Wrong validation of MultipleOfValidator

[ubergrohman]

When using json schema with multipleOf restriction

"amount": {
    "type": "number",
    "multipleOf": 0.0000001,
    "exclusiveMaximum": 1000000000000
}

and large value (for example "amount"=999999999.12345678) MultipleOfValidator uses node.doubleValue() for getting node value and looses precision. Jackson DeserializationFeature flag USE_BIG_DECIMAL_FOR_FLOATS set to true.
Expected error is "amount: must be multiple of 1.0E-7"

[ubergrohman]

Way to fix
com.networknt.schema.MultipleOfValidator.validate

public Set<ValidationMessage> validate(JsonNode node, JsonNode rootNode, String at) {
        debug(logger, node, rootNode, at);

        if (node.isNumber()) {
            double nodeValue = node.doubleValue();
            if (divisor != 0) {
                // convert to BigDecimal since double type is not accurate enough to do the division and multiple
                BigDecimal accurateDividend = node.isBigDecimal() ? node.decimalValue() : new BigDecimal(String.valueOf(nodeValue));
                BigDecimal accurateDivisor = new BigDecimal(String.valueOf(divisor));
                if (accurateDividend.divideAndRemainder(accurateDivisor)[1].abs().compareTo(BigDecimal.ZERO) > 0) {
                    return Collections.singleton(buildValidationMessage(at, "" + divisor));
                }
            }
        }

        return Collections.emptySet();
    }

[stevehu]

@ubergrohman It makes sense to convert to BigDecimal to do the calculation. Could you please submit a PR with your fix? Github gives credit where credit is due :)

[ubergrohman]

@stevehu Please review #422.