ApplicationException class

Defines a base class to defive various application exceptions.

Most languages have own definition of base exception (error) types. However, this class is implemented symmetrically in all languages supported by PipServices toolkit. It allows to create portable implementations and support proper error propagation in microservices calls.

Error propagation means that when microservice implemented in one language calls microservice(s) implemented in a different language(s), errors are returned throught the entire call chain and restored in their original (or close) type.

Since number of potential exception types is endless, PipServices toolkit supports only 12 standard categories of exceptions defined in ErrorCategory. This ApplicationException class acts as a basis for all other 12 standard exception types.

Most exceptions have just free-form message that describes occured error. That may not be sufficient to create meaninful error descriptions. The ApplicationException class proposes an extended error definition that has more standard fields:

• message: is a human-readable error description
• category: one of 12 standard error categories of errors
• status: numeric HTTP status code for REST invocations
• code: a unique error code, usually defined as 'MY_ERROR_CODE'
• correlation_id: a unique transaction id to trace execution through a call chain
• details: map with error parameters that can help to recreate meaningful error description in other languages
• stack_trace: a stack trace
• cause: original error that is wrapped by this exception

ApplicationException class is not serializable. To pass errors through the wire it is converted into ErrorDescription object and restored on receiving end into identical exception type.

See ErrorCategory See ErrorDescription

Implemented types

• Exception

Implementers

• BadRequestException
• ConfigException
• ConflictException
• ConnectionException
• FileException
• InternalException
• InvalidStateException
• InvocationException
• NotFoundException
• UnauthorizedException
• UnknownException
• UnsupportedException

Constructors

ApplicationException([String? category, String? correlation_id, String? code, String? message])

Creates a new instance of application exception and assigns its values.

ApplicationException.fromJson(Map<String, dynamic> json)

factory

Properties

category ↔ String

Standard error category

getter/setter pair

cause ↔ String?

getter/setter pair

code ↔ String

A unique error code

getter/setter pair

correlation_id ↔ String?

A unique transaction id to trace execution throug call chain

getter/setter pair

details ↔ StringValueMap?

A map with additional details that can be used to restore error description in other languages

getter/setter pair

hashCode → int

The hash code for this object.

no setter, inherited

message ↔ String?

A human-readable error description (usually written in English)

getter/setter pair

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

stack_trace ↔ String?

Stack trace of the exception

getter/setter pair

status ↔ int

HTTP status code associated with this error type

getter/setter pair

Methods

fromJson(Map<String, dynamic> json) → void

getCauseString() → String?

Gets original error wrapped by this exception as a string message.

getStackTraceString() → String?

Gets a stack trace where this exception occured.

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

setCauseString(String value) → void

Sets original error wrapped by this exception as a string message.

setStackTraceString(String value) → void

Sets a stack trace where this exception occured.

toJson() → Map<String, dynamic>

toString() → String

A string representation of this object.

override

withCause(dynamic cause) → ApplicationException

Sets a original error wrapped by this exception

withCode(String code) → ApplicationException

Sets a unique error code.

withCorrelationId(String? correlationId) → ApplicationException

Sets a correlation id which can be used to trace this error through a call chain.

withDetails(String key, dynamic value) → ApplicationException

Sets a parameter for additional error details. This details can be used to restore error description in other languages.

withStackTrace(String stackTrace) → ApplicationException

Sets a stack trace for this error.

withStatus(int status) → ApplicationException

Sets a HTTP status code which shall be returned by REST calls.

wrap(dynamic cause) → ApplicationException

Wraps another exception into an application exception object.

Operators

operator ==(Object other) → bool

The equality operator.

inherited

Static Methods

unwrapError(dynamic error) → dynamic

Unwraps original exception through wrapped exception objects.

wrapError(ApplicationException error, dynamic cause) → ApplicationException

Wraps another exception into specified application exception object.