JSON Schema

{
    type: 'string',     // match a string
    minLength: 3,       // with minimum length 3 characters
    maxLength: 10,      // with maximum length 10 character
    pattern: '^\\w$'    // matching the regex /^\w$/
}

{
    type: 'number',         // match a number
    minimum: 0,             // with minimum value 0
    maximum: 10,            // with maximum value 10
    exclusiveMinimum: true, // exclude the min value (default: false)
    exclusiveMaximum: true, // exclude the max value (default: false)
    multipleOf: 2           // the number must be a multiple of 2
}

{
    type: 'integer',        // match an integer number
    minimum: 0,             // with minimum value 0
    maximum: 10,            // with maximum value 10
    exclusiveMinimum: true, // exclude the min value (default: false)
    exclusiveMaximum: true, // exclude the max value (default: false)
    multipleOf: 2           // the number must be a multiple of 2
}

{
    type: 'boolean'     // match a Boolean value
}

{
    type: 'object',                     // match a JavaScript object
    minProperties: 2,                   // having at least 2 properties
    maxProperties: 5,                   // and at most 5 properties
    required: ['id', 'name'],           // where `id` and `name` are required
    properties: {                       // and the properties are as follows
        id: { type: 'string' },
        name: { type: 'string' },
        price: {
            type: 'number',
            mininum: 0
        },
        available: { type: 'boolean' }
    },
    patternProperties: {                // with additional properties, where
        '^unit-\w+$': {                 // the keys match the given regular
            type: 'number',             // expression and the values are
            minimum: 0                  // numbers with minimum value of 0
        }
    },
    additionalProperties: false         // do not allow any other properties
}                                       // (default: true)

{
    type: 'object',             // match a JavaScript object
    additionalProperties: {     // with all properties containing
        type: 'string'          // string values
    }
}

{
    type: 'object',             // if `price` is defined, then
    dependencies: {             // these two must also be defined
        price: ['unitsInStock', 'quantityPerUnit']
    }
}

{
    type: 'object',
    dependencies: {                     // if `price` is defined,
        price: {                        // then the object must also
            type: 'object',             // match the specified schema
            properties: {
                unitsInStock: {
                    type: 'integer',
                    minimum: 0
                }
            }
        }
    }
}

{
    type: 'array',          // match a JavaScript array
    minItems: 1,            // with minimum 1 item
    maxItems: 5,            // and maximum 5 items
    uniqueItems: true,      // where items are unique
    items: {                // and each item is a number
        type: 'number'
    }
}

{
    type: 'array',              // match a JavaScript array
    items: [                    // containing exactly 3 items
        { type: 'string' },     // where first item is a string
        { type: 'number' },     // and second item is a number
        { type: 'boolean' }     // and third item is a Boolean value
    ]
}

{
    type: 'null'    // match a null value
}

{
    type: 'any'     // equivalent to `{}` (matches any value)
}

{
    allOf: [                    // match a number conforming to both schemas,
        {                       // i.e. a numeric value between 3 and 5
            type: 'number',
            minimum: 0,
            maximum: 5
        },
        {
            type: 'number',
            minimum: 3,
            maximum: 10
        }
    ]
}

{
    anyOf: [                    // match either a string or a number
        { type: 'string' },
        { type: 'number' }
    ]
}

{
    oneOf: [                    // match exacly one of those schemas,
        {                       // i.e. a number that is less than 3
            type: 'number',     // or greater than 5,
            maximum: 52         // but not between 3 and 5
        },
        {
            type: 'number',
            minimum: 3
        }
    ]
}

{
    not: {                  // match a value that is not a JavaScript object
        type: 'object'
    }
}

{
    type: 'array',                              // match an array containing
    items: {                                    // items that are positive
        $ref: '#/definitions/positiveInteger'   // integers
    },
    definitions: {
        positiveInteger: {
            type: 'integer',
            minimum: 0,
            exclusiveMinimum: true
        }
    }
}