Struct ConstraintMetadata 

pub struct ConstraintMetadata {
    pub columns: Vec<String>,
    pub description: Option<String>,
    pub custom: HashMap<String, String>,
}

Metadata associated with a constraint.

This struct provides extensible metadata that can be attached to constraints for better observability and reporting.

Fields

columns: Vec<String>

The column(s) this constraint operates on

description: Option<String>

A human-readable description of what this constraint validates

custom: HashMap<String, String>

Additional key-value pairs for custom metadata

Implementations

impl ConstraintMetadata

pub fn new() -> Self

Creates a new metadata instance with no columns.

pub fn for_column(column: impl Into<String>) -> Self

Creates metadata for a single column constraint.

pub fn for_columns<I, S>(columns: I) -> Self

where I: IntoIterator<Item = S>, S: Into<String>,

Creates metadata for a multi-column constraint.

pub fn with_description(self, description: impl Into<String>) -> Self

Sets the description.

pub fn with_custom( self, key: impl Into<String>, value: impl Into<String>, ) -> Self

Adds a custom metadata entry.

Trait Implementations

impl Clone for ConstraintMetadata

fn clone(&self) -> ConstraintMetadata

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ConstraintMetadata

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

Formats the value using the given formatter.

impl Default for ConstraintMetadata

fn default() -> ConstraintMetadata

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for ConstraintMetadata

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for ConstraintMetadata

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

where __S: Serializer,

Serialize this value into the given Serde serializer.