Models---------------

class Credential(models.Model):
    """Used to store various credentials for member validation."""
    document_image = models.ImageField(
        upload_to=get_upload_path(instance="instance",
                                  filename="filename.ext",
                                  path='images/credentials/'))

    PASSENGER = 'P'
    OWNER = 'O'
    CAPTAIN = 'C'
    CREDENTIAL_CHOICES = (
        (PASSENGER, 'Passenger'),
        (OWNER, 'Owner'),
        (CAPTAIN, 'Captain'),
    )

    credential_type = models.CharField(max_length=1,
                                       choices=CREDENTIAL_CHOICES,
                                       default=PASSENGER)
    credential_number = models.CharField(max_length=255)
    date_received = models.DateTimeField(auto_now_add=True)
    is_verified = models.BooleanField(default=False)
    date_verified = models.DateTimeField(blank=True)
    member = models.ForeignKey(settings.AUTH_USER_MODEL,
                                  related_name='credentials')

class MemberProfile(models.Model):
    user = models.OneToOneField(settings.AUTH_USER_MODEL, unique=True, related_name='profile')
    profile_image = models.ImageField(
            upload_to=get_upload_path(instance="instance",
                                  filename="filename",
                                  path='images/profile/'),
            blank=True)
    phone_number = models.CharField(max_length=15,
            validators=[
                validators.RegexValidator(r'^\+?1?\d{9,15}$',
                          _('Enter a valid telephone number. '
                            "Phone number must be entered in the "
                            "format: '+999999999'. Up to 15 digits"
                            " allowed."), 'invalid'),
            ],
            error_messages={
                # Wrong error message?
                'unique': _("This telephone number doesn't match our format!"),
            },
            blank=True)
    address = models.ForeignKey(Location, blank=True,
                                related_name='member_profiles')
    is_passenger = models.BooleanField(_('passenger status'), default=True,
                   help_text=_('Designates whether the member is a passenger.'))
    is_owner = models.BooleanField(_('owner status'), default=False,
                       help_text=_('Designates whether the member is a owner.'))
    is_captain = models.BooleanField(_('captain status'), default=False,
                     help_text=_('Designates whether the member is a captain.'))
    date_profile_created = models.DateTimeField(_('date profile created'),
                                                auto_now_add=True)
    date_profile_modified = models.DateTimeField(_('date profile modified'),
                                                 auto_now=True)


Serializers----------

class MemberProfileSerializer(serializers.ModelSerializer):
    class Meta:
        model = MemberProfile
        fields = (
            'profile_image',
            'phone_number',
            'is_passenger',
            'is_owner',
            'is_captain',
            'date_profile_created',
            'date_profile_modified',
        )


class CredentialSerializer(serializers.ModelSerializer):
    class Meta:
        model = Credential
        fields = (
            'credential_type',
            'credential_number',
            'date_received',
            'is_verified',
            'date_verified',
            'document_image',
        )


class AuthUserModelSerializer(serializers.ModelSerializer):
    credentials = CredentialSerializer(many=True)
    member = MemberProfileSerializer(read_only=True)

    class Meta:
        model = get_user_model()
        fields = ('id',
                  'username',
                  'password',
                  'email',
                  'first_name',
                  'last_name',
                  'is_staff',
                  'is_active',
                  'date_joined',
                  'member',
                  'credentials',
                  )