const Ajv = require("ajv");
const ajv = new Ajv();

const schema = {
  type: "object",
  properties: {
    name: { type: "string" },
    age: { type: "integer" }
  },
  required: ["name", "age"]
};

const data = { name: "Ali", age: 25 };

const validate = ajv.compile(schema);
const valid = validate(data);

if (!valid) console.log(validate.errors);
else console.log("Data is valid");