livr-spec.org

What It Is

LIVR (Language Independent Validation Rules) is a language-independent specification for data validation rules, rather than a standalone SaaS product. It emphasizes describing field validation rules in a declarative structure, such as FIELD_NAME: VALIDATION_RULE. The validator receives the value to be checked, returns an error code on failure, and returns an empty string on success. Typical use cases include user input validation, configuration validation, service contract validation, and more.

Core Capabilities

In terms of functionality, LIVR supports configuring any number of rules for each field and can return errors for all fields in a single pass. Fields without declared rules are excluded, which helps enforce an input whitelist. Its rules cover common needs such as required, not_empty, string length, enums, numeric ranges, email, url, and iso_date. It also includes meta-rules such as nested_object, list_of, list_of_objects, and or, making it suitable for complex hierarchical structures. Modifiers such as trim, to_lc, to_uc, remove, and default can also change the output result.

Languages, Ecosystem, and Documentation

A key strength of LIVR is its cross-language nature. The main content lists implementations for JavaScript, Perl, PHP, Python, Erlang, Java, Ruby, Lua, Go, Swift, and more, published across ecosystems such as npm, CPAN, packagist, pypi, and rubygems. The documentation is hosted on GitBook, with sections covering core concepts, rules, type conversion, extensions, examples, contribution, and License. It also provides an online JavaScript playground and a multi-language playground. Overall, the documentation is clearly structured and well suited for developers who want to look up rules as needed.

Pricing and Open-Source Status

The source content does not mention commercial pricing, an enterprise edition, or paid support. Based on the presence of License, How to contribute, Create own Implementation, and the various language package manager implementations, LIVR appears to be more of an open specification and open-source library ecosystem. If used in enterprise projects, teams should still verify the license and maintenance status of the specific implementation library they plan to adopt.

Pros, Cons, and Best Fit

Its advantages include declarative rules, strong cross-language consistency, error codes that work well for internationalization, and simple custom rule creation. It is especially suitable for teams with multi-language backends or teams that need to share validation contracts between frontend and backend. Its limitations are that it does not provide visual management, a hosted console, or unified commercial support. Different language implementations are maintained by different people, so version consistency and project activity need to be evaluated independently.

Access from China

The crawled content does not provide information about access from mainland China, network availability, or payment methods, so this remains unknown. Since LIVR is mainly distributed through GitBook documentation and language package repositories, actual availability depends on access to GitBook, npm, pypi, and similar services. Alternatives to consider include JSON Schema, Ajv, Joi, Yup, Zod, Marshmallow, and others.