SchemaError

A conversion or validation failed with the message details, optionally caused by the failures in cause.

Its message adds at: and the path when the path is not the root. When cause is set, the message lists the messages of cause under Caused by: instead, without the path.

The field fieldName appears more than once in the record at source.

The value at source has the wrong shape; expectation says what was expected, as in Expected a record.

The failures of conversions such as Into. ConversionFailed is the only one.

A failure described by the free text details.

Unlike the other kinds, its message renders the path with DynamicOptic#toString, as in .format or .~ for a wrapped value, rather than with DynamicOptic#toScalaString, as in .format.when[Ebook] or .wrapped.

A step of a schema migration failed at source; kind says how.

The kinds of MigrationError: PathNotFound (the path does not exist in the value), TypeMismatch (the value has the type actual where expected was required), MissingDefault (the field has no default value), TransformFailed and InvalidValue (with a reason), FieldNotFound, FieldAlreadyExists, CaseNotFound, and MandateFailed (making an optional field mandatory failed; not raised by the built-in migrations).

The ways a migration step can fail.

The record at source has no field fieldName. The message is Missing field '' at:.

One failure: a message and the path of the place where it happened.

The variant at source has no case named caseName.

The names of the product elements.

The name of the type.

Creates a Message error with the free-text message details at the root path.

Creates a MigrationError of kind CaseNotFound at path.

Creates a ConversionFailed error with the message details at the path trace.

Creates a ConversionFailed error at the root that wraps cause. Its message is contextMessage followed by the messages of cause under Caused by:, and does not show the error's own path, even after atField.

Creates a DuplicatedField error for the field fieldName that appears more than once in the record at the path trace.

Creates an ExpectationMismatch error, for a value of the wrong shape, with the message expectation at the path trace.

Creates a MigrationError of kind FieldAlreadyExists at path.

Creates a MigrationError of kind FieldNotFound at path.

Creates a MigrationError of kind InvalidValue at path.

Creates a MigrationError of kind MandateFailed at path.

Creates a Message error with the free-text message details at path, the root by default.

Creates a MigrationError of kind kind at path.

Creates a MigrationError of kind MissingDefault at path.

Creates a MissingField error for the absent field fieldName of the record at the path trace.

Creates a MigrationError of kind PathNotFound at path.

Creates a MigrationError of kind TransformFailed at path.

Creates a MigrationError of kind TypeMismatch at path.

Creates an UnknownCase error for the case caseName that the variant at the path trace does not have.

Creates an error with the message message at the root path, for a value that breaks a rule. It is the same as conversionFailed(Nil, message).

Throw it from the to function of Schema#transform, or from a smart constructor that to calls, to reject a value while decoding. The decoder keeps only the message, at a path that ends in .wrapped, the step into the transformed value: Schema#fromDynamicValue returns it as a new ConversionFailed, and the JSON codec as a new ExpectationMismatch.

final case class Title(value: String)
object Title {
 def make(value: String): Title =
   if (value.trim.nonEmpty) Title(value)
   else throw SchemaError.validationFailed("title must not be blank")

 implicit val schema: Schema[Title] = Schema[String].transform(make, _.value)
}

val title = "\"Zionomicon\"".fromJson[Title] // Right(Title(Zionomicon))
val blank = "\"  \"".fromJson[Title]
// Left(zio.blocks.schema.SchemaError: title must not be blank at: .wrapped)