Metarules

Metarules are rules for describing more complex rules.

nested_object

Allows you to describe validation rules for a nested object.

Error code: depends on nested validators. If nested object is not a hash should return "FORMAT_ERROR"

Example:

address: { 'nested_object': {
    city: 'required',
    zip: ['required', 'positive_integer']
} }

variable_object

Allows you to describe validation rules for field that can conatain different objects.

Error code: depends on nested validators. Or "FORMAT_ERROR" in case of receiving data not suitable for validation.

Example:

product: ['required', { 'variable_object': [
    product_type, {
        material: {
            product_type: 'required',
            material_id: ['required', 'positive_integer'],
            quantity: ['required', {'min_number': 1} ],
            warehouse_id: 'positive_integer'
        },
        service: {
            product_type: 'required',
            name: ['required', {'max_length': 10} ]
        }
    }
]}]

In this example validator will look on "product_type" and depending on it will use corresponding set of rules

list_of

Allows you to describe validation rules for a list. Validation rules will be applyed for each array element.

Error code: depends on nested validators

Example:

// new syntax (introduced in v0.4)
{ product_ids: { 'list_of': 'positive_integer' }}
{ product_ids: { 'list_of': ['required',  'positive_integer'] }} // new syntax

// old syntax
{ product_ids: { 'list_of': [[ 'positive_integer' ]] }}
{ product_ids: { 'list_of': [[ 'required',  'positive_integer' ]] }}

list_of_objects

Allows you to describe validation rules for list of objects. Validation rules will be applyed for each array element.

Error code: depends on nested validators. Or "FORMAT_ERROR" in case of receiving data not suitable for validation.

Example:

products: ['required', { 'list_of_objects': [{
    product_id: ['required','positive_integer'],
    quantity: ['required', 'positive_integer']
}]}]

list_of_different_objects

Allows you to describe validation rules for list of different objects. Validation rules will be applied for each array element.

Error code: depends on nested validators. Or "FORMAT_ERROR" in case of receiving data not suitable for validation.

Example:

products: ['required', { 'list_of_different_objects': [
    product_type, {
        material: {
            product_type: 'required',
            material_id: ['required', 'positive_integer'],
            quantity: ['required', {'min_number': 1} ],
            warehouse_id: 'positive_integer'
        },
        service: {
            product_type: 'required',
            name: ['required', {'max_length': 10} ]
        }
    }
]}]

In this example validator will look on "product_type" in each object and depending on it will use corresponding set of rules

or (experimental)

The rule takes sets of other rules and applies them one after another until successful validation.

This rule simplifies alias creation. See "Aliases" section. It is a good idea to define custom error for your alias.

Errors: As we pass several sets of rules it is unclear what should validator return in case of several errors. Currenly we return the last error (this bahavior can change in future, this rule is experimental).

Examples:

"id" should be email or positive_integer:

{
    id: { or: ['email', 'positive_integer' ] }
}

Combining with other rules:

{
    id: [{ or: ['email', 'positive_integer' ] }, 'to_lc']
}

Set of rules in "or":

{
    id: { or: [['email', 'to_lc'], 'positive_integer' ] }
}

Emulate list_of_different_objects:

{
    products: {list_of: { or: [
        {nested_object: {
            product_type: ['required', {eq: 'material'}],
            material_id: ['required', 'positive_integer'],
            quantity: ['required', {'min_number': 1} ],
            warehouse_id: 'positive_integer'
        }},

        {nested_object: {
            product_type: ['required', {eq: 'service'}],
            name: ['required', {'max_length': 20} ]
        }}
    ]}}
}

is the same as

{
    order_id: ['required', 'positive_integer'],
    products: ['required', { 'list_of_different_objects': [
        product_type, {
            material: {
                product_type: 'required',
                material_id: ['required', 'positive_integer'],
                quantity: ['required', {'min_number': 1} ],
                warehouse_id: 'positive_integer'
            },
            service: {
                product_type: 'required',
                name: ['required', {'max_length': 20} ]
            }
        }
    ]}]
}

Internally there is a difference. "or" will try apply one rule after another, but "list_of_different_objects" will select only one set of rules.