Enum ConstraintViolation

pub enum ConstraintViolation {
    Field(InvalidValue),
    Relation(InvalidRelation),
    State(InvalidState),
}

Represents a constraint violation found by some validation function.

The variants provide different details about a constraint violation. As described in the crate level documentation this crate considers 3 categories of business rules or constraints. Violations of constraints of the different categories might provide different details about the validation.

For example a field validation might provide the field name, the actual value and an example for the expected value. A constraint on the relation of a pair of fields might provide the names of the 2 fields. Stateful constraints may provide a list of parameters that might be useful to describe the reason of the constraint violation.

An implementation of a constraint should choose the most appropriate context for the kind of business rule it is implementing. Here is a table that shows the relation of the implemented context and the variant of the constraint violation type.

Context	Constraint Violation	Construction Method
FieldName	Field	invalid_value invalid_optional_value
RelatedFields	Relation	invalid_relation
State<S>	State	invalid_state

The construction methods are a convenient way to construct ConstraintViolations.

ConstraintViolation can be serialized and deserialized using the serde crate. To use the serde support the optional crate feature serde1 must be enabled.

Variants

Field(InvalidValue)

Violation of a constraint validated in the FieldName context

Relation(InvalidRelation)

Violation of a constraint validated in the RelatedField context

State(InvalidState)

Violation of a constraint validated in the State context

Trait Implementations

impl Clone for ConstraintViolation

fn clone(&self) -> ConstraintViolation

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ConstraintViolation

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for ConstraintViolation

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for ConstraintViolation

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

Formats the value using the given formatter.

impl From<InvalidRelation> for ConstraintViolation

fn from(invalid_relation: InvalidRelation) -> Self

Converts to this type from the input type.

impl From<InvalidState> for ConstraintViolation

fn from(invalid_state: InvalidState) -> Self

Converts to this type from the input type.

impl From<InvalidValue> for ConstraintViolation

fn from(invalid_value: InvalidValue) -> Self

Converts to this type from the input type.

impl PartialEq for ConstraintViolation

fn eq(&self, other: &ConstraintViolation) -> 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.

impl Serialize for ConstraintViolation

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 ConstraintViolation