Cannot validate json string with Jackson. about jsonschemafriend

[jimblackler]

Same problem as #4.

The issue is that the library is 'BYOP'; Bring Your Own Parser. The 'data1' and 'data2' strings will need to be parsed to objects before validation.

For example
new ObjectMapper().readValue(data1, Map.class)

Rewriting your example:

import com.fasterxml.jackson.databind.ObjectMapper;

import java.util.HashMap;
import java.util.Map;

public class Test {
  static String schemaStr = "{\n" +
      "  \"$schema\": \"http://json-schema.org/draft-07/schema#\",\n" +
      "  \"properties\": {\n" +
      "    \"name\": {\n" +
      "      \"type\": \"string\",\n" +
      "      \"minLength\": 2\n" +
      "    }\n" +
      "  }\n" +
      "}";

  static String data1 = "{\n" +
      "  \"name\": \"Bill\"\n" +
      "}\n";
  static String data2 = "{\n" +
      "  \"name\": \"\"\n" +
      "}\n";

  public static void main(String[] args) {
    try {
      ObjectMapper mapper = new ObjectMapper();
      SchemaStore schemaStore = new SchemaStore(); // Initialize a SchemaStore.

      Map map = mapper.readValue(schemaStr, HashMap.class);
      Schema schema = schemaStore.loadSchema(map);
      Validator validator = new Validator();

      // Will not throw an exception.
      validator.validate(schema, new ObjectMapper().readValue(data1, Map.class));
      // Will throw a ValidationException.
      validator.validate(schema, new ObjectMapper().readValue(data2, Map.class));
    } catch (Exception e) {
      e.printStackTrace();
    }
  }
}

I've done a bad job of making this clear, I will have a quick attempt to clarify it in the README.

The reason I've done it this way is you can make your own choice to use Jackson, GSON, org.json parser, or have data in a compatible format like JSON5 (with my usejson library) or even YAML. All these parsers have their own tradeoffs, plus you might want to integrate jsonschemafriend into an app without having a different parser forced on you. Another benefit is that you might want to validate an object before serialization; BYOP avoids an extra step.

[ziqiangai]

Thanks for your reply.
In some cases, I just want to verify that a json string meets the JSON scema standard. But the following interface makes me not know what type of parameters to pass in, and there is no description in the comments.

  public void validate(Schema schema, Object document) throws ValidationException {
    Collection<ValidationError> errors = new ArrayList<>();
    validate(schema, document, errors::add);
    if (!errors.isEmpty()) {
      throw new ListValidationException(errors);
    }
  }

I suggest adding comments to this interface to explain what type the second parameter accepts.

[jimblackler]

0.11.0 now includes entry points for JSON strings (both schema and document).

See https://github.com/jimblackler/jsonschemafriend#basic-example-using-json-strings