replace poison with jason

CHANGELOG.md

@@ -4,6 +4,22 @@
 
 ### Enhancements
 
+- BREAKING CHANGE: Replace `:poison` with `:jason` ([#144](https://github.com/commanded/eventstore/pull/144)).
+To support this change the users will need to @derive the Jason.Encoder protocol to all their Events.
+This can be done by either using `@derive Jason.Encoder` before defining the struct. Or using `Protocol.derive/2` for each event.
+Examples below.
+```
+defmodule Event1 do
+  @derive Jason.Encoder
+  defstruct [:id, :data]
+end
+```
+```
+require Protocol
+for event <- [Event1, Event2, Event3] do
+  Protocol.derive(Jason.Encoder, event)
+end
+```
 - Add `:socket` and `:socket_dir` config options ([#132](https://github.com/commanded/eventstore/pull/132)).
 - Rename `uuid` dependency to `elixir_uuid` ([#135](https://github.com/commanded/eventstore/pull/135)).
 - Subscription concurrency ([#134](https://github.com/commanded/eventstore/pull/134)).

config/distributed.exs

@@ -1,6 +1,10 @@
 use Mix.Config
 
-config :logger, backends: []
+config :logger,
+  backends: [],
+  compile_time_purge_matching: [
+    [application: :eventstore]
+  ]
 
 config :ex_unit,
   capture_log: true,

guides/Event Serialization.md

@@ -4,7 +4,16 @@ The default serialization of event data and metadata uses Erlang's [external ter
 
 You must implement the `EventStore.Serializer` behaviour to provide your preferred serialization format.
 
-## Example JSON serializer
+## Jason Serializer
+EventStore includes a JSON serializer using Jason under the `EventStore.JsonSerializer` module. To include it add `{:jason, "~> 1.1"}` to your dependencies. Then configure EventStore to use it.
+
+```elixir
+config :eventstore, EventStore.Storage,
+  serializer: EventStore.JsonSerializer,
+  # ...
+```
+
+## Example JSON (Poison) serializer
 
 The example serializer below serializes event data and metadata to JSON using the [Poison](https://github.com/devinus/poison) library.
 

lib/event_store/json_serializer.ex

@@ -0,0 +1,31 @@
+if Code.ensure_loaded?(Jason) do
+  defmodule EventStore.JsonSerializer do
+    @moduledoc """
+    A serializer that uses the JSON format.
+    """
+
+    @behaviour EventStore.Serializer
+
+    @doc """
+    Serialize given term to JSON binary data.
+    """
+    def serialize(term) do
+      Jason.encode!(term)
+    end
+
+    @doc """
+    Deserialize given JSON binary data to the expected type.
+    """
+    def deserialize(binary, config) do
+      case Keyword.get(config, :type, nil) do
+        nil ->
+          Jason.decode!(binary)
+
+        type ->
+          type
+          |> String.to_existing_atom()
+          |> struct(Jason.decode!(binary, keys: :atoms!))
+      end
+    end
+  end
+end

lib/register_postgres_types.ex

@@ -1,3 +1,3 @@
 if Code.ensure_loaded?(Postgrex) do
-  Postgrex.Types.define(EventStore.PostgresTypes, [], json: Poison)
+  Postgrex.Types.define(EventStore.PostgresTypes, [], json: Jason)
 end

mix.exs

@@ -56,7 +56,7 @@ defmodule EventStore.Mixfile do
       {:ex_doc, "~> 0.19", only: :dev},
       {:markdown, github: "devinus/markdown", only: :dev},
       {:mix_test_watch, "~> 0.9", only: :dev},
-      {:poison, "~> 2.2 or ~> 3.0", optional: true}
+      {:jason, "~> 1.1", optional: true}
     ]
   end
 

mix.lock

@@ -19,7 +19,6 @@
   "markdown": {:git, "https://github.com/devinus/markdown.git", "d065dbcc4e242a85ca2516fdadd0082712871fd8", []},
   "mix_test_watch": {:hex, :mix_test_watch, "0.9.0", "c72132a6071261893518fa08e121e911c9358713f62794a90c95db59042af375", [:mix], [{:file_system, "~> 0.2.1 or ~> 0.3", [hex: :file_system, repo: "hexpm", optional: false]}], "hexpm"},
   "nimble_parsec": {:hex, :nimble_parsec, "0.5.0", "90e2eca3d0266e5c53f8fbe0079694740b9c91b6747f2b7e3c5d21966bba8300", [:mix], [], "hexpm"},
-  "poison": {:hex, :poison, "3.1.0", "d9eb636610e096f86f25d9a46f35a9facac35609a7591b3be3326e99a0484665", [:mix], [], "hexpm"},
   "poolboy": {:hex, :poolboy, "1.5.1", "6b46163901cfd0a1b43d692657ed9d7e599853b3b21b95ae5ae0a777cf9b6ca8", [:rebar], [], "hexpm"},
   "postgrex": {:hex, :postgrex, "0.14.1", "63247d4a5ad6b9de57a0bac5d807e1c32d41e39c04b8a4156a26c63bcd8a2e49", [:mix], [{:connection, "~> 1.0", [hex: :connection, repo: "hexpm", optional: false]}, {:db_connection, "~> 2.0", [hex: :db_connection, repo: "hexpm", optional: false]}, {:decimal, "~> 1.5", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}], "hexpm"},
 }

test/event_store_test.exs

@@ -330,7 +330,10 @@ defmodule EventStoreTest do
     end
   end
 
-  defmodule(ExampleData, do: defstruct([:data]))
+  defmodule ExampleData do
+    @derive Jason.Encoder
+    defstruct([:data])
+  end
 
   test "record snapshot" do
     assert record_snapshot() != nil

test/support/event_factory.ex

@@ -4,6 +4,7 @@ defmodule EventStore.EventFactory do
   @serializer Application.get_env(:eventstore, EventStore.Storage)[:serializer] || EventStore.JsonSerializer
 
   defmodule Event do
+    @derive Jason.Encoder
     defstruct event: nil
   end