Error handling

Overview

As you might have read along these documents, most of the MobbScanAPI callbacks have an error as their last argument. This is the way MobbScan let you know the reason why a process did not end successfully.

The possible error comes with the general structure as follows:

{
    "errorCode": "WRONG_PARAMETERS_ERROR",
    "errorDetails": "Some of the parameters are not valid"
}

where:

• errorCode: is a string and represents the specific code identifying the error.
• errorDetails: is a string and provides additional information or context about the error.

Error Codes

The following table shows the possible error codes and their meaning:

Code	Meaning	Method
CONNECTION_ERROR	A network connection error happened.	startScan
DOCUMENT_NOT_CLASSIFIED	The system is not able to classify the document (see below).	scanDocument
ERROR_WRONG_DOCUMENT_TYPE	The document selected for scanning does not match the document used by the user.	scanDocument
FACE_DOCUMENT_NOT_DETECTED_ERROR	The system is not able to detect a face on the document.	scanDocument
SCAN_PROCESS_ALREADY_STARTED_ERROR	The scan process identifier (scanId) is already used.	startScan
UNAUTHORIZED_ERROR	Wrong scanId, previously used or expired token.	startScan, scanDocument, validateFace
USER_CANCELLED_ERROR	Back button pressed during the scanning process.	scanDocument, validateFace
VALIDATION_ERROR	The validation criteria were not met (see below).	scanDocument, validateFace
WRONG_PARAMETERS_ERROR	Wrong token or no scanId provided.	startScan

Document Not Classified Error

This type of error may occur when the system is unable to classify the document used by the user in the scanDocument method. In this case, the error will also include a more specific reason that can be used to provide additional information to the user, as shown in the example below.

{
    "errorCode": "DOCUMENT_NOT_CLASSIFIED",
    "errorDetails": "The system is not able to classify the document",
    "errorReason": "NOT_VALID_DOCUMENT"
}

where:

• errorReason: is a string and represents the specific reason identifying the error.

The following table shows the possible error reasons and their meaning:

Code	Meaning
ERROR_BACK_DOCUMENT_SIDE_DUPLICATED	The two images from the scanning process are of the back side of a document.
ERROR_FRONT_DOCUMENT_SIDE_DUPLICATED	The two images from the scanning process are of the front side of a document.
ERROR_DOCUMENT_SIDE_TYPE_MISMATCH	The images of the front and back sides of the document are from different types of documents.
NOT_VALID_DOCUMENT	The document has been classified but does not belong to the specified document type (for example, a German document with documentType ESP).

Validation Error

This type of error may occur when one or more validations fail in the scanDocument or validateFace methods. In this case, the error will also include the details of the failed validations, as shown in the examples below, as well as an optional specific reason in the case of the validateFace method.

scanDocument

validateFace

{
    "errorCode": "VALIDATION_ERROR",
    "errorDetails": "Some of the validation criteria have failed.",
    "failedValidations": ["validationDocumentNotExpired", "validationDocumentNotSpecimen"]
}

where:

• failedValidations: is an array of strings listing the validation criteria that have not been met.

{
    "errorCode": "VALIDATION_ERROR",
    "errorDetails": "Some of the validation criteria have failed.",
    "errorReason": "FACE_NOT_FOUND",
    "failedValidations": ["validationLiveness", "validationIdentityVerification"]
}

where:

• errorReason: is a string and represents the specific reason identifying the error.
• failedValidations: is an array of strings listing the validation criteria that have not been met.

The following table shows the possible error reasons and their meaning:

Code	Meaning
BAD_FACE_POSITION	The face is not positioned correctly for verification.
BAD_LIGHTING	Lighting conditions do not allow for proper verification.
FACE_NOT_FOUND	No valid face was detected for verification.
FACE_SERVICE_ERROR	An error occurred while communicating with the verification service.
MULTIPLE_FACES_DETECTED	Multiple faces were detected, and verification cannot be performed.
VALIDATION_MATRIX_NOT_PASSED	Some of the validation criteria have failed.