RFJS validation show error message with key, not label - reactjs

Question

Using https://react-jsonschema-form.readthedocs.io to render a form based on a json schema I can define validation for every field. This is great and easy, the only thing I am looking for is a way to create a more meaning full validation error.
E.g.
Schema:
{
"title": "Contextualized errors",
"type": "object",
"properties": {
"firstName": {
"type": "string",
"title": "First name",
"minLength": 8,
"pattern": "\\d+"
},
}
}
This provides validation and returns an error text like:
firstName: should NOT be shorter than 8 characters
firstName: should match pattern "\d+"
I want to change this first part, into 'First name' or even translate it. How am I possible to do this?
EDIT
I assume it would be possible to define firstName as First name, which would require some 'complex' remapping with formData object to actual keys.

Answer 1

Okay, so you can define your own Validation error for that.
validate = (formData, errors) => {
if(formData.firstName.length<8){
errors.firstName.addError('First name can be of 8 or more character long') // your custom error
}
else if(formData.firstName.search(regexPattern)){
errors.firstName.addError('First name should match your given pattern')
}
return errors;
};
and then just pass this function to your Form.
<Form
...
validate={this.validate}
showErrorList={false}
.
.
.
/>