This package provides the same validation & transformation pipes as @nestjs/common does, but with optionality.

This means, for example, a ParseBoolOptionalPipe will validate & transform string parameters of the form "true" and "false" into proper booleans true and false but return undefined, if null or undefined is passed as input.

This is especially useful in the case of optional @Query parameters: Let's say you wanted to add some kind of optional filtering for a resource in your api, so you add a flag as a @Query parameter - using the default ParseBoolPipe will throw an error if the flag is not provided on every request.

This package addresses this exact shortcoming: using a ParseBoolOptionalPipe instead of a ParseBoolPipe will mean the validation will not fail on "no flag provided" - it will return undefined instead, building a bridge.

Exactly the same way you would use the @nestjs/common Built-in Pipes. See the official nestjs docs for further info.

Approximately 90% of the code is taken directly from @nestjs/common, I only put my own spin on their already awesome built-in pipes.

So go check them out! (If you don't know them, how did you end up here?)