Module: Ruby::Rego::Builtins::JsonPaths

Extended by:
RegistryHelpers
Defined in:
lib/ruby/rego/builtins/json_paths.rb

Overview

JSON path projection/redaction helpers (json.filter, json.remove), matching OPA. Both take an object document and an array or set of paths; each path is a “/”-separated string (JSON-pointer escaped: ~1 is /, ~0 is ~) or an array of literal segments. A leading run of slashes in a string path is stripped before splitting (so /a/b and a/b are equivalent); the empty string is an empty path. A numeric string segment indexes into an array. A non-object document, a paths argument that is neither an array nor a set, or a path element that is neither a string nor an array yields undefined. Operations are pure structural rewrites of the parsed value (linear in the document size), so there is no unbounded cost.

json.filter keeps only the listed paths (a terminal path keeps the whole subtree; a path that descends past a scalar keeps the scalar; a non-matching child becomes an empty container). json.remove drops the listed paths (removing an array element reindexes; multiple indices under one array are removed against the original positions).

Constant Summary collapse

JSON_PATH_FUNCTIONS = 
{
  "json.filter" => { arity: 2, handler: :filter },
  "json.remove" => { arity: 2, handler: :remove }
}.freeze
ARRAY_INDEX =

A canonical non-negative array index (no leading zeros), matching how OPA renders an index back to a path segment.

/\A(?:0|[1-9]\d*)\z/

Class Method Summary collapse

Methods included from RegistryHelpers

register_configured_functions

Class Method Details

.filter(document_value, paths_value) ⇒ Hash

Parameters:

Returns:

  • (Hash) 


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# File 'lib/ruby/rego/builtins/json_paths.rb', line 50

def self.filter(document_value, paths_value)
  select(object_document(document_value, "json.filter"), path_trie(paths_value, "json.filter"))
end

.register! ⇒ Ruby::Rego::Builtins::BuiltinRegistry

Returns:



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# File 'lib/ruby/rego/builtins/json_paths.rb', line 39

def self.register!
  registry = BuiltinRegistry.instance
  register_configured_functions(registry, JSON_PATH_FUNCTIONS)
  registry
end

.remove(document_value, paths_value) ⇒ Hash

Parameters:

Returns:

  • (Hash) 


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# File 'lib/ruby/rego/builtins/json_paths.rb', line 57

def self.remove(document_value, paths_value)
  prune(object_document(document_value, "json.remove"), path_trie(paths_value, "json.remove"))
end