Struct DiscriminatedDocument 

#[non_exhaustive]
pub struct DiscriminatedDocument { /* private fields */ }

A Document together with an optional discriminator and optional protocol settings.

See the module-level documentation for the rationale behind splitting this off Document.

This type is #[non_exhaustive] so that future fields (e.g. a typed Schema reference, if the schema crate ever adds schema-binding to this wrapper) can land additively.

Note that this is deliberately unlike Document, which is intentionally not #[non_exhaustive]: Document is a released, exhaustively-matchable enum, and callers are expected to match it without a wildcard arm. Adding a variant to Document would be a breaking change, which is precisely why the extra context this wrapper carries lives here instead of on Document itself.

Implementations

impl DiscriminatedDocument

pub fn new(document: Document) -> Self

Creates a new DiscriminatedDocument wrapping document, with no discriminator and no settings attached.

pub fn with_discriminator(self, fqn: impl Into<String>) -> Self

Attaches a discriminator (a Smithy fully-qualified shape ID) to this document.

Used by the schema-serde pipeline when constructing a document from a typed shape: the schema’s shape_id (in its namespace#name FQN form) gets attached as the discriminator so downstream consumers (the type registry, the __type write path) know what shape the document represents.

The discriminator MUST be an absolute shape ID — the namespace#name FQN form, never a bare shape name. The SEP requires a serialized __type to always be absolute so the document stays context-free for downstream readers, and the type registry keys on the FQN. Passing a relative id is a caller error and trips a debug_assert!.

pub fn with_settings(self, settings: Arc<dyn DocumentSettings>) -> Self

Attaches protocol settings to this document.

Used by codec deserializers to plumb format-specific coercion rules through to downstream consumers of the document tree. The same Arc is cloned into nested documents so the entire tree shares one settings instance.

pub fn discriminator(&self) -> Option<&str>

Returns the discriminator, if attached.

pub fn settings(&self) -> Option<&Arc<dyn DocumentSettings>>

Returns a reference to the attached protocol settings, if any.

pub fn document(&self) -> &Document

Returns a reference to the wrapped document data.

pub fn into_document(self) -> Document

Consumes this wrapper and returns the inner document.

pub fn as_blob(&self) -> Result<Cow<'_, [u8]>, DocumentError>

Returns this document’s value as bytes.

Document has no native blob variant: the schema-driven legacy representation of a Smithy blob is a base64-encoded Document::String. This accessor therefore dispatches two ways:

• With protocol settings attached, delegates to DocumentSettings::coerce_string_to_blob.
• With no settings attached, falls back to the deterministic default: standard base64 decode.

Non-string variants return DocumentError::TypeMismatch.

pub fn as_timestamp(&self) -> Result<DateTime, DocumentError>

Returns this document’s value as a timestamp.

Document has no native timestamp variant: the schema-driven legacy representation of a Smithy timestamp is a Document::Number holding epoch seconds. This accessor dispatches four ways:

• For Document::Number with settings attached, delegates to DocumentSettings::coerce_number_to_timestamp; with no settings, falls back to the deterministic epoch-seconds default.
• For Document::String with settings attached, delegates to DocumentSettings::coerce_string_to_timestamp; with no settings, falls back to parsing RFC-3339 (date-time), which is Smithy’s default string timestamp format.

Other variants return DocumentError::TypeMismatch.

Trait Implementations

impl Clone for DiscriminatedDocument

fn clone(&self) -> DiscriminatedDocument

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for DiscriminatedDocument

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

Formats the value using the given formatter.

impl Default for DiscriminatedDocument

fn default() -> DiscriminatedDocument

Returns the “default value” for a type.

impl From<Document> for DiscriminatedDocument

fn from(document: Document) -> Self

Converts to this type from the input type.

impl PartialEq for DiscriminatedDocument

PartialEq is implemented manually to compare document and discriminator only — settings is metadata about how the document was produced (and dyn DocumentSettings doesn’t admit equality anyway).

Two discriminated documents holding the same data with different settings are considered equal: this matches the behavior of the schema-crate type that this design replaces, and matches user intent (“are these the same document?” doesn’t depend on protocol metadata).

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

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.