Quick-check

Quick-check is small Javascript library to express JSON schema directly in the code, parse and convert objects into custom classes.

Checkout the documentation.

Schema Declaration

Quick-check let us declare data schema in a readable manner that reduces the need for documentation.

const schema = new Grammar();
schema.define("team")
    .as(anObject()
        .with(aProperty("name").ofType("string"))
        .with(aProperty("members")
              .ofType(anArrayOf(eitherOf("person", "team")))));
schema.define("person")
    .as(anObject()
        .with(aProperty("firstname")
              .ofType("string")
              .withDefault("Unknown"))
        .with(aProperty("lastname").ofType("string")));

Validation

We can now check whether the data we get from JSON or YAML file adhere to our schema.

const fileContent = fs.readFileSync('./data.yaml', 'utf8');
const data = yaml.safeLoad(fileContents);
try {
    const myTeam = schema.read(data).as("team");

} catch (report) {
    console.log(report.toString());
}

Convertion

We can also equip our type definitions with convertion rules to obtain objects instance of specific home-grown classes.

schema.on("team").apply((data) => {
    return new Team(data.name, data.members);
});

schema.on("person").apply((data) => {
    return new Person(data.firstname, data.lastname);
});

const myTeam = schema.read(data).as("team");
console.log(myTeam.members[1].members[0].name);

Features

• [x] Convertion

• [ ] Validation

  • [x] Booleans

  • [ ] Integers

    • [x] even
    • [x] odd
    • [x] a multiple of
    • [x] a power of

  • [ ] Numbers

    • [x] Strictly greater than
    • [x] Greater than
    • [x] Strictly smaller than
    • [x] Smaller than
    • [x] Is positive
    • [x] Is negative
    • [ ] CloseTo

  • [x] Strings

    • [x] Not empty
    • [x] Match a given pattern
    • [x] Start with prefix
    • [x] Ends with suffix
    • [x] Has length, at least x characters
    • [x] Has length, at most x characters

  • [x] Arrays

    • [x] fixed length
    • [x] Length check (at most)
    • [x] Length check (at least)
    • [x] Uniqueness of element

  • [x] Unions

  • [ ] Enumerations