Look at alternatives for class-transformer and class-validator

[TimoGlastra]

Although class-transformer and class-validator do a lot of heavy lifting in terms of (de)seralization and validation the libraries are largely unmaintained and have issues when dealing with complexer types. This issue is to create a list of alternative to these libraries so we can make a decicision whether it is worth it to change the library to something else.

Cons:

• Libraries are mostly unmaintained
• We need an if (options) in the constructor of each class
• A lot of times there's no need for a class instance, an interface that could be validated would be sufficient
• ValidateNested doesn't work nicely, especially if you have arrays of mixed types with primitive types
• The created schemas don't always reflect the correct type which results in a half-typed rest api

Options: (https://www.typescriptneedstypes.com/)

• https://github.com/gcanti/io-ts (only validation, no transformation)
• https://github.com/colinhacks/zod (only validation)
• https://github.com/deepkit/deepkit-framework/tree/master/packages/type (does it all, but requires custom ts compiler plugin to add runtime metadata)
• https://tsoa-community.github.io/docs/ -- something like this, but more general json schema instead of openapi

[TimoGlastra]

Superseded by #1489