Class: JSI::Schema

Inherits:
Object
  • Object
show all
Includes:
FingerprintHash, Memoize
Defined in:
lib/jsi/schema.rb

Overview

JSI::Schema represents a JSON Schema. initialized from a Hash-like schema object, JSI::Schema is a relatively simple class to abstract useful methods applied to a JSON Schema.

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods included from FingerprintHash

#==, #hash

Methods included from Memoize

#clear_memo, #memoize

Constructor Details

#initialize(schema_object) ⇒ Schema

initializes a schema from a given JSI::Base, JSI::JSON::Node, or hash. Boolean schemas are instantiated as their equivalent hash ({} for true and => {} for false).

Parameters:

  • schema_object (JSI::Base, #to_hash, Boolean) —

    the schema



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# File 'lib/jsi/schema.rb', line 27

def initialize(schema_object)
  if schema_object.is_a?(JSI::Schema)
    raise(TypeError, "will not instantiate Schema from another Schema: #{schema_object.pretty_inspect.chomp}")
  elsif schema_object.is_a?(JSI::PathedNode)
    @schema_node = JSI.deep_stringify_symbol_keys(schema_object.deref)
  elsif schema_object.respond_to?(:to_hash)
    @schema_node = JSI::JSON::Node.new_doc(JSI.deep_stringify_symbol_keys(schema_object))
  elsif schema_object == true
    @schema_node = JSI::JSON::Node.new_doc({})
  elsif schema_object == false
    @schema_node = JSI::JSON::Node.new_doc({"not" => {}})
  else
    raise(TypeError, "cannot instantiate Schema from: #{schema_object.pretty_inspect.chomp}")
  end
end

Instance Attribute Details

#schema_node ⇒ JSI::PathedNode (readonly) Also known as: schema_object

Returns a JSI::PathedNode (JSI::JSON::Node or JSI::Base) for the schema.

Returns:

  • (JSI::PathedNode) —

    a JSI::PathedNode (JSI::JSON::Node or JSI::Base) for the schema



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# File 'lib/jsi/schema.rb', line 44

def schema_node
  @schema_node
end

Class Method Details

.from_object(schema_object) ⇒ JSI::Schema

Parameters:

  • schema_object (#to_hash, Boolean, JSI::Schema) —

    an object to be instantiated as a schema. if it's already a schema, it is returned as-is.

Returns:



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# File 'lib/jsi/schema.rb', line 14

def from_object(schema_object)
  if schema_object.is_a?(Schema)
    schema_object
  else
    new(schema_object)
  end
end

Instance Method Details

#[](property_name) ⇒ JSI::Base, ...

Returns property value from the schema_object.

Parameters:

  • property_name (String, Object) —

    property name to access from the schema_object

Returns:



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# File 'lib/jsi/schema.rb', line 50

def [](property_name)
  schema_object[property_name]
end

#as_json(*opt) ⇒ Object

Returns a jsonifiable representation of this schema

Returns:

  • (Object) —

    returns a jsonifiable representation of this schema



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# File 'lib/jsi/schema.rb', line 301

def as_json(*opt)
  Typelike.as_json(schema_object, *opt)
end

#default_value ⇒ Object 



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# File 'lib/jsi/schema.rb', line 218

def default_value
  if schema_node.key?('default')
    if schema_node['default'].respond_to?(:to_ary) || schema_node['default'].respond_to?(:to_hash)
      schema_class.new(schema_node['default'])
    else
      schema_node['default']
    end
  else
    nil
  end
end

#default_value? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/jsi/schema.rb', line 230

def default_value?
  schema_node.key?('default')
end

#described_object_property_names ⇒ Set

Returns any object property names this schema indicates may be present on its instances. this includes, if present: keys of this schema's "properties" object; entries of this schema's array of "required" property keys. if this schema has oneOf/allOf/anyOf subschemas, those schemas are checked (recursively) for their described object property names.

Returns:

  • (Set) —

    any object property names this schema indicates may be present on its instances. this includes, if present: keys of this schema's "properties" object; entries of this schema's array of "required" property keys. if this schema has oneOf/allOf/anyOf subschemas, those schemas are checked (recursively) for their described object property names.



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# File 'lib/jsi/schema.rb', line 198

def described_object_property_names
  memoize(:described_object_property_names) do
    Set.new.tap do |property_names|
      if schema_node['properties'].respond_to?(:to_hash)
        property_names.merge(schema_node['properties'].keys)
      end
      if schema_node['required'].respond_to?(:to_ary)
        property_names.merge(schema_node['required'].to_ary)
      end
      # we _could_ look at the properties of 'default' and each 'enum' but ... nah.
      # we should look at dependencies (TODO).
      %w(oneOf allOf anyOf).select { |k| schema_node[k].respond_to?(:to_ary) }.each do |schemas_key|
        schema_node[schemas_key].map(&:deref).map do |someof_node|
          property_names.merge(self.class.new(someof_node).described_object_property_names)
        end
      end
    end
  end
end

#fingerprint ⇒ Object

Returns an opaque fingerprint of this Schema for FingerprintHash.

Returns:

  • (Object) —

    an opaque fingerprint of this Schema for FingerprintHash



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# File 'lib/jsi/schema.rb', line 306

def fingerprint
  {class: self.class, schema_ptr: schema_node.node_ptr, schema_document: JSI::Typelike.as_json(schema_node.node_document)}
end

#fully_validate_instance(other_instance) ⇒ Array<String>

Returns array of schema validation error messages for the given instance against this schema.

Returns:

  • (Array<String>) —

    array of schema validation error messages for the given instance against this schema



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# File 'lib/jsi/schema.rb', line 236

def fully_validate_instance(other_instance)
  ::JSON::Validator.fully_validate(JSI::Typelike.as_json(schema_node.node_document), JSI::Typelike.as_json(other_instance), fragment: schema_node.node_ptr.fragment)
end

#fully_validate_schema ⇒ Array<String>

Returns array of schema validation error messages for this schema, validated against its metaschema. a default metaschema is assumed if the schema does not specify a $schema.

Returns:

  • (Array<String>) —

    array of schema validation error messages for this schema, validated against its metaschema. a default metaschema is assumed if the schema does not specify a $schema.



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# File 'lib/jsi/schema.rb', line 256

def fully_validate_schema
  ::JSON::Validator.fully_validate(JSI::Typelike.as_json(schema_node.node_document), [], fragment: schema_node.node_ptr.fragment, validate_schema: true, list: true)
end

#inspect ⇒ String Also known as: to_s

Returns a string representing this Schema.

Returns:

  • (String) —

    a string representing this Schema



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# File 'lib/jsi/schema.rb', line 279

def inspect
  "\#<#{self.class.inspect} #{object_group_text} #{schema_object.inspect}>"
end

#jsi_schema_class ⇒ Class subclassing JSI::Base Also known as: schema_class

Returns shortcut for JSI.class_for_schema(schema).

Returns:

  • (Class subclassing JSI::Base) —

    shortcut for JSI.class_for_schema(schema)



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# File 'lib/jsi/schema.rb', line 111

def jsi_schema_class
  JSI.class_for_schema(self)
end

#match_to_instance(other_instance) ⇒ JSI::Schema

if this schema is a oneOf, allOf, anyOf schema, #match_to_instance finds one of the subschemas that matches the given instance and returns it. if there are no matching *Of schemas, this schema is returned.

Parameters:

  • other_instance (Object) —

    the instance to which to attempt to match *Of subschemas

Returns:

  • (JSI::Schema) —

    a matched subschema, or this schema (self)



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# File 'lib/jsi/schema.rb', line 131

def match_to_instance(other_instance)
  # matching oneOf is good here. one schema for one instance.
  # matching anyOf is okay. there could be more than one schema matched. it's often just one. if more
  #   than one is a match, you just get the first one.
  %w(oneOf anyOf).select { |k| schema_node[k].respond_to?(:to_ary) }.each do |someof_key|
    schema_node[someof_key].map(&:deref).map do |someof_node|
      someof_schema = self.class.new(someof_node)
      if someof_schema.validate_instance(other_instance)
        return someof_schema.match_to_instance(other_instance)
      end
    end
  end
  return self
end

#new_jsi(other_instance, *a, &b) ⇒ JSI::Base

calls #new on the class for this schema with the given arguments. for parameters, see JSI::Base#initialize documentation.

Returns:

  • (JSI::Base) —

    a JSI whose schema is this schema and whose instance is the given instance



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# File 'lib/jsi/schema.rb', line 121

def new_jsi(other_instance, *a, &b)
  jsi_schema_class.new(other_instance, *a, &b)
end

#object_group_text ⇒ String

Returns a string for #instance and #pretty_print including the schema_id.

Returns:

  • (String) —

    a string for #instance and #pretty_print including the schema_id



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# File 'lib/jsi/schema.rb', line 274

def object_group_text
  "schema_id=#{schema_id}"
end

#pretty_print(q) ⇒ void

This method returns an undefined value.

pretty-prints a representation this Schema to the given printer



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# File 'lib/jsi/schema.rb', line 286

def pretty_print(q)
  q.instance_exec(self) do |obj|
    text "\#<#{obj.class.inspect} #{obj.object_group_text}"
    group_sub {
      nest(2) {
        breakable ' '
        pp obj.schema_object
      }
    }
    breakable ''
    text '>'
  end
end

#schema_id ⇒ String

Returns an absolute id for the schema, with a json pointer fragment.

Returns:

  • (String) —

    an absolute id for the schema, with a json pointer fragment



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# File 'lib/jsi/schema.rb', line 55

def schema_id
  @schema_id ||= begin
    # start from schema_node and ascend parents looking for an 'id' property.
    # append a fragment to that id (appending to an existing fragment if there
    # is one) consisting of the path from that parent to our schema_node.
    node_for_id = schema_node
    path_from_id_node = []
    done = false

    while !done
      # TODO: track what parents are schemas. somehow.
      # look at 'id' if node_for_id is a schema, or the document root.
      # decide whether to look at '$id' for all parent nodes or also just schemas.
      if node_for_id.respond_to?(:to_hash)
        if node_for_id.node_ptr.root? || node_for_id.object_id == schema_node.object_id
          # I'm only looking at 'id' for the document root and the schema node
          # until I track what parents are schemas.
          parent_id = node_for_id['$id'] || node_for_id['id']
        else
          # will look at '$id' everywhere since it is less likely to show up outside schemas than
          # 'id', but it will be better to only look at parents that are schemas for this too.
          parent_id = node_for_id['$id']
        end
      end

      if parent_id || node_for_id.node_ptr.root?
        done = true
      else
        path_from_id_node.unshift(node_for_id.node_ptr.reference_tokens.last)
        node_for_id = node_for_id.parent_node
      end
    end
    if parent_id
      parent_auri = Addressable::URI.parse(parent_id)
    else
      node_for_id = schema_node.document_root_node
      validator = ::JSON::Validator.new(Typelike.as_json(node_for_id), nil)
      # TODO not good instance_exec'ing into another library's ivars
      parent_auri = validator.instance_exec { @base_schema }.uri
    end
    if parent_auri.fragment
      # add onto the fragment
      parent_id_path = JSI::JSON::Pointer.from_fragment('#' + parent_auri.fragment).reference_tokens
      path_from_id_node = parent_id_path + path_from_id_node
      parent_auri.fragment = nil
    #else: no fragment so parent_id good as is
    end

    fragment = JSI::JSON::Pointer.new(path_from_id_node).fragment
    schema_id = parent_auri.to_s + fragment

    schema_id
  end
end

#subschema_for_index(index_) ⇒ JSI::Schema?

Returns a subschema from items or additionalItems for the given index.

Parameters:

  • index_ (Integer) —

    the index for which to find a subschema

Returns:

  • (JSI::Schema, nil) —

    a subschema from items or additionalItems for the given index



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# File 'lib/jsi/schema.rb', line 176

def subschema_for_index(index_)
  memoize(:subschema_for_index, index_) do |index|
    if schema_object['items'].respond_to?(:to_ary)
      if index < schema_object['items'].size
        self.class.new(schema_object['items'][index])
      elsif schema_object['additionalItems'].respond_to?(:to_hash)
        self.class.new(schema_object['additionalItems'])
      end
    elsif schema_object['items'].respond_to?(:to_hash)
      self.class.new(schema_object['items'])
    else
      nil
    end
  end
end

#subschema_for_property(property_name_) ⇒ JSI::Schema?

Returns a subschema from properties, patternProperties, or additionalProperties for the given property_name.

Parameters:

  • property_name_ (String) —

    the property for which to find a subschema

Returns:

  • (JSI::Schema, nil) —

    a subschema from properties, patternProperties, or additionalProperties for the given property_name



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# File 'lib/jsi/schema.rb', line 150

def subschema_for_property(property_name_)
  memoize(:subschema_for_property, property_name_) do |property_name|
    if schema_object['properties'].respond_to?(:to_hash) && schema_object['properties'][property_name].respond_to?(:to_hash)
      self.class.new(schema_object['properties'][property_name])
    else
      if schema_object['patternProperties'].respond_to?(:to_hash)
        _, pattern_schema_object = schema_object['patternProperties'].detect do |pattern, _|
          property_name.to_s =~ Regexp.new(pattern) # TODO map pattern to ruby syntax
        end
      end
      if pattern_schema_object
        self.class.new(pattern_schema_object)
      else
        if schema_object['additionalProperties'].respond_to?(:to_hash)
          self.class.new(schema_object['additionalProperties'])
        else
          nil
        end
      end
    end
  end
end

#validate_instance(other_instance) ⇒ true, false

Returns whether the given instance validates against this schema.

Returns:

  • (true, false) —

    whether the given instance validates against this schema



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# File 'lib/jsi/schema.rb', line 241

def validate_instance(other_instance)
  ::JSON::Validator.validate(JSI::Typelike.as_json(schema_node.node_document), JSI::Typelike.as_json(other_instance), fragment: schema_node.node_ptr.fragment)
end

#validate_instance!(other_instance) ⇒ true

Returns if this method does not raise, it returns true to indicate the instance is valid against this schema.

Returns:

  • (true) —

    if this method does not raise, it returns true to indicate the instance is valid against this schema

Raises:

  • (::JSON::Schema::ValidationError) —

    raises if the instance has validation errors against this schema



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# File 'lib/jsi/schema.rb', line 249

def validate_instance!(other_instance)
  ::JSON::Validator.validate!(JSI::Typelike.as_json(schema_node.node_document), JSI::Typelike.as_json(other_instance), fragment: schema_node.node_ptr.fragment)
end

#validate_schema ⇒ true, false

Returns whether this schema validates against its metaschema.

Returns:

  • (true, false) —

    whether this schema validates against its metaschema



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# File 'lib/jsi/schema.rb', line 261

def validate_schema
  ::JSON::Validator.validate(JSI::Typelike.as_json(schema_node.node_document), [], fragment: schema_node.node_ptr.fragment, validate_schema: true, list: true)
end

#validate_schema! ⇒ true

Returns if this method does not raise, it returns true to indicate this schema is valid against its metaschema.

Returns:

  • (true) —

    if this method does not raise, it returns true to indicate this schema is valid against its metaschema

Raises:

  • (::JSON::Schema::ValidationError) —

    raises if this schema has validation errors against its metaschema



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# File 'lib/jsi/schema.rb', line 269

def validate_schema!
  ::JSON::Validator.validate!(JSI::Typelike.as_json(schema_node.node_document), [], fragment: schema_node.node_ptr.fragment, validate_schema: true, list: true)
end