jest-json-schema-extended

An extension of the popular jest-json-schema package - JSON schema matching for jest.

Example

const {
    dateTime,
    strictObject,
    uuidType,
    numberType,
    booleanType,
    arrayOfItems,
    anyOf,
    exactly,
    stringType,
    stringTypeCanBeEmpty,
    expectToMatchSchema,
    objectWithRequiredProps,
} = require("jest-json-schema-extended")

const objectToTest = {
    id: "47bddd19-e142-45ee-8679-463be8763022",
    enabled: false,
    created: "2019-06-12T15:08:40.292Z",
    requestors: [],
    owners: [
        {
            id: 1,
            lastName: "Robson",
            firstName: "",
            additionalInfo: {
                favouriteTvShow: "The Simpsons",
                goodAtCooking: false,
                propertyThatCanHaveVaryingTypes: "Hello",
            },
        },
        {
            id: 2,
            lastName: "Haroldson",
            firstName: "Doris",
            additionalInfo: {
                favouriteTvShow: "Parks & Recreation",
                married: true,
                propertyThatCanHaveVaryingTypes: 42,
            },
        },
    ],
}

const schema = strictObject({
    id: uuidType,
    enabled: booleanType,
    created: dateTime,
    requestors: exactly([]),
    owners: arrayOfItems(
        strictObject({
            id: numberType,
            lastName: stringType,
            firstName: stringTypeCanBeEmpty,
            additionalInfo: objectWithRequiredProps({
                favouriteTvShow: stringType,
                propertyThatCanHaveVaryingTypes: anyOf([
                    stringType,
                    numberType,
                ]),
            }),
        })
    ),
})

expectToMatchSchema(objectToTest, schema)

Install

npm i --save-dev jest-json-schema-extended

Usage

• In order to be able to use expectToMatchSchema inside jest, you need to call the following inside your test file (or you place it inside a test framework setup file):

const {setup} = require("jest-json-schema-extended");
setup()

Content

objectType

Asserts that the property is an object.

stringType

Asserts that the property is a string. The string is not allowed to be empty - use stringTypeCanBeEmpty instead if emptiness is needed.

stringTypeCanBeEmpty

Asserts that the property is a string. Allows the string to be empty.

urlType

Asserts that the property is a string looking like an URL.

dateTime

Asserts that the property is a string in date-time format.

uuidType

Asserts that the property is a string looking like a UUID.

stringTypePath

Asserts that the property is a string looking like a UNIX path.

numberType

Asserts that the property is a number.

nullType

Asserts that the property holds the value null.

booleanType

Asserts that the property is a boolean.

arrayType

Asserts that the property is an array.

arrayOfObjectsType

Loosely asserts that the property is an array of objects.

expectToMatchSchema(value, schema)

Assert that a value matches a JSON schema. Prints out errors if mismatches found.

| Param | Type | Description | | --- | --- | --- | | value | Object | The JSON object or value (string, boolean etc.) to test. | | schema | Object | The JSON schema to test the object against. |

strictObject(properties, [options])

Asserts that the object contains all the properties specified - additional properties are not allowed.

| Param | Type | Description | | --- | --- | --- | | properties | Object | Asserts for any key on the object that the property exists. Example: {propOne: stringType, propTwo: numberType} | | [options] | Object | Accepts a property optionalProps which can be a list of optional properties that don't need to be present. |

objectWithRequiredProps(properties)

Asserts that the object contains all the properties specified - additional properties are allowed.

| Param | Type | Description | | --- | --- | --- | | properties | Object | Asserts for any key on the object that the property exists. Example: {propOne: stringType, propTwo: numberType} |

arrayOfItems(itemSchema, options)

Assert a JSON schema against each array item.

| Param | Type | Description | | --- | --- | --- | | itemSchema | | | | options | Object | Accepts an option property minItems which can be used to check that the array contains at least x amount of items. |

anyOf(itemSchemas)

Assert that the property is one of the provided JSON schemas.

| Param | | --- | | itemSchemas |

stringTypeMatching(regex)

Asserts that the property is a string matching the regular expression provided.

| Param | Type | | --- | --- | | regex | RegExp |

stringTypeExact(expStr)

Asserts that the property is exactly the string as specified.

| Param | Type | | --- | --- | | expStr | String |

numberTypeGreaterThan(minimum)

Asserts that the property is a number greater than the given number.

| Param | Type | | --- | --- | | minimum | Number |

numberTypeLessThan(maximum)

Asserts that the property is a number less than the given number.

| Param | Type | | --- | --- | | maximum | Number |

oneOf(valuesExpected)

Asserts that the property received is one of the values given in the array.

| Param | Type | | --- | --- | | valuesExpected | Array.<any> |

arrayTypeOfLength(length)

Asserts that the property is an array of the exactly specified length.

| Param | Type | | --- | --- | | length | Number |

exactly(valueExpected)

Asserts that the property is exactly the value as specified. Can be anything - an object, an array, a string, a boolean, ...

| Param | Type | | --- | --- | | valueExpected | any |

isJsonSchema(toBeDetermined)

Helper function to check whether the passed in object is a JSON schema or a plain object.

| Param | Type | | --- | --- | | toBeDetermined | Object |