Module: Janeway

Defined in:
lib/janeway.rb,
lib/janeway/error.rb,
lib/janeway/lexer.rb,
lib/janeway/query.rb,
lib/janeway/token.rb,
lib/janeway/parser.rb,
lib/janeway/version.rb,
lib/janeway/ast/null.rb,
lib/janeway/ast/error.rb,
lib/janeway/functions.rb,
lib/janeway/ast/number.rb,
lib/janeway/enumerator.rb,
lib/janeway/ast/boolean.rb,
lib/janeway/ast/helpers.rb,
lib/janeway/interpreter.rb,
lib/janeway/ast/function.rb,
lib/janeway/ast/selector.rb,
lib/janeway/ast/root_node.rb,
lib/janeway/ast/expression.rb,
lib/janeway/ast/string_type.rb,
lib/janeway/functions/count.rb,
lib/janeway/functions/match.rb,
lib/janeway/functions/value.rb,
lib/janeway/normalized_path.rb,
lib/janeway/ast/current_node.rb,
lib/janeway/functions/length.rb,
lib/janeway/functions/search.rb,
lib/janeway/ast/child_segment.rb,
lib/janeway/ast/name_selector.rb,
lib/janeway/interpreters/base.rb,
lib/janeway/ast/index_selector.rb,
lib/janeway/ast/unary_operator.rb,
lib/janeway/ast/binary_operator.rb,
lib/janeway/ast/filter_selector.rb,
lib/janeway/interpreters/yielder.rb,
lib/janeway/ast/wildcard_selector.rb,
lib/janeway/ast/descendant_segment.rb,
lib/janeway/ast/array_slice_selector.rb,
lib/janeway/interpreters/tree_constructor.rb,
lib/janeway/interpreters/root_node_deleter.rb,
lib/janeway/interpreters/function_interpreter.rb,
lib/janeway/interpreters/child_segment_deleter.rb,
lib/janeway/interpreters/name_selector_deleter.rb,
lib/janeway/interpreters/root_node_interpreter.rb,
lib/janeway/interpreters/index_selector_deleter.rb,
lib/janeway/interpreters/filter_selector_deleter.rb,
lib/janeway/interpreters/current_node_interpreter.rb,
lib/janeway/interpreters/child_segment_interpreter.rb,
lib/janeway/interpreters/name_selector_interpreter.rb,
lib/janeway/interpreters/wildcard_selector_deleter.rb,
lib/janeway/interpreters/index_selector_interpreter.rb,
lib/janeway/interpreters/unary_operator_interpreter.rb,
lib/janeway/interpreters/binary_operator_interpreter.rb,
lib/janeway/interpreters/filter_selector_interpreter.rb,
lib/janeway/interpreters/array_slice_selector_deleter.rb,
lib/janeway/interpreters/wildcard_selector_interpreter.rb,
lib/janeway/interpreters/descendant_segment_interpreter.rb,
lib/janeway/interpreters/array_slice_selector_interpreter.rb

Overview

datatracker.ietf.org/doc/rfc9535/

Defined Under Namespace

Modules: AST, Functions, Interpreters, NormalizedPath Classes: Enumerator, Error, Interpreter, Lexer, Parser, Query, Token

Constant Summary collapse

OPERATORS = 
{
  and: '&&',
  array_slice_separator: ':',
  child_end: ']',
  child_start: '[',
  current_node: '@',
  descendants: '..',
  dot: '.',
  equal: '==',
  filter: '?',
  greater_than: '>',
  greater_than_or_equal: '>=',
  group_end: ')',
  group_start: '(',
  less_than: '<',
  less_than_or_equal: '<=',
  minus: '-',
  not: '!',
  not_equal: '!=',
  or: '||',
  root: '$',
  union: ',',
  wildcard: '*',
}.freeze
ONE_CHAR_LEX = 
OPERATORS.values.select { |lexeme| lexeme.size == 1 }.freeze
TWO_CHAR_LEX = 
OPERATORS.values.select { |lexeme| lexeme.size == 2 }.freeze
TWO_CHAR_LEX_FIRST = 
TWO_CHAR_LEX.map { |lexeme| lexeme[0] }.freeze
ONE_OR_TWO_CHAR_LEX = 
ONE_CHAR_LEX & TWO_CHAR_LEX.map { |str| str[0] }.freeze
WHITESPACE = 
" \t\n\r"
KEYWORD = 
%w[true false null].freeze
FUNCTIONS = 
%w[length count match search value].freeze
ALPHABET =

faster to check membership in a string than an array of char (benchmarked ruby 3.1.2)

'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
DIGITS = 
'0123456789'
NAME_FIRST =

chars that may be used as the first letter of member-name-shorthand

'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_'
VERSION = 
'0.5.0'

Class Method Summary collapse

Class Method Details

.compile(query) ⇒ Janeway::AST::Query

Compile a JSONPath query into an Abstract Syntax Tree.

This can be combined with inputs (using #enum_for) to create Enumerators.

Examples:

query = Janeway.compile('$.store.books[? length(@.title) > 20]')
long_title_books = query.enum_for(some_data).search
query.enum_for(other_data).each do |book|
  long_title_books << book
end

Parameters:

  • query (String) —

    jsonpath query

Returns:

  • (Janeway::AST::Query) 


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# File 'lib/janeway.rb', line 38

def self.compile(query)
  Janeway::Parser.parse(query)
end

.enum_for(jsonpath, data) ⇒ Janeway::Enumerator

Pair a jsonpath query with data to make an enumerator. This can be used to apply the query to the data using Enumerator module methods such as #each and #map.

Parameters:

  • jsonpath (String) —

    jsonpath query

  • data (Array, Hash) —

    input data

Returns:



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# File 'lib/janeway.rb', line 21

def self.enum_for(jsonpath, data)
  query = compile(jsonpath)
  Janeway::Enumerator.new(query, data)
end