Enum concordium_contracts_common::schema_json::ToJsonError

pub enum ToJsonError {
    FormatError,
    DeserialError {
        position: u32,
        schema: Type,
        reason: String,
        data: ToJsonErrorData,
    },
    TraceError {
        position: u32,
        schema: Type,
        error: Box<ToJsonError>,
    },
}

Represents errors occurring while deserializing to the schema JSON format.

Examples

Simple type from invalid byte sequence

let account_bytes = [0u8; ACCOUNT_ADDRESS_SIZE];
let mut cursor = Cursor::new(&account_bytes[..30]); // Malformed account address
let schema = Type::AccountAddress;
let err = schema.to_json(&mut cursor).expect_err("Deserializing should fail");

assert!(matches!(err, ToJsonError::DeserialError {
    position: 0,
    schema: Type::AccountAddress,
    ..
}))

Complex type from invalid byte sequence

let account_bytes = [0u8; ACCOUNT_ADDRESS_SIZE];
let mut list_bytes = vec![2, 0]; // 2 items in the list
list_bytes.extend_from_slice(&account_bytes); // Correct account address
list_bytes.extend_from_slice(&account_bytes[..30]); // Malformed account address

let mut cursor = Cursor::new(list_bytes);
let schema = Type::List(SizeLength::U8, Box::new(Type::AccountAddress));
let err = schema.to_json(&mut cursor).expect_err("Deserializing should fail");

assert!(matches!(
   err,
   ToJsonError::TraceError {
       position: 0,
       schema: Type::List(_, _),
       error,
   } if matches!(
       *error,
       ToJsonError::DeserialError {
           position: 33,
           schema: Type::AccountAddress, ..
       }
   )
))

Variants

FormatError

JSON formatter failed to represent value.

DeserialError

Fields

position: u32

schema: Type

reason: String

data: ToJsonErrorData

Failed to deserialize data to type expected from schema.

TraceError

Fields

position: u32

schema: Type

error: Box<ToJsonError>

Trace leading to the original ToJsonError.

Implementations

impl ToJsonError

pub fn display(&self, verbose: bool) -> String

Returns a formatted error message for variant. ToJsonError::TraceError supports printing a verbose form including a more detailed description of the error stack, which is returned if verbose is set to true.

Examples

Display error from failing to deserialize to list of objects

let account_bytes = [0u8; ACCOUNT_ADDRESS_SIZE];
let contract_bytes = [0u8; 16];
let mut list_bytes = vec![2, 0];
list_bytes.extend_from_slice(&account_bytes);
list_bytes.extend_from_slice(&contract_bytes);
// r#"<error-message>
// In deserializing position <cursor-position> into type Struct(...)
// In deserializing position <cursor-position> into type List(...)"#;
list_bytes.extend_from_slice(&account_bytes);
list_bytes.extend_from_slice(&contract_bytes[..10]); // Malformed contract address.
let mut cursor = Cursor::new(list_bytes.clone());
let schema_object = Type::Struct(Fields::Named(vec![
    ("a".into(), Type::AccountAddress),
    ("b".into(), Type::ContractAddress),
]));
let schema = Type::List(SizeLength::U8, Box::new(schema_object));
let err = schema.to_json(&mut cursor)
                .expect_err("Deserializing should fail");

// The error format points to the position in the byte sequence that
// failed to deserialize:
err.display(false); // "List(...) -> Struct(...) -> <error-message>");

// Or if verbose, includes a stacktrace-like format, similar to:
// r#"<error-message>
// In deserializing position <cursor-position> into type Struct(...)
// In deserializing position <cursor-position> into type List(...)"#;
err.display(true);

pub fn get_error(&self) -> &Self

Gets the underlying error of a ToJsonError::TraceError. For any other variant, this simply returns the error itself.

Trait Implementations

impl Clone for ToJsonError

fn clone(&self) -> ToJsonError

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for ToJsonError

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

Formats the value using the given formatter.

impl Display for ToJsonError

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

Formats the value using the given formatter.

impl Error for ToJsonError

fn source(&self) -> Option<&(dyn Error + 'static)>

The lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0: use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0: replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type based access to context intended for error reports.