Class: Philiprehberger::TypedHash::Schema

Inherits:
Object
  • Object
show all
Defined in:
lib/philiprehberger/typed_hash/schema.rb

Overview

Schema definition for a typed hash

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(strict: false) ⇒ Schema

Returns a new instance of Schema.

Parameters:

  • strict (Boolean) (defaults to: false) —

    when true, reject unknown keys



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# File 'lib/philiprehberger/typed_hash/schema.rb', line 8

def initialize(strict: false)
  @fields = {}
  @strict = strict
end

Instance Attribute Details

#fields ⇒ Hash (readonly)

Returns the field definitions.

Returns:

  • (Hash) —

    the field definitions



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# File 'lib/philiprehberger/typed_hash/schema.rb', line 17

def fields
  @fields
end

#strict ⇒ Boolean (readonly)

Returns whether unknown keys are rejected.

Returns:

  • (Boolean) —

    whether unknown keys are rejected



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# File 'lib/philiprehberger/typed_hash/schema.rb', line 14

def strict
  @strict
end

Instance Method Details

#from_json(json_str) ⇒ Instance

Deserialize a JSON string into a typed hash instance

Parameters:

  • json_str (String) —

    JSON string

Returns:



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# File 'lib/philiprehberger/typed_hash/schema.rb', line 75

def from_json(json_str)
  data = JSON.parse(json_str, symbolize_names: true)
  new(data)
end

#key(name, type, default: nil, optional: false, coerce: nil) ⇒ void

This method returns an undefined value.

Define a key with a type and options

Parameters:

  • name (Symbol) —

    the key name

  • type (Class) —

    the expected type

  • default (Object, nil) (defaults to: nil) —

    default value

  • optional (Boolean) (defaults to: false) —

    whether the key is optional

  • coerce (Proc, nil) (defaults to: nil) —

    coercion function



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# File 'lib/philiprehberger/typed_hash/schema.rb', line 27

def key(name, type, default: nil, optional: false, coerce: nil)
  @fields[name] = {
    type: type,
    default: default,
    optional: optional,
    coerce: coerce
  }
end

#keys ⇒ Array<Symbol>

Return the declared top-level key names in definition order

Only returns top-level keys — nested schemas are represented by their parent key, not by their inner fields. The returned Array is a fresh copy; mutating it does not affect the schema.

Returns:

  • (Array<Symbol>) —

    the declared top-level key names in definition order



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# File 'lib/philiprehberger/typed_hash/schema.rb', line 59

def keys
  @fields.keys
end

#nested(name, optional: false) {|schema| ... } ⇒ void

This method returns an undefined value.

Define a nested typed hash schema

Parameters:

  • name (Symbol) —

    the key name

  • optional (Boolean) (defaults to: false) —

    whether the nested schema is optional

Yields:

  • (schema) —

    block receiving a new Schema for the nested hash



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# File 'lib/philiprehberger/typed_hash/schema.rb', line 42

def nested(name, optional: false, &block)
  nested_schema = Schema.new(strict: @strict)
  nested_schema.instance_eval(&block)
  @fields[name] = {
    type: Hash,
    optional: optional,
    nested_schema: nested_schema
  }
end

#new(data = {}) ⇒ Instance

Create a new typed hash instance from data

Parameters:

  • data (Hash) (defaults to: {}) —

    the input data

Returns:



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# File 'lib/philiprehberger/typed_hash/schema.rb', line 67

def new(data = {})
  Instance.new(self, data)
end