ata-validator-crystal

Crystal bindings for ata-validator — a high-performance C++20 JSON Schema validator.

The C++ core uses simdjson and the RE2 regex engine; this shard only wraps its pure C API (ata_c.h). Struct layouts and function signatures match ata_c.h exactly.

Install

Add to shard.yml:

dependencies:
  ata-validator-crystal:
    github: groophylifefor/ata-validator-crystal
    version: ~> 0.1.0

shards install

Native library

Two parts are required:

• ata.lib (or libata.a) — at link time, passed to crystal build via /LIBPATH (Windows/MSVC) or -L (Unix)
• ata.dll (or libata.so) — at runtime, next to the executable, on PATH, or pointed to by ATA_VALIDATOR_LIB

To build the library into libata/ (the ata-validator source must be a sibling directory):

crystal run scripts/build_native.cr

This script compiles the shared library in ata-validator with CMake and copies libata/ata.dll + libata/ata.lib into the package root. (Default source path is ../../ata-validator; override with the ATA_VALIDATOR_SRC env var.)

Build

Windows (MSVC linker):

crystal build src/main.cr --link-flags "/LIBPATH:ata-validator-crystal/libata"

Linux/macOS:

crystal build src/main.cr --link-flags "-Lata-validator-crystal/libata -lata"

Usage

require "ata-validator-crystal"

schema = <<-JSON
{
  "type": "object",
  "properties": {
    "name": {"type": "string", "minLength": 1},
    "age":  {"type": "integer", "minimum": 0}
  },
  "required": ["name"]
}
JSON

puts "ata v#{AtaValidator.version}"

# Reuse a compiled schema
validator = AtaValidator::Validator.new(schema)

result = validator.validate(%({"name": "Mert", "age": 28}))
puts result.valid                          # => true

result = validator.validate(%({"age": -1}))
puts result.valid                          # => false
result.errors.each do |e|
  puts "#{e.path}: #{e.message}"           # => /age: value -1.000000 < minimum 0.000000
end

validator.valid?(%({"name": "Mert"}))      # => true (quick boolean check)
validator.close

# One-shot (compiles the schema on every call)
AtaValidator.validate(schema, %({"name": "Mert"})).valid

API

• AtaValidator.version : String
• AtaValidator::Validator.new(schema_json) — compiles the schema once
  • validate(json) : ValidationResult (valid + errors)
  • valid?(json) : Bool
  • close / finalize — frees the compiled schema
• AtaValidator.validate(schema_json, json) : ValidationResult — one-shot
• Error types: CompileError (invalid schema), ValidationError (path, message)

Test

crystal run scripts/build_native.cr
crystal spec --link-flags "/LIBPATH:libata"

License

MIT. The C++ core comes from ata-validator, MIT licensed (original copyright preserved in LICENSE).