ring-jwt-middleware.result — threatgrid/ring-jwt-middleware 1.1.2

This ns provides a set of helpers to handle an abstraction similar to Either in Haskell.

The main goal is to provide a mechanism similar to the exceptions, albeit pure - without Java Exceptions.

When a function returns a Result - it either contains a result of a successful outcome or an error with a common error structure (JwtError).

The let-either macro provides a monadic syntax. Mainly:

(let-either [result-value-1 (fn-returning-a-result-1 ,,,)
             result-value-2 (fn-returning-a-result-2 ,,,)
             ,,,]
  ,,,)

if fn-returning-a-result-1 returns an error then we will not execute the rest of the let-either. And return the full result.

->err clj

(->err err-code err-description error-metas)

Inputs: [err-code :- s/Keyword err-description :- s/Str error-metas :- #:s{Any s/Any}] Returns: Result

build a Result that contain an error.

->pure clj

(->pure v)

Inputs: [v] Returns: Result

given a value build a result containing this value

<-result clj

(<-result result)

Inputs: [result :- Result] Returns: s/Any

Either returns the value or the error contained in the Result

error? clj

(error? m)

Inputs: [m :- Result] Returns: s/Bool

return true if the given result is an Error

JwtError clj

let-either clj macro

(let-either bindings & body)

To be used to handle cascading results that may depend on preceding values. If one of the function fail, we return the failed result. If all functions are successful we return the content of the body.

Result clj

A result is similar to the Either in Haskell It represent either a value or an error

result-of clj

(result-of s)

Inputs: [s]

Build a schema representing a result expecting succesful result with schema s

success? clj

(success? m)

Inputs: [m :- Result] Returns: s/Bool

return true if the given result is not an Error