Add more validation methods to Mayo.Any, Mayo.Number and Mayo.String

README.md

@@ -27,15 +27,6 @@ defmodule MyModule do
   require Mayo
 
   def call do
-    Mayo.validate %{
-      username: "John",
-      password: "123456"
-    }, %{
-      username: Mayo.Any.string |> Mayo.String.min(4),
-      password: Mayo.Any.string |> Mayo.String.min(6)
-    }
-    # %{username: "John", password: "123456"}
-
     Mayo.validate %{
       username: "John",
       password: "1234"

lib/mayo/any.ex

@@ -101,4 +101,32 @@ defmodule Mayo.Any do
       type: "any.map"
     }}
   end
+
+  @doc """
+  Forbids any value except `nil`.
+
+      iex> Mayo.Any.forbidden(nil)
+      nil
+
+      iex> Mayo.Any.forbidden("test")
+      {:error, %Mayo.Error{type: "any.forbidden"}}
+  """
+  def forbidden(value) when is_nil(value), do: value
+
+  def forbidden(_) do
+    {:error, %Mayo.Error{
+      type: "any.forbidden"
+    }}
+  end
+
+  @doc """
+  Sets the value to `nil`. Used to sanitize output.
+
+      iex> Mayo.Any.strip("test")
+      nil
+
+      iex> Mayo.Any.strip(nil)
+      nil
+  """
+  def strip(_), do: nil
 end

lib/mayo/number.ex

@@ -84,7 +84,7 @@ defmodule Mayo.Number do
       iex> Mayo.Number.odd(2)
       {:error, %Mayo.Error{type: "number.odd"}}
   """
-  def odd(value) when is_number(value) and rem(value, 2) != 0, do: value
+  def odd(value) when is_number(value) and rem(value, 2) == 1, do: value
 
   def odd(value) when is_number(value) do
     {:error, %Mayo.Error{
@@ -112,4 +112,80 @@ defmodule Mayo.Number do
   end
 
   def even(value), do: value
+
+  @doc """
+  Check if the number is an integer.
+
+      iex> Mayo.Number.integer(2)
+      2
+
+      iex> Mayo.Number.integer(3.14)
+      {:error, %Mayo.Error{type: "number.integer"}}
+  """
+  def integer(value) when is_number(value) and is_float(value) do
+    {:error, %Mayo.Error{
+      type: "number.integer"
+    }}
+  end
+
+  def integer(value) when is_number(value), do: value
+
+  def integer(value), do: value
+
+  @doc """
+  Check if the number is a float.
+
+      iex> Mayo.Number.float(3.14)
+      3.14
+
+      iex> Mayo.Number.float(3)
+      {:error, %Mayo.Error{type: "number.float"}}
+  """
+  def float(value) when is_number(value) and is_float(value), do: value
+
+  def float(value) when is_number(value) do
+    {:error, %Mayo.Error{
+      type: "number.float"
+    }}
+  end
+
+  def float(value), do: value
+
+  @doc """
+  Checks if the number is greater than the limit.
+
+      iex> Mayo.Number.greater(4, 3)
+      4
+
+      iex> Mayo.Number.greater(3, 3)
+      {:error, %Mayo.Error{type: "number.greater"}}
+  """
+  def greater(value, limit) when is_number(value) and value > limit, do: value
+
+  def greater(value, _) when is_number(value) do
+    {:error, %Mayo.Error{
+      type: "number.greater"
+    }}
+  end
+
+  def greater(value, _), do: value
+
+  @doc """
+  Checks if the number is less than the limit.
+
+      iex> Mayo.Number.less(2, 3)
+      2
+
+      iex> Mayo.Number.less(3, 3)
+      {:error, %Mayo.Error{type: "number.less"}}
+  """
+  def less(value, limit) when is_number(value) and value < limit, do: value
+
+  def less(value, _) when is_number(value) do
+    {:error, %Mayo.Error{
+      type: "number.less"
+    }}
+  end
+
+  def less(value, _), do: value
 end

lib/mayo/string.ex

@@ -2,9 +2,15 @@ defmodule Mayo.String do
   # http://stackoverflow.com/a/13653180
   @uuid_pattern ~r/^[0-9a-f]{8}-[0-9a-f]{4}-[1-5][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/
 
-  # https://github.com/hapijs/joi/blob/master/lib/string.js#L312
+  # https://github.com/hapijs/joi/blob/v8.4.2/lib/string.js#L375
   @hex_pattern ~r/^[a-f0-9]+$/i
 
+  # https://github.com/hapijs/joi/blob/v8.4.2/lib/string.js#L170
+  @alphanum_pattern ~r/^[a-zA-Z0-9]+$/
+
+  # https://github.com/hapijs/joi/blob/v8.4.2/lib/string.js#L170
+  @token_pattern ~r/^\w+$/
+
   @doc """
   Checks the minimum length of a string.
 
@@ -174,4 +180,46 @@ defmodule Mayo.String do
   end
 
   def credit_card(value), do: value
+
+  @doc """
+  Checks if the string only contains a-z, A-Z, and 0-9.
+
+      iex> Mayo.String.alphanum("Aa0")
+      "Aa0"
+
+      iex> Mayo.String.alphanum("!$!")
+      {:error, %Mayo.Error{type: "string.alphanum"}}
+  """
+  def alphanum(value) when is_binary(value) do
+    if String.match?(value, @alphanum_pattern) do
+      value
+    else
+      {:error, %Mayo.Error{
+        type: "string.alphanum"
+      }}
+    end
+  end
+
+  def alphanum(value), do: value
+
+  @doc """
+  Checks if the string only contains a-z, A-Z, 0-9 and underscore _.
+
+      iex> Mayo.String.token("t_z")
+      "t_z"
+
+      iex> Mayo.String.token("t!z")
+      {:error, %Mayo.Error{type: "string.token"}}
+  """
+  def token(value) when is_binary(value) do
+    if String.match?(value, @token_pattern) do
+      value
+    else
+      {:error, %Mayo.Error{
+        type: "string.token"
+      }}
+    end
+  end
+
+  def token(value), do: value
 end