_any_arc(self: Arc<T>) -> Arc<dyn Any + Sync + Send>

`impl Eq for MessageObservationBatch`

`impl<K> Equivalent for MessageObservationBatch`

```
fn equivalent(&self, key: &K) -> bool
```

`impl Instrument for MessageObservationBatch`

`impl LayoutRaw for MessageObservationBatch`

fn layout_raw(_: <T as Pointee>::Metadata) -> Result<Layout, LayoutError>

`impl<T, N1> Niching for MessageObservationBatch`

unsafe fn is_niched(niched: *const NichedOption<T, N1>) -> bool

fn resolve_niched(out: Place<NichedOption<T, N1>>)

`impl PartialEq for MessageObservationBatch`

fn eq(&self, other: &MessageObservationBatch) -> bool

Related: MessageObservationBatch

`impl Pointable for MessageObservationBatch`

```
const ALIGN: usize
```
```
type Init = T
```

unsafe fn init(init: <T as Pointable>::Init) -> usize

unsafe fn deref<'a>(ptr: usize) -> &'a T

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

```
unsafe fn drop(ptr: usize)
```

`impl Pointee for MessageObservationBatch`

```
type Metadata = ()
```

`impl Read for MessageObservationBatch`

`impl StructuralPartialEq for MessageObservationBatch`

`impl WithSubscriber for MessageObservationBatch`

`ObservedEntity`

struct ObservedEntity {
    // [REDACTED: Private Fields]
}

Defined in crates/byte-engine/src/core/message_observer.rs:90-93

The ObservedEntity struct describes one factory handle and every representation created for it.

Implementations

```
fn handle(&self) -> Handle
```
Returns the stable identity shared by the entity's representations.
```
fn types(&self) -> &[&'static str]
```
Returns the Rust type names in their first-published order.

Trait Implementations

`impl ArchivePointee for ObservedEntity`

```
type ArchivedMetadata = ()
```

fn pointer_metadata(_: &<T as ArchivePointee>::ArchivedMetadata) -> <T as Pointee>::Metadata

`impl<ST> CastableFrom for ObservedEntity`

`impl Clone for ObservedEntity`

```
fn clone(&self) -> ObservedEntity
```
Related: ObservedEntity

`impl Debug for ObservedEntity`

fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result

`impl Downcast for ObservedEntity`

fn into_any(self: Box<T>) -> Box<dyn Any>

fn into_any_rc(self: Rc<T>) -> Rc<dyn Any>

```
fn as_any(&self) -> &dyn Any
```

fn as_any_mut(&mut self) -> &mut dyn Any

`impl DowncastSend for ObservedEntity`

fn into_any_send(self: Box<T>) -> Box<dyn Any + Send>

`impl DowncastSync for ObservedEntity`

fn into_any_arc(self: Arc<T>) -> Arc<dyn Any + Sync + Send>

`impl Eq for ObservedEntity`

`impl<K> Equivalent for ObservedEntity`

```
fn equivalent(&self, key: &K) -> bool
```

`impl Instrument for ObservedEntity`

`impl LayoutRaw for ObservedEntity`

fn layout_raw(_: <T as Pointee>::Metadata) -> Result<Layout, LayoutError>

`impl<T, N1> Niching for ObservedEntity`

unsafe fn is_niched(niched: *const NichedOption<T, N1>) -> bool

fn resolve_niched(out: Place<NichedOption<T, N1>>)

`impl PartialEq for ObservedEntity`

fn eq(&self, other: &ObservedEntity) -> bool

Related: ObservedEntity

`impl Pointable for ObservedEntity`

```
const ALIGN: usize
```
```
type Init = T
```

unsafe fn init(init: <T as Pointable>::Init) -> usize

unsafe fn deref<'a>(ptr: usize) -> &'a T

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

```
unsafe fn drop(ptr: usize)
```

`impl Pointee for ObservedEntity`

```
type Metadata = ()
```

`impl Read for ObservedEntity`

`impl StructuralPartialEq for ObservedEntity`

`impl WithSubscriber for ObservedEntity`

`MessageObserver`

struct MessageObserver {
    // [REDACTED: Private Fields]
}

Defined in crates/byte-engine/src/core/message_observer.rs:113-115

The MessageObserver struct provides passive publication ranges and a factory-backed entity catalog.

Drain publication ranges through Self::drain_messages. Query current factory handles through Self::entities. Neither path retains message payloads or factory-created values.

Implementations

```
fn drain_messages(&self, topics: &[TopicSnapshot]) -> MessageObservationBatch
```
Related: TopicSnapshot, MessageObservationBatch

Returns lossless publication ranges since the prior call for these topic snapshots.
```
fn entities(&self) -> Vec<ObservedEntity>
```
Related: ObservedEntity

Returns a handle-sorted snapshot of every current factory-created entity.

Trait Implementations

`impl ArchivePointee for MessageObserver`

```
type ArchivedMetadata = ()
```

fn pointer_metadata(_: &<T as ArchivePointee>::ArchivedMetadata) -> <T as Pointee>::Metadata

`impl<ST> CastableFrom for MessageObserver`

`impl Clone for MessageObserver`

```
fn clone(&self) -> MessageObserver
```
Related: MessageObserver

`impl Downcast for MessageObserver`

fn into_any(self: Box<T>) -> Box<dyn Any>

fn into_any_rc(self: Rc<T>) -> Rc<dyn Any>

```
fn as_any(&self) -> &dyn Any
```

fn as_any_mut(&mut self) -> &mut dyn Any

`impl DowncastSend for MessageObserver`

fn into_any_send(self: Box<T>) -> Box<dyn Any + Send>

`impl DowncastSync for MessageObserver`

fn into_any_arc(self: Arc<T>) -> Arc<dyn Any + Sync + Send>

`impl Instrument for MessageObserver`

`impl LayoutRaw for MessageObserver`

fn layout_raw(_: <T as Pointee>::Metadata) -> Result<Layout, LayoutError>

`impl<T, N1> Niching for MessageObserver`

unsafe fn is_niched(niched: *const NichedOption<T, N1>) -> bool

fn resolve_niched(out: Place<NichedOption<T, N1>>)

`impl Pointable for MessageObserver`

```
const ALIGN: usize
```
```
type Init = T
```

unsafe fn init(init: <T as Pointable>::Init) -> usize

unsafe fn deref<'a>(ptr: usize) -> &'a T

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

```
unsafe fn drop(ptr: usize)
```

`impl Pointee for MessageObserver`

```
type Metadata = ()
```

enum MessageObservationError {
    AlreadyAttached,
    RoutesAlreadyRegistered,
}

Defined in crates/byte-engine/src/core/message_observer.rs:26-31

The MessageObservationError enum explains why passive observation could not start.

Variants

AlreadyAttached

This bus already has its one passive observer.
RoutesAlreadyRegistered

At least one typed route was registered before observation started.

Trait Implementations

`impl ArchivePointee for MessageObservationError`

```
type ArchivedMetadata = ()
```

fn pointer_metadata(_: &<T as ArchivePointee>::ArchivedMetadata) -> <T as Pointee>::Metadata

`impl<ST> CastableFrom for MessageObservationError`

`impl Clone for MessageObservationError`

fn clone(&self) -> MessageObservationError

Related: MessageObservationError

`impl Copy for MessageObservationError`

`impl Debug for MessageObservationError`

fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result

`impl Display for MessageObservationError`

fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result

`impl Downcast for MessageObservationError`

fn into_any(self: Box<T>) -> Box<dyn Any>

fn into_any_rc(self: Rc<T>) -> Rc<dyn Any>

```
fn as_any(&self) -> &dyn Any
```

fn as_any_mut(&mut self) -> &mut dyn Any

`impl DowncastSend for MessageObservationError`

fn into_any_send(self: Box<T>) -> Box<dyn Any + Send>

`impl DowncastSync for MessageObservationError`

fn into_any_arc(self: Arc<T>) -> Arc<dyn Any + Sync + Send>

`impl Eq for MessageObservationError`

`impl<K> Equivalent for MessageObservationError`

```
fn equivalent(&self, key: &K) -> bool
```

fn layout_raw(_: <T as Pointee>::Metadata) -> Result<Layout, LayoutError>

`impl<T, N1> Niching for MessageObservationError`

unsafe fn is_niched(niched: *const NichedOption<T, N1>) -> bool

fn resolve_niched(out: Place<NichedOption<T, N1>>)

`impl PartialEq for MessageObservationError`

fn eq(&self, other: &MessageObservationError) -> bool

Related: MessageObservationError

`impl Pointable for MessageObservationError`

```
const ALIGN: usize
```
```
type Init = T
```

unsafe fn init(init: <T as Pointable>::Init) -> usize

unsafe fn deref<'a>(ptr: usize) -> &'a T

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

```
unsafe fn drop(ptr: usize)
```

`impl Pointee for MessageObservationError`

```
type Metadata = ()
```

```
fn to_string(&self) -> String
```

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