Struct AssertionMetadata 

pub struct AssertionMetadata { /* private fields */ }

The AssertionMetadata structure can be used as part of other assertions or on its own to reference others

Implementations

impl AssertionMetadata

pub const LABEL: &'static str = labels::ASSERTION_METADATA

Label prefix for an assertion metadata assertion.

See Metadata About Assertions - C2PA Technical Specification.

pub fn new() -> Self

pub fn reviews(&self) -> Option<&[ReviewRating]>

Returns the list of ReviewRating for this assertion if it exists.

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

Returns the ISO 8601 date-time string when the assertion was created/generated.

pub fn localizations( &self, ) -> Option<&Vec<HashMap<String, HashMap<String, String>>>>

Returns the vec of localizations maps if they exist.

pub fn data_source(&self) -> Option<&DataSource>

Returns the DataSource for this assertion if it exists.

pub fn region_of_interest(&self) -> Option<&RegionOfInterest>

Returns the RegionOfInterest for this assertion if it exists.

pub fn add_review(self, review: ReviewRating) -> Self

Adds a ReviewRating associated with the assertion.

pub fn set_reviews(self, reviews: Vec<ReviewRating>) -> Self

Sets the list of ReviewRatings associated with the assertion.

This replaces any previous list.

pub fn set_date_time(self, date_time: String) -> Self

Sets the ISO 8601 date-time string when the assertion was created/generated.

pub fn set_data_source(self, data_source: DataSource) -> Self

Sets a description of the source of the assertion data, selected from a predefined list.

pub fn set_region_of_interest( self, region_of_interest: RegionOfInterest, ) -> Self

Sets the region of interest.

pub fn set_localizations( self, localizations: Vec<HashMap<String, HashMap<String, String>>>, ) -> Self

Sets all localizations, replacing any existing ones

pub fn set_field<S: Into<String>>(self, key: S, value: Value) -> Self

Sets an arbitrary key/value pair in the metadata.

This allows adding custom fields that are not part of the standard schema, as permitted by the C2PA specification.

Arguments

• key - The key for the custom field
• value - The value as a serde_json::Value

Example

use c2pa::assertions::AssertionMetadata;
use serde_json::json;

let metadata = AssertionMetadata::new()
    .set_field("customKey", json!("customValue"))
    .set_field("nestedObject", json!({"foo": "bar", "count": 42}));

pub fn get_field(&self, key: &str) -> Option<&Value>

Gets an arbitrary key/value pair from the metadata.

Returns None if the key doesn’t exist.

Arguments

• key - The key to look up

pub fn additional_fields(&self) -> &HashMap<String, Value>

Returns a reference to all additional fields.

pub fn set_additional_fields(self, fields: HashMap<String, Value>) -> Self

Sets multiple arbitrary key/value pairs at once, replacing any existing ones.

Arguments

• fields - A HashMap of key/value pairs to set

Trait Implementations

impl Clone for AssertionMetadata

fn clone(&self) -> AssertionMetadata

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for AssertionMetadata

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

Formats the value using the given formatter.

impl Default for AssertionMetadata

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for AssertionMetadata

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for AssertionMetadata

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

Formats the value using the given formatter.

impl JsonSchema for AssertionMetadata

Available on crate feature json_schema only.

fn schema_name() -> Cow<'static, str>

The name of the generated JSON Schema.

fn schema_id() -> Cow<'static, str>

Returns a string that uniquely identifies the schema produced by this type.

fn json_schema(generator: &mut SchemaGenerator) -> Schema

Generates a JSON Schema for this type.

fn inline_schema() -> bool

Whether JSON Schemas generated for this type should be included directly in parent schemas, rather than being re-used where possible using the $ref keyword.

impl PartialEq for AssertionMetadata

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for AssertionMetadata

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for AssertionMetadata