Validaterl is a simple Erlang library for validating (input) data.
Using records defined in validaterl/include/validaterl.hrl one can check individual values against
validators.
For example:
> validaterl:validate(1, #range{ to = 10 }) true > validaterl:validate(1, #range{ to = 0 }) greater
Also, if the second argument is not a validator, it will be matched against the first argument:
> validaterl:validate(1, 1). true > validaterl:validate(1, 2). lesser > validaterl:validate(1, 0). greater
One can define custom validators using this layout:
-record(my_validator, { '$validator' = fun mymodule:myvalidator/2, ... %% rest of arguments }).
Instead of running individual validations, you can define so called "validation sheets" and test them using
validaterl:validate/1.
Validation sheet is a list of validations in the following format:
{Name :: any(), Value :: any(), Spec :: spec()}For example:
[
{'user.name', Username, #length{ is = #range{ from = 3, to = 16 } }},
{'user.email', Email, #length{ is = #range { from = 3, to = 255 } }},
{'user.age', Age, #numericality{ allow_string = true }}
]Just as an example, if you try to put a string with a non-numeric value into Age, you'll get this:
[{'user.age',"wrong",
#numericality{'$validator' = #Fun<validaterl.validate.2>,
allow_undefined = false,allow_null = false,
allow_string = true,allow_empty = false,allow_rest = false,
allow_float = true,default = 0},
number_expected}]