Veli v0.1.0

View Source Veli (Veli v0.1.0)

Veli (Validation in elixir) is a simple validation library for elixir.

rule

 Rule

Rule is a keyword list that contains some rules for validation.

A rule has these options:

  • type: for validating types / affects some other rules like min and max. Supports following types:
    • string
    • integer
    • number
    • bool
    • list
    • map
  • min: Minimum value to accept.
    • for number and integer, it checks the number.
    • for string, it checks string length.
    • for list, it checks list length.
    • for map, it checks key length.
  • max: Same with min rule but for maximum values.
  • match: For matching a value.
    • for string, it uses regex to match.
    • for any other type, it will just compare both values.
  • run: Allows you to add custom filtering function inside it that returns a boolean. If it returns false, validation will fail.

Here is an example for rule defination.

username_rule = [type: :string, min: 3, max: 32, match: ~r/^[a-zA-Z0-9_]*$/]

And for validating forms:

form_rules = %{
  "username" => [type: :string, min: 3, max: 32, match: ~r/^[a-zA-Z0-9_]*$/],
  "age" => [type: :integer, min: 13]
}

Link to this section Summary

Functions

get_error(result)

An helper function for validate_form/2 that finds first error from form validation result.

validate(value, rule)

Validate a value with rule.

validate_form(form, rules)

Validate a form with rules.

validate_list(list, rule)

Validate list elements with a rule

Link to this section Functions

Link to this function

get_error(result)

View Source 
@spec get_error(list()) :: tuple() | nil

An helper function for validate_form/2 that finds first error from form validation result.

Returns first error from form validation result. nil if success.

example

 Example 

iex(1)> form = %{"username" => "james", "age" => 10}
%{"age" => 10, "username" => "james"}
iex(2)> rules = %{"username" => [type: :string], "age" => [type: :integer, min: 13]}
%{
  "age" => [type: :integer, min: 13],
  "username" => [type: :string]
}
iex(3)> Veli.validate_form(form, rules)
[{"age", :min_error}, {"username", :ok}]
iex(4)> Veli.validate_form(form, rules) |> Veli.get_error()
{"age", :min_error}
iex(5)> form = %{form | "age" => 20}
%{"age" => 20, "username" => "james"}
iex(6)> Veli.validate_form(form, rules) |> Veli.get_error()
nil
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validate(value, rule)

View Source 
@spec validate(
  any(),
  keyword()
) :: :match_error | :max_error | :min_error | :ok | :type_error

Validate a value with rule.

Returns an atom.

examples

 Examples

Simple usage

iex(1)> rule = [type: :integer, max: 100]
[type: :integer, max: 100]
iex(2)> Veli.validate(96, rule)
:ok
iex(3)> Veli.validate(101, rule)
:max_error

Adding custom filtering functions

iex(1)> rule = [type: :string, run: fn value -> String.reverse(value) === value end]
[type: :string, run: #Function<42.3316493/1 in :erl_eval.expr/6>]
iex(2)> Veli.validate("wow", rule)
:ok
iex(3)> Veli.validate("hello", rule)
:run_error
Link to this function

validate_form(form, rules)

View Source 
@spec validate_form(map(), map()) :: list()

Validate a form with rules.

Returns list of results which contains a tuple that includes key with result.

example

 Example 

iex(1)> form = %{"username" => "john", "age" => 17}
%{"age" => 17, "username" => "john"}
iex(2)> rules = %{"username" => [type: :string, min: 3, max: 32, match: ~r/^[a-zA-Z0-9_]*$/], "age" => [type: :integer, min: 13]}
%{
  "age" => [type: :integer, min: 13],
  "username" => [type: :string, min: 3, max: 32, match: ~r/^[a-zA-Z0-9_]*$/]
}
iex(3)> Veli.validate_form(form, rules)
[{"age", :ok}, {"username", :ok}]
iex(4)> form = %{form | "age" => 10}
%{"age" => 10, "username" => "john"}
iex(5)> Veli.validate_form(form, rules)
[{"age", :min_error}, {"username", :ok}]
Link to this function

validate_list(list, rule)

View Source 
@spec validate_list(
  list(),
  keyword()
) :: list()

Validate list elements with a rule

Returns list of results which contains a tuple that includes index with result.

example

 Example 

iex(1)> rule = [type: :integer, run: fn value -> rem(value, 2) == 0 end]
[type: :integer, max: 100]
iex(2)> Veli.validate_list([4, 6, 8, 10], rule) |> Veli.get_error()
nil
iex(3)> Veli.validate([4, 3, 8], rule) |> Veli.get_error()
{1, :run_error}