Merge pull request #17 from valyukov/nested_relationships

Nested relationships

.github/workflows/ci.yml

@@ -1,36 +1,36 @@
 name: CI
 on: [pull_request, push]
 jobs:
- mix_test:
-   name: mix test (Elixir ${{ matrix.elixir }} OTP ${{ matrix.otp }})
-   strategy:
-     matrix:
-       elixir: ['1.7.4', '1.10.1']
-       include:
-         - elixir: '1.7.4'
-           otp: '19.x'
-         - elixir: '1.10.1'
-           otp: '22.x'
-   runs-on: ubuntu-16.04
-   steps:
-     - name: Setup PostgreSQL
-       uses: Harmon758/postgresql-action@v1.0.0
-       with:
-         postgresql db: ex_sieve_test
-         postgresql user: ex_sieve_user
-         postgresql password: ex_sieve_password
-     - uses: actions/checkout@v1
-     - uses: actions/setup-elixir@v1
-       with:
-         otp-version: ${{ matrix.otp }}
-         elixir-version: ${{ matrix.elixir }}
-     - name: Install Dependencies
-       run: mix deps.get
-       env:
-         MIX_ENV: test
-     - name: Run Tests
-       run: mix ecto.migrate && mix test
-       env:
-         MIX_ENV: test
-         DB_USER: ex_sieve_user
-         DB_PASSWORD: ex_sieve_password
+  mix_test:
+    name: mix test (Elixir ${{ matrix.elixir }} OTP ${{ matrix.otp }})
+    strategy:
+      matrix:
+        elixir: ["1.7.4", "1.10.1"]
+        include:
+          - elixir: "1.7.4"
+            otp: "19.x"
+          - elixir: "1.10.1"
+            otp: "22.x"
+    runs-on: ubuntu-latest
+    env:
+      MIX_ENV: test
+      GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+    steps:
+      - name: Setup PostgreSQL
+        uses: Harmon758/postgresql-action@v1.0.0
+        with:
+          postgresql db: ex_sieve_test
+          postgresql user: ex_sieve_user
+          postgresql password: ex_sieve_password
+      - uses: actions/checkout@v1
+      - uses: actions/setup-elixir@v1
+        with:
+          otp-version: ${{ matrix.otp }}
+          elixir-version: ${{ matrix.elixir }}
+      - name: Install Dependencies
+        run: mix deps.get
+      - name: Run Tests
+        run: mix ecto.migrate && mix coveralls.github
+        env:
+          DB_USER: ex_sieve_user
+          DB_PASSWORD: ex_sieve_password

coveralls.json

@@ -0,0 +1,8 @@
+{
+    "skip_files": [
+        "test"
+    ],
+    "coverage_options": {
+        "treat_no_relevant_lines_as_covered": true
+    }
+}

lib/ex_sieve/builder.ex

@@ -6,36 +6,9 @@ defmodule ExSieve.Builder do
 
   @spec call(Ecto.Queryable.t(), Grouping.t(), list(Sort.t())) :: Ecto.Query.t()
   def call(query, grouping, sorts) do
-    relations = build_relations(grouping, sorts)
-
     query
-    |> Join.build(relations)
+    |> Join.build(grouping, sorts)
     |> Where.build(grouping)
     |> OrderBy.build(sorts)
   end
-
-  defp build_relations(grouping, sorts) do
-    sorts_parents = Enum.map(sorts, & &1.attribute.parent)
-
-    grouping
-    |> List.wrap()
-    |> get_grouping_conditions()
-    |> Enum.flat_map(& &1.attributes)
-    |> Enum.map(& &1.parent)
-    |> Enum.concat(sorts_parents)
-    |> Enum.uniq()
-    |> List.delete(:query)
-  end
-
-  defp get_grouping_conditions(groupings, acc \\ [])
-
-  defp get_grouping_conditions([%Grouping{conditions: conditions, groupings: []} | t], acc) do
-    get_grouping_conditions(t, acc ++ conditions)
-  end
-
-  defp get_grouping_conditions([%Grouping{conditions: conditions, groupings: groupings} | t], acc) do
-    get_grouping_conditions(t ++ groupings, acc ++ conditions)
-  end
-
-  defp get_grouping_conditions([], acc), do: acc
 end

lib/ex_sieve/builder/join.ex

@@ -1,22 +1,82 @@
 defmodule ExSieve.Builder.Join do
   @moduledoc false
   alias Ecto.Query.Builder.Join
+  alias ExSieve.Node.{Grouping, Sort}
 
-  @spec build(Ecto.Queryable.t(), Macro.t()) :: Ecto.Query.t()
-  def build(query, relations) do
+  @spec build(Ecto.Queryable.t(), Grouping.t(), list(Sort.t())) :: Ecto.Query.t()
+  def build(query, grouping, sorts) do
+    relations = build_relations(grouping, sorts)
     Enum.reduce(relations, query, &apply_join/2)
   end
 
-  @spec apply_join(Macro.t(), Ecto.Queryable.t()) :: Ecto.Query.t() | no_return
-  defp apply_join(relation, query) do
+  defp build_relations(grouping, sorts) do
+    sorts_parents = Enum.map(sorts, & &1.attribute.parent)
+
+    grouping
+    |> get_grouping_conditions()
+    |> Enum.flat_map(& &1.attributes)
+    |> Enum.map(& &1.parent)
+    |> Enum.concat(sorts_parents)
+    |> all_possible_relations()
+    |> Enum.concat()
+    |> Enum.uniq()
+    |> Enum.sort(&(length(&1) <= length(&2)))
+    |> to_parent_relation_tuple()
+  end
+
+  defp get_grouping_conditions(groupings, acc \\ [])
+
+  defp get_grouping_conditions(%Grouping{} = grouping, acc), do: get_grouping_conditions([grouping], acc)
+
+  defp get_grouping_conditions([%Grouping{conditions: conditions, groupings: []} | t], acc) do
+    get_grouping_conditions(t, acc ++ conditions)
+  end
+
+  defp get_grouping_conditions([%Grouping{conditions: conditions, groupings: groupings} | t], acc) do
+    get_grouping_conditions(t ++ groupings, acc ++ conditions)
+  end
+
+  defp get_grouping_conditions([], acc), do: acc
+
+  defp all_possible_relations(parents) do
+    Enum.map(parents, fn parent_list ->
+      {relations, _} =
+        Enum.map_reduce(parent_list, [], fn el, acc ->
+          acc = [el | acc]
+          {acc, acc}
+        end)
+
+      relations
+    end)
+  end
+
+  defp to_parent_relation_tuple(parents) do
+    Enum.map(parents, fn parent_list ->
+      case parent_list do
+        [] -> {nil, :query}
+        [head] -> {nil, head}
+        [head | tail] -> {tail |> Enum.reverse() |> Enum.join("_"), head}
+      end
+    end)
+  end
+
+  defp apply_join({parent, relation} = pr, query) do
     query
     |> Macro.escape()
-    |> Join.build(:inner, [Macro.var(:query, __MODULE__)], expr(relation), nil, nil, relation, nil, nil, __ENV__)
+    |> Join.build(:inner, join_binding(parent), expr(relation), nil, nil, join_as(pr), nil, nil, __ENV__)
     |> elem(0)
     |> Code.eval_quoted()
     |> elem(0)
   end
 
+  defp join_binding(nil), do: [Macro.var(:query, __MODULE__)]
+
+  defp join_binding(parent), do: [{String.to_atom(parent), Macro.var(:query, __MODULE__)}]
+
+  defp join_as({nil, relation}), do: relation
+
+  defp join_as({parent, relation}), do: :"#{parent}_#{relation}"
+
   defp expr(relation) do
     quote do
       unquote(Macro.var(relation, __MODULE__)) in assoc(query, unquote(relation))

lib/ex_sieve/builder/order_by.ex

@@ -12,6 +12,11 @@ defmodule ExSieve.Builder.OrderBy do
     end)
   end
 
-  defp dynamic_sort(:query, name), do: dynamic([p], field(p, ^name))
-  defp dynamic_sort(parent, name), do: dynamic([{^parent, p}], field(p, ^name))
+  defp dynamic_sort([], name), do: dynamic([p], field(p, ^name))
+  defp dynamic_sort([parent], name), do: dynamic([{^parent, p}], field(p, ^name))
+
+  defp dynamic_sort(parents, name) do
+    parent = parents |> Enum.join("_") |> String.to_atom()
+    dynamic([{^parent, p}], field(p, ^name))
+  end
 end