Runtime type validators

Table of Contents

Where can be used #

validate http request from client (at server side)
validate http response from server (at client side)
validate data from untyped storage, for example localStorage, JSON columns in DB, etc.
validate env variables
validate CLI arguments
validate configuration files
validate data from URL (query params)

Basic validation - can validate static types at runtime (can be restricted to JSON type)
Serialisation / deserialisation - for example, TS/JS supports Date, but JSON doesn’t. So you need to do conversion in order to support it
Compatibility with other schemas - there are tools which can convert from- or to- another schemas, for example JSONSchema, OpenAPI etc
Strict or permissive mode - would object be accepted if it contains extra fields
Helpful error messages - if in case of failed validation it points what exactly went wrong or simply dismisses the input
AOT (ahead of time) - can it use type information in order to produce validation libraries or faster serialiser, deserialiser
Custom types - can user create custom types, for example type for email, instead of string

Not a full list, but rather a high level overview

typia
- Doesn’t need extra schema definition. Uses AOT to generate validators, serialisers and deserialisers directly from TypeScript types
- Supports protocol buffers
typebox
- Supports all JSON, JS, JSONSchema, but for TS discriminated unions you need to use typebox-validators
- Can use JIT (and AOT?)
ts-runtime-checks
- Uses AOT

Read more: Type System FAQ, Documentation generators