Handle UUID's as path values

.travis.yml

@@ -14,3 +14,5 @@ cache:
   directories:
     - _build
     - deps
+notifications:
+  email: false

README.md

@@ -43,7 +43,7 @@ defmodule MyApp.AddMaterializedPathToComments do
 
   def change do
     alter table(:comments) do
-      add :materialized_path, {:array, :integer}, null: false, default: []
+      add :path, {:array, :integer}, null: false
     end
   end
 end
@@ -253,7 +253,7 @@ You can get depth level of the node in the tree
 
 #### `where_depth/2`
 
-You can specify a query to search for nodes with some level of depth
+You can specify a query to search for nodes with some level of depth. It uses `CARDINALITY()` postgres function internally, so ensure your postgres version is at least `9.4`.
 
 ``` elixir
 Comment.where_depth(Comment, is_bigger_than: 2) # => Find all nodes with more than 2 levels deep
@@ -323,3 +323,15 @@ Comment.brutalist_root(comment)
 Comment.brutalist_root?(comment)
 # et.c.
 ```
+
+## About [Brutalist](https://brutalist.press)
+
+<a href="https://brutalist.press">
+  <img src="https://github.com/asiniy/ecto_materialized_path/blob/master/brutalist_logo.png"
+  width="400"
+  height="106"
+  alt="Brutalist">
+</a>
+<br /><br />
+
+`ecto_materialized_path` package is maintained and funded by folks from [Brutalist](https://brutalist.press) - media platform for writing and sharing news and stories with strong focus on traditional values, think-tank level analytics and political research.

lib/ecto_materialized_path.ex

@@ -130,19 +130,19 @@ defmodule EctoMaterializedPath do
   end
 
   defp do_where_depth(query, [is_bigger_than: ibt], column_name) when is_integer(ibt) and ibt > 0 do
-    Ecto.Query.from(q in query, where: fragment("array_length(?, 1)", ^column_name) > ^ibt)
+    Ecto.Query.from(q in query, where: fragment("CARDINALITY(?) > ?", field(q, ^column_name), ^ibt))
   end
   defp do_where_depth(query, [is_bigger_than_or_equal_to: ibtoet], column_name) when is_integer(ibtoet) and ibtoet >= 0 do
-    Ecto.Query.from(q in query, where: fragment("array_length(?, 1)", ^column_name) >= ^ibtoet)
+    Ecto.Query.from(q in query, where: fragment("CARDINALITY(?) >= ?", field(q, ^column_name), ^ibtoet))
   end
   defp do_where_depth(query, [is_equal_to: iet], column_name) when is_integer(iet) and iet > 0 do
-    Ecto.Query.from(q in query, where: fragment("array_length(?, 1)", ^column_name) == ^iet)
+    Ecto.Query.from(q in query, where: fragment("CARDINALITY(?) = ?", field(q, ^column_name), ^iet))
   end
   defp do_where_depth(query, [is_smaller_than_or_equal_to: istoet], column_name) when is_integer(istoet) and istoet >= 0 do
-    Ecto.Query.from(q in query, where: fragment("array_length(?, 1)", ^column_name) <= ^istoet)
+    Ecto.Query.from(q in query, where: fragment("CARDINALITY(?) <= ?", field(q, ^column_name), ^istoet))
   end
   defp do_where_depth(query, [is_smaller_than: ist], column_name) when is_integer(ist) and ist > 0 do
-    Ecto.Query.from(q in query, where: fragment("array_length(?, 1)", ^column_name) < ^ist)
+    Ecto.Query.from(q in query, where: fragment("CARDINALITY(?) < ?", field(q, ^column_name), ^ist))
   end
   defp do_where_depth(_, _, _) do
     raise ArgumentError, "invalid arguments"
@@ -160,6 +160,7 @@ defmodule EctoMaterializedPath do
     changeset |> Ecto.Changeset.change(%{ :"#{column_name}" => new_path })
   end
 
+  def arrange([], _), do: []
   def arrange(nodes_list, column_name) do
     nodes_depth_map = nodes_list |> nodes_by_depth_map(%{}, column_name)
 

lib/ecto_materialized_path/path.ex

@@ -7,7 +7,7 @@ defmodule EctoMaterializedPath.Path do
   """
 
   def cast(list) when is_list(list) do
-    path_is_correct? = Enum.all?(list, fn(path_id) -> is_integer(path_id) end)
+    path_is_correct? = Enum.all?(list, fn(path_id) -> (is_integer(path_id) || is_binary(path_id)) end)
 
     if path_is_correct? do
       { :ok, list }

mix.exs

@@ -2,7 +2,7 @@ defmodule EctoMaterializedPath.Mixfile do
   use Mix.Project
 
   @project_url "https://github.com/asiniy/ecto_materialized_path"
-  @version "0.1.0"
+  @version "0.2.0"
 
   def project do
     [

test/ecto_materialized_path/path_test.exs

@@ -11,11 +11,15 @@ defmodule EctoMaterializedPath.PathTest do
     assert Path.cast([13, 45, 18]) == { :ok, [13, 45, 18] }
   end
 
+  test "passes with UUID's" do
+    assert Path.cast(["38432046-4351-4676-8988-10f0262da113", "a65ce828-52f2-4931-8719-9f7d97723f3b"]) == { :ok, ["38432046-4351-4676-8988-10f0262da113", "a65ce828-52f2-4931-8719-9f7d97723f3b"] }
+  end
+
   test "fails with random value" do
     assert Path.cast(4) == :error
   end
 
   test "fails with wrongs path" do
-    assert Path.cast([14, "ee", 45]) == :error
+    assert Path.cast([14, [:ok], 45]) == :error
   end
 end

test/ecto_materialized_path_test.exs

@@ -367,7 +367,11 @@ defmodule EctoMaterializedPathTest do
       ]
     end
 
-    test "raises an exception when node isn't arranged" do
+    test "returns empty list if there are no children" do
+      assert Comment.arrange([]) == []
+    end
+
+    test "raises an exception when node can't arranged" do
       comment_1 = %Comment{ id: 1 }
         comment_3 = %Comment{ id: 3, path: [1] }
       # parent is missing