api_error_parser 0.0.3

Parsing responses from api and handling errors in the Dart/Flutter

API Parser

A library for parsing responses from api and converting error codes into messages for the user.

• API response description
• Version
• How it works
• License

API response description

It is assumed that the response will correspond to the following specifications.

Each error from server should be in next format:

• code: a unique code of an error. Used to identify error from the dictionary.
• target: some sort of error scope
• field - the error related to certain field
• common - the error related to whole request
• message (OPTIONAL): the error message for developers (use it only for debug purposes)
• source (OPTIONAL): a container for additional data. Arbitrary structure: ( field: resource object attribute name. Required if target set to field. )

Example:

{
"data": [
     {
       "id": 1,
       "userName": "Tom",
       "age": 21
     },
     {
       "id": 2,
       "userName": "Bob",
       "age": 22
     }
   ],
  "errors": [
    {
      "code": "insufficient_funds",
      "target": "common",
      "message": "Hi Nick, it seems that user has empty balance"
    },
    {
      "code": "invalid_punctuation",
      "target": "field",
      "source": {
        "field": "userPassword"
      },
      "message": "Hi Vova, it seems that the password provided is missing a punctuation character"
    },
    {
      "code": "invalid_password_confirmation",
      "target": "field",
      "source": {
        "field": "userPassword",
        "someAdditionalData": "bla bla bla"
      },
      "message": "Hi Lesha, it seems that the password and password confirmation fields do not match"
    }
  ]
 }

Version

0.0.1

How it works

The library provides ready-made interfaces for server responses to which the object passed to the parmer must correspond.

To initialize the ErrorParser, you must pass to the constructor: errorMessages:

• Map<String, E> - the key is the error code and the value of the displayed message
• defaultErrorMessage: E - message of unknown errors

Api parser description:

• parse(response: ApiParserResponse<T>) - returns ApiParserResponse in the states: success , empty or error
• getParserResponse(response: ApiResponse<T>) - parses the server response object and returns the processed result
• getErrors(errors: List<ErrorMessage>) - returns a list of processed errors
• getMessageFromCode(errorCode: String) - returns the message associated with this error code
• getMessage(errorMessage: ErrorMessage) - returns the processed error
• getFirstMessage(errors: List<ErrorMessage>) - returns the first processed error from the list

Dart

final apiParser = ApiParser({
                  CODE.ERROR_CODE: Message.ERROR_MESSAGE,
                }, Message.DEFAULT);
               
final ParserResponseEntity<UserEntity> parserResponse = apiParser.getParserResponse(serverResponse);
                             
final ApiParserResponse<UserEntity> apiParserResponse = apiParser.parse(serverResponse); 

switch (apiParserResponse.runtimeType) {
    case  ApiParserEmptyResponse: {
      //do something
      break;
    }
    case  ApiParserErrorResponse: {
      //do something
      break;
    }
    case  ApiParserSuccessResponse: {
      //do something
      break;
    }
}
                            

License

ApiParser is released under the MIT license. See LICENSE for details.