Create dump/1 for saving filters.

README.md

@@ -245,7 +245,7 @@ With this example, a query such as this one would filter comments:
 
 # Storing Filters
 
-In addition to parsing parameters, filtrex also enables parsing from a map syntax that is easily encodable to and from JSON. This feature allows storing a filter for future use (e.g. routinely checking for comments that mention "ElixirConf" or todos that are not completed).
+In addition to parsing parameters, filtrex also enables parsing from a map syntax or dumping into it. Maps is easily encodable to and from JSON. This feature allows storing a filter for future use (e.g. routinely checking for comments that mention "ElixirConf" or todos that are not completed).
 
 ```elixir
 # create validation options for keys and formats
@@ -257,7 +257,7 @@ config = defconfig do
 end
 
 # parse a filter from map syntax
-{:ok, filter} = Filtrex.parse(config, %{
+filter_map = %{
   "filter" => %{
     "type" => "all",               # all | any | none
     "conditions" => [
@@ -274,12 +274,15 @@ end
       }
     }]
   }
-})
+}
+{:ok, filter} = Filtrex.parse(config, filter_map)
 
 # Encode filter structure into where clause on Ecto query
 query = from(m in MyApp.Todo, where: m.rating > 90)
   |> Filtrex.query(filter)  # => #Ecto.Query<...
 
+# Dumping filter
+Filtrex.encode(filter) == filter_map
 ```
 
 For more details on the acceptable structure of this map, feel free to take a look at the [example json schema](http://jeremydorn.com/json-editor/?schema=N4IgJgpgZglgdjALjA9nAziAXKAYjAG0QgCdtRlECJsR8jSQAaERATwAcasQUAjAFYQAxomYgOJFFxLIImHCFgMyi9l1r8ho8ZOmk5Cip27GNPdIhLwA5uIhwArgFtsAbRABDAgXGe4bOJwaDQAugC+LMJoYEioGOSsJrSeJCSegSxIEM5GSea8giJiLHoyhonRBC5wiercIJbWcHaRINHOHKmeiCiqZg1NtiBt9XXJFlbDLA4u7iB8KCjU/uLEAB4l4D00LGA7yM67IE7OfIwRLABu3o6m+YNTLSPhryzojnwA+srEJHljHipdKZEAkCAAR0cMHBYGwUG86AgWWIuUSABJwVBaABiAD0kFgCGQaHQePofxer2pLEx0FxBOg8DipPJhEp4SAAA==&value=N4IgZglgNgLgpgJxALlDAngBzikBDKKEAGhAGMB7AOwBMIYJqBnFAbVEqgFcBbK3BjCg5SlHpjwI8MCkmTlqMPBCotSGbALgAPGCRAA3AlxzyAQl3QgAvsQ4VufAfWH6xEqTLkgaFOEwACKgoYAMoqJRV9DVMQeF19I25YgFloAGsbOwVHfnkwKDwAczcKcUlpWVw4AEcuAjU4rFiAIwoHODx+UiSTXDAGnGsAXVImLhaAfUhYRBZkdnBoeDk0Ztwuq1FqOgZmNntc3BoTSZppEQVyzyr5WvqoRpjji8TjWIAmAAYARgA2AC0XwAzACPn8bMNrCNoUAAAA==&theme=bootstrap2&iconlib=fontawesome4&object_layout=grid&show_errors=interaction) or the raw [JSON schema config](resources/schema.json).

lib/filtrex.ex

@@ -42,6 +42,21 @@ defmodule Filtrex do
       do: parse_validated_structure(configs, valid_structured_map)
   end
 
+  @doc """
+  Encode filter into map
+  """
+  @spec encode(Filtrex.t) :: Map.t
+  def encode(%Filtrex{type: type, conditions: conditions, sub_filters: sub_filters}) do
+    %{
+      "filter" =>
+      %{
+        "type" => type,
+        "conditions" => Enum.map(conditions, &Filtrex.Condition.encode_condition/1),
+        "sub_filters" => Enum.map(sub_filters, &encode_sub_filters/1)
+      }
+    }
+  end
+
   @doc """
   Parses a filter expression, like `parse/2`. If any exception is raised when
   parsing the map, a `%Filtrex{empty: true}` struct will be returned.
@@ -190,4 +205,15 @@ defmodule Filtrex do
     values = Map.get(map, key)
     Map.put(map, key, values ++ [value])
   end
+
+
+  defp encode_sub_filters(%Filtrex{type: type, conditions: conditions, sub_filters: sub_filters}) do
+    %{
+      "filter" => %{
+        "type" => type,
+        "conditions" => Enum.map(conditions, &Filtrex.Condition.encode_condition/1),
+        "sub_filters" => Enum.map(sub_filters, &encode_sub_filters/1)
+      }
+    }
+  end
 end

lib/filtrex/ast.ex

@@ -13,7 +13,7 @@ defmodule Filtrex.AST do
 
   defp build_fragments(filter) do
     join = logical_join(filter.type)
-    Enum.map(filter.conditions, &Filtrex.Encoder.encode/1)
+    Enum.map(filter.conditions, &Filtrex.Encoders.Fragment.encode/1)
       |> fragments(join)
       |> build_sub_fragments(join, filter.sub_filters)
   end

lib/filtrex/condition.ex

@@ -15,18 +15,29 @@ defmodule Filtrex.Condition do
     Filtrex.Condition.Number
   ]
 
+  @type any_condition ::
+    Filtrex.Condition.Text.t |
+    Filtrex.Condition.Date.t |
+    Filtrex.Condition.DateTime.t |
+    Filtrex.Condition.Boolean.t |
+    Filtrex.Condition.Number.t
+
+
+
   @callback parse(Filtrex.Type.Config.t, %{inverse: boolean, column: String.t, value: any, comparator: String.t}) :: {:ok, any} | {:error, any}
   @callback type :: Atom.t
   @callback comparators :: [String.t]
-
+  @whitelisted_encode_values ~w(column comparator value type)
+  @required_protocols [Filtrex.Encoders.Fragment, Filtrex.Encoders.Map]
   defstruct column: nil, comparator: nil, value: nil
 
   defmacro __using__(_) do
     quote do
-      import Filtrex.Utils.Encoder
+      import Filtrex.Utils.FragmentEncoderDSL
       alias Filtrex.Condition
       import unquote(__MODULE__), except: [parse: 2]
       @behaviour Filtrex.Condition
+      @after_compile {Filtrex.Condition , :ensure_protocols_implemented}
 
       defstruct type: nil, column: nil, comparator: nil, value: nil, inverse: false
     end
@@ -81,6 +92,23 @@ defmodule Filtrex.Condition do
     if result, do: result, else: {:error, "Unknown filter key '#{key_with_comparator}'"}
   end
 
+  @doc "encode condition into map"
+  @spec encode_condition(any_condition) :: Map.t
+  def encode_condition(condition) do
+    condition
+    |> put_encoded_map_value
+    |> Map.from_struct
+    |> stringify_keys
+    |> Map.update!("type", &Atom.to_string/1)
+    |> Map.take(@whitelisted_encode_values)
+  end
+
+  defp stringify_keys(condition) do
+    Enum.reduce(condition, %{}, fn ({key, value}, acc) ->
+      Map.put(acc, Atom.to_string(key), value)
+    end)
+  end
+
   @doc "Helper method to validate that a comparator is in list"
   @spec validate_comparator(atom, binary, List.t) :: {:ok, binary} | {:error, binary}
   def validate_comparator(type, comparator, comparators) do
@@ -137,9 +165,26 @@ defmodule Filtrex.Condition do
     Application.get_env(:filtrex, :conditions, @modules)
   end
 
+  defp put_encoded_map_value(condition) do
+    %{condition | value: Filtrex.Encoders.Map.encode_map_value(condition)}
+  end
+
   defp condition_module(type) do
     Enum.find(condition_modules(), fn (module) ->
       type == to_string(module.type)
     end)
   end
+
+  def ensure_protocols_implemented(env, _) do
+    Enum.each(@required_protocols, &(check_if_protocol_implemented(&1, env)))
+  end
+
+  defp check_if_protocol_implemented(protocol, %{module: module, file: file}) do
+    try do
+      Protocol.assert_impl!(protocol, module)
+    rescue
+      ArgumentError ->
+        :elixir_errors.warn 1, file, "Please implement #{inspect(protocol)} protocol"
+    end
+  end
 end

lib/filtrex/conditions/boolean.ex

@@ -37,8 +37,12 @@ defmodule Filtrex.Condition.Boolean do
   defp validate_value(bool) when is_boolean(bool), do: bool
   defp validate_value(_), do: nil
 
-  defimpl Filtrex.Encoder do
+  defimpl Filtrex.Encoders.Fragment do
     encoder "equals", "does not equal", "column = ?"
     encoder "does not equal", "equals", "column != ?"
   end
+
+  defimpl Filtrex.Encoders.Map do
+    def encode_map_value(condition), do: to_string(condition.value)
+  end
 end

lib/filtrex/conditions/date.ex

@@ -65,7 +65,7 @@ defmodule Filtrex.Condition.Date do
     end
   end
 
-  defimpl Filtrex.Encoder do
+  defimpl Filtrex.Encoders.Fragment do
     @format Filtrex.Validator.Date.format
 
     encoder "after", "before", "column > ?", &default/1
@@ -93,4 +93,8 @@ defmodule Filtrex.Condition.Date do
 
     defp default_value(timex_date), do: default(timex_date) |> List.first
   end
+
+  defimpl Filtrex.Encoders.Map do
+    def encode_map_value(condition), do: Timex.format!(condition.value, "{YYYY}-{0M}-{0D}")
+  end
 end

lib/filtrex/conditions/datetime.ex

@@ -46,7 +46,7 @@ defmodule Filtrex.Condition.DateTime do
     Timex.parse(value, config.options[:format] || @format)
   end
 
-  defimpl Filtrex.Encoder do
+  defimpl Filtrex.Encoders.Fragment  do
     encoder "after", "before", "column > ?", &default/1
     encoder "before", "after", "column < ?", &default/1
 
@@ -61,4 +61,8 @@ defmodule Filtrex.Condition.DateTime do
       [format]
     end
   end
+
+  defimpl Filtrex.Encoders.Map do
+    def encode_map_value(condition), do: Timex.format!(condition.value, "{ISOdate} {ISOtime}")
+  end
 end

lib/filtrex/conditions/number.ex

@@ -90,12 +90,16 @@ defmodule Filtrex.Condition.Number do
 
   defp parse_value(_, value), do: {:error, parse_value_type_error(value, type())}
 
-  defimpl Filtrex.Encoder do
+  defimpl Filtrex.Encoders.Fragment do
     encoder "equals", "does not equal", "column = ?"
     encoder "does not equal", "equals", "column != ?"
     encoder "greater than", "less than or", "column > ?"
     encoder "less than or", "greater than", "column <= ?"
     encoder "less than", "greater than or", "column < ?"
     encoder "greater than or", "less than", "column >= ?"
   end
+
+  defimpl Filtrex.Encoders.Map do
+    def encode_map_value(condition), do: to_string(condition.value)
+  end
 end

lib/filtrex/conditions/text.ex

@@ -45,11 +45,15 @@ defmodule Filtrex.Condition.Text do
     end
   end
 
-  defimpl Filtrex.Encoder do
+  defimpl Filtrex.Encoders.Fragment do
     encoder "equals", "does not equal", "column = ?"
     encoder "does not equal", "equals", "column != ?"
 
     encoder "contains", "does not contain", "lower(column) LIKE lower(?)", &(["%#{&1}%"])
     encoder "does not contain", "contains", "lower(column) NOT LIKE lower(?)", &(["%#{&1}%"])
   end
+
+  defimpl Filtrex.Encoders.Map do
+    def encode_map_value(condition), do: condition.value
+  end
 end

lib/filtrex/encoder.ex → lib/filtrex/encoders/fragment.ex

@@ -1,8 +1,8 @@
-defprotocol Filtrex.Encoder do
+defprotocol Filtrex.Encoders.Fragment do
   @moduledoc """
   Encodes a condition into `Filtrex.Fragment` as an expression with values.
   Implementing this protocol is required for any new conditions.
-  See `Filtrex.Utils.Encoder` for helper methods with this implementation.
+  See `Filtrex.Utils.FragmentEncoderDSL` for helper methods with this implementation.
 
   Example:
   ```

lib/filtrex/encoders/map.ex

@@ -0,0 +1,5 @@
+defprotocol Filtrex.Encoders.Map do
+  @doc "The function that performs encoding on value"
+  @spec encode_map_value(any) :: String.t
+  def encode_map_value(value)
+end

lib/filtrex/fragment.ex

@@ -1,7 +1,7 @@
 defmodule Filtrex.Fragment do
   @moduledoc """
   `Filtrex.Fragment` is a simple struct used to hold an `expression` and `values`.
-  It is used by `Filtrex.Encoder.encode/1` to turn conditions into ecto queries.
+  It is used by `Filtrex.Encoders.Fragment.encode/1` to turn conditions into ecto queries.
   Example:
   ```
   %Filtrex.Fragment{expression: "(text = ?)", values: ["Buy Milk"]}

lib/filtrex/utils/encoder.ex → lib/filtrex/utils/fragment_encoder_dsl.ex

@@ -1,6 +1,6 @@
-defmodule Filtrex.Utils.Encoder do
+defmodule Filtrex.Utils.FragmentEncoderDSL do
   @moduledoc """
-  Helper methods for implementing the `Filtrex.Encoder` protocol.
+  Helper methods for implementing the `Filtrex.Encoders.FragmentEncoder` protocol.
   """
 
   @doc """
@@ -20,7 +20,7 @@ defmodule Filtrex.Utils.Encoder do
   """
   defmacro encoder(comparator, reverse_comparator, expression, values_function \\ {:&, [], [[{:&, [], [1]}]]}) do
     quote do
-      import Filtrex.Utils.Encoder
+      import Filtrex.Utils.FragmentEncoderDSL
 
       def encode(condition = %{comparator: unquote(comparator), inverse: true}) do
         condition |> struct(inverse: false, comparator: unquote(reverse_comparator)) |> encode

mix.exs

@@ -42,7 +42,8 @@ defmodule Filtrex.Mixfile do
       {:inch_ex, ">= 0.0.0", only: [:dev, :docs]},
       {:plug, "~> 1.1.2", only: :test},
       {:ex_machina, "~> 0.6.1", only: :test},
-      {:mix_test_watch, "~> 0.3", only: :dev, runtime: false}
+      {:mix_test_watch, "~> 0.3", only: :dev, runtime: false},
+      {:dialyxir, "~> 0.5", only: [:dev], runtime: false}
     ]
   end
 

mix.lock

@@ -1,8 +1,10 @@
-%{"certifi": {:hex, :certifi, "0.7.0", "861a57f3808f7eb0c2d1802afeaae0fa5de813b0df0979153cbafcd853ababaf", [:rebar3], [], "hexpm"},
+%{
+  "certifi": {:hex, :certifi, "0.7.0", "861a57f3808f7eb0c2d1802afeaae0fa5de813b0df0979153cbafcd853ababaf", [:rebar3], [], "hexpm"},
   "combine": {:hex, :combine, "0.9.6", "8d1034a127d4cbf6924c8a5010d3534d958085575fa4d9b878f200d79ac78335", [:mix], [], "hexpm"},
   "connection": {:hex, :connection, "1.0.4", "a1cae72211f0eef17705aaededacac3eb30e6625b04a6117c1b2db6ace7d5976", [:mix], [], "hexpm"},
   "db_connection": {:hex, :db_connection, "1.1.2", "2865c2a4bae0714e2213a0ce60a1b12d76a6efba0c51fbda59c9ab8d1accc7a8", [:mix], [{:connection, "~> 1.0.2", [hex: :connection, repo: "hexpm", optional: false]}, {:poolboy, "~> 1.5", [hex: :poolboy, repo: "hexpm", optional: true]}, {:sbroker, "~> 1.0", [hex: :sbroker, repo: "hexpm", optional: true]}], "hexpm"},
   "decimal": {:hex, :decimal, "1.4.1", "ad9e501edf7322f122f7fc151cce7c2a0c9ada96f2b0155b8a09a795c2029770", [:mix], [], "hexpm"},
+  "dialyxir": {:hex, :dialyxir, "0.5.1", "b331b091720fd93e878137add264bac4f644e1ddae07a70bf7062c7862c4b952", [:mix], [], "hexpm"},
   "earmark": {:hex, :earmark, "0.2.1", "ba6d26ceb16106d069b289df66751734802777a3cbb6787026dd800ffeb850f3", [:mix], [], "hexpm"},
   "ecto": {:hex, :ecto, "2.1.2", "8d7bde4170b33e1049850a5dbe0112bfd232824e63c73ee63383df4c6ffd4064", [:mix], [{:db_connection, "~> 1.1", [hex: :db_connection, repo: "hexpm", optional: true]}, {:decimal, "~> 1.2", [hex: :decimal, repo: "hexpm", optional: false]}, {:mariaex, "~> 0.8.0", [hex: :mariaex, repo: "hexpm", optional: true]}, {:poison, "~> 2.2 or ~> 3.0", [hex: :poison, repo: "hexpm", optional: true]}, {:poolboy, "~> 1.5", [hex: :poolboy, repo: "hexpm", optional: false]}, {:postgrex, "~> 0.13.0", [hex: :postgrex, repo: "hexpm", optional: true]}, {:sbroker, "~> 1.0", [hex: :sbroker, repo: "hexpm", optional: true]}], "hexpm"},
   "ex_doc": {:hex, :ex_doc, "0.12.0", "b774aabfede4af31c0301aece12371cbd25995a21bb3d71d66f5c2fe074c603f", [:mix], [{:earmark, "~> 0.2", [hex: :earmark, repo: "hexpm", optional: false]}], "hexpm"},
@@ -21,4 +23,5 @@
   "postgrex": {:hex, :postgrex, "0.13.3", "c277cfb2a9c5034d445a722494c13359e361d344ef6f25d604c2353185682bfc", [:mix], [{:connection, "~> 1.0", [hex: :connection, repo: "hexpm", optional: false]}, {:db_connection, "~> 1.1", [hex: :db_connection, repo: "hexpm", optional: false]}, {:decimal, "~> 1.0", [hex: :decimal, repo: "hexpm", optional: false]}], "hexpm"},
   "ssl_verify_fun": {:hex, :ssl_verify_fun, "1.1.1", "28a4d65b7f59893bc2c7de786dec1e1555bd742d336043fe644ae956c3497fbe", [:make, :rebar], [], "hexpm"},
   "timex": {:hex, :timex, "3.1.7", "71f9c32e13ff4860e86a314303757cc02b3ead5db6e977579a2935225ce9a666", [:mix], [{:combine, "~> 0.7", [hex: :combine, repo: "hexpm", optional: false]}, {:gettext, "~> 0.10", [hex: :gettext, repo: "hexpm", optional: false]}, {:tzdata, "~> 0.1.8 or ~> 0.5", [hex: :tzdata, repo: "hexpm", optional: false]}], "hexpm"},
-  "tzdata": {:hex, :tzdata, "0.5.10", "087e8dfe8c0283473115ad8ca6974b898ecb55ca5c725427a142a79593391e90", [:mix], [{:hackney, "~> 1.0", [hex: :hackney, repo: "hexpm", optional: false]}], "hexpm"}}
+  "tzdata": {:hex, :tzdata, "0.5.10", "087e8dfe8c0283473115ad8ca6974b898ecb55ca5c725427a142a79593391e90", [:mix], [{:hackney, "~> 1.0", [hex: :hackney, repo: "hexpm", optional: false]}], "hexpm"},
+}

test/conditions/boolean_test.exs

@@ -20,24 +20,30 @@ defmodule FiltrexConditionBooleanTest do
       {:ok, condition(false)}
   end
 
+
   test "throwing error for non-boolean value" do
     assert Boolean.parse(@config, params("blah")) ==
       {:error, "Invalid boolean value for blah"}
   end
 
+  test "encoding map value" do
+    assert Filtrex.Encoders.Map.encode_map_value(condition(false)) == "false"
+    assert Filtrex.Encoders.Map.encode_map_value(condition(true)) == "true"
+  end
+
   test "encoding true value" do
-    assert Filtrex.Encoder.encode(condition(true, "equals")) ==
+    assert Filtrex.Encoders.Fragment.encode(condition(true, "equals")) ==
       %Filtrex.Fragment{expression: "? = ?", values: [column_ref(:flag), true]}
 
-    assert Filtrex.Encoder.encode(condition(true, "does not equal")) ==
+    assert Filtrex.Encoders.Fragment.encode(condition(true, "does not equal")) ==
       %Filtrex.Fragment{expression: "? != ?", values: [column_ref(:flag), true]}
   end
 
   test "encoding false value" do
-    assert Filtrex.Encoder.encode(condition(false, "equals")) ==
+    assert Filtrex.Encoders.Fragment.encode(condition(false, "equals")) ==
       %Filtrex.Fragment{expression: "? = ?", values: [column_ref(:flag), false]}
 
-    assert Filtrex.Encoder.encode(condition(false, "does not equal")) ==
+    assert Filtrex.Encoders.Fragment.encode(condition(false, "does not equal")) ==
       %Filtrex.Fragment{expression: "? != ?", values: [column_ref(:flag), false]}
   end
 

test/conditions/date_test.exs

@@ -60,6 +60,10 @@ defmodule FiltrexConditionDateTest do
     }) |> elem(0) == :ok
   end
 
+  test "encoding map value" do
+    assert Filtrex.Encoders.Map.encode_map_value(condition("equals", ~D[2015-01-01])) == @default
+  end
+
   test "encoding as SQL fragments for ecto" do
     assert encode(Date, @column, @default, "after")        == {"? > ?",  [column_ref(:date_column), @default]}
     assert encode(Date, @column, @default, "on or after")  == {"? >= ?", [column_ref(:date_column), @default]}
@@ -81,7 +85,12 @@ defmodule FiltrexConditionDateTest do
 
   defp encode(module, column, value, comparator) do
     {:ok, condition} = module.parse(@config, %{inverse: false, column: column, value: value, comparator: comparator})
-    encoded = Filtrex.Encoder.encode(condition)
+    encoded = Filtrex.Encoders.Fragment.encode(condition)
     {encoded.expression, encoded.values}
   end
+  defp condition(comparator, value) do
+    %Date{type: :number, column: @column,
+              inverse: false, comparator: comparator, value: value}
+  end
+
 end