From 05ab12cab8f8bcd4900936e2d75fcaf648f7d17e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Tue, 4 Oct 2016 23:15:41 +0200
Subject: [PATCH 01/18] Make a working GET request with Tesla

---
 lib/dayron/adapters/tesla_adapter.ex          |  66 ++++++++
 mix.exs                                       |   1 +
 mix.lock                                      |   9 +-
 .../dayron/adapters/tesla_adapter_test.exs    | 152 ++++++++++++++++++
 4 files changed, 224 insertions(+), 4 deletions(-)
 create mode 100644 lib/dayron/adapters/tesla_adapter.ex
 create mode 100644 test/lib/dayron/adapters/tesla_adapter_test.exs

diff --git a/lib/dayron/adapters/tesla_adapter.ex b/lib/dayron/adapters/tesla_adapter.ex
new file mode 100644
index 0000000..d9be3c1
--- /dev/null
+++ b/lib/dayron/adapters/tesla_adapter.ex
@@ -0,0 +1,66 @@
+defmodule Dayron.TeslaAdapter do
+  @moduledoc """
+  Makes http requests using Tesla library.
+  Use this adapter to make http requests to an external Rest API.
+
+  ## Example config
+      config :my_app, MyApp.Repo,
+        adapter: Dayron.TeslaAdapter,
+        url: "https://api.example.com"
+  """
+  @behaviour Dayron.Adapter
+
+  defmodule Client do
+    @moduledoc """
+    A Tesla Client implementation, sending json requests, parsing
+    json responses to Maps or a List of Maps. Maps keys are also converted to
+    atoms by default.
+    """
+    use Tesla
+
+    plug Tesla.Middleware.JSON
+
+    adapter Tesla.Adapter.Hackney
+  end
+
+  @doc """
+  Implementation for `Dayron.Adapter.get/3`.
+  """
+  def get(url, headers \\ [], opts \\ []) do
+    Client.get(url, headers: headers) |> translate_response
+  end
+
+  @doc """
+  Implementation for `Dayron.Adapter.post/4`.
+  """
+  def post(url, body, headers \\ [], opts \\ []) do
+    Client.post(url, body, headers: headers) |> translate_response
+  end
+
+  @doc """
+  Implementation for `Dayron.Adapter.patch/4`.
+  """
+  def patch(url, body, headers \\ [], opts \\ []) do
+    Client.patch(url, body, headers: headers) |> translate_response
+  end
+
+  @doc """
+  Implementation for `Dayron.Adapter.delete/3`.
+  """
+  def delete(url, headers \\ [], opts \\ []) do
+    Client.delete(url, headers: headers) |> translate_response
+  end
+
+  defp translate_response(%Tesla.Env{} = response) do
+    {:ok, %Dayron.Response{
+        status_code: response.status,
+        body: response.body |> Poison.decode! |> IO.inspect,
+        headers: response.headers |> Map.to_list
+      }
+    }
+  end
+  defp translate_response({:error, response}) do
+    data = response |> Map.from_struct
+    {:error, struct(Dayron.ClientError, data)}
+  end
+end
diff --git a/mix.exs b/mix.exs
index 55a6290..4b5a609 100644
--- a/mix.exs
+++ b/mix.exs
@@ -45,6 +45,7 @@ defmodule Dayron.Mixfile do
     [
       {:poison,       "~> 1.5 or ~> 2.0"},
       {:httpoison,    "~> 0.8.0"},
+      {:tesla,        "~> 0.5.0", optional: true},
       {:crutches,     "~> 1.0.0"},
       {:credo,        "~> 0.3",     only: [:dev, :test]},
       {:bypass,       "~> 0.1",     only: :test},
diff --git a/mix.lock b/mix.lock
index c589b7e..4ef92c1 100644
--- a/mix.lock
+++ b/mix.lock
@@ -1,5 +1,5 @@
 %{"bunt": {:hex, :bunt, "0.1.5", "c378ea1698232597d3778e4b83234dcea4a60e7c28114b0fe53657a2c0d8885e", [:mix], []},
-  "bypass": {:hex, :bypass, "0.5.1", "cf3e8a4d376ee1dcd89bf362dfaf1f4bf4a6e19895f52fdc2bafbd8207ce435f", [:mix], [{:plug, "~> 1.0", [hex: :plug, optional: false]}, {:cowboy, "~> 1.0", [hex: :cowboy, optional: false]}]},
+  "bypass": {:hex, :bypass, "0.5.1", "cf3e8a4d376ee1dcd89bf362dfaf1f4bf4a6e19895f52fdc2bafbd8207ce435f", [:mix], [{:cowboy, "~> 1.0", [hex: :cowboy, optional: false]}, {:plug, "~> 1.0", [hex: :plug, optional: false]}]},
   "certifi": {:hex, :certifi, "0.4.0", "a7966efb868b179023618d29a407548f70c52466bf1849b9e8ebd0e34b7ea11f", [:rebar3], []},
   "cowboy": {:hex, :cowboy, "1.0.4", "a324a8df9f2316c833a470d918aaf73ae894278b8aa6226ce7a9bf699388f878", [:rebar, :make], [{:cowlib, "~> 1.0.0", [hex: :cowlib, optional: false]}, {:ranch, "~> 1.0", [hex: :ranch, optional: false]}]},
   "cowlib": {:hex, :cowlib, "1.0.2", "9d769a1d062c9c3ac753096f868ca121e2730b9a377de23dec0f7e08b1df84ee", [:make], []},
@@ -7,9 +7,9 @@
   "crutches": {:hex, :crutches, "1.0.0", "34675f0c88f25a3a6d2a77912194beaece9bf835f9f2f5627027b4a19125aaa6", [:mix], []},
   "earmark": {:hex, :earmark, "0.2.1", "ba6d26ceb16106d069b289df66751734802777a3cbb6787026dd800ffeb850f3", [:mix], []},
   "ex_doc": {:hex, :ex_doc, "0.11.5", "0dc51cb84f8312162a2313d6c71573a9afa332333d8a332bb12540861b9834db", [:mix], [{:earmark, "~> 0.1.17 or ~> 0.2", [hex: :earmark, optional: true]}]},
-  "excoveralls": {:hex, :excoveralls, "0.5.4", "1a6e116bcf980da8b7fe33140c1d7e61aa0a4e51951cadbfacc420c12d2b9b8f", [:mix], [{:hackney, ">= 0.12.0", [hex: :hackney, optional: false]}, {:exjsx, "~> 3.0", [hex: :exjsx, optional: false]}]},
+  "excoveralls": {:hex, :excoveralls, "0.5.4", "1a6e116bcf980da8b7fe33140c1d7e61aa0a4e51951cadbfacc420c12d2b9b8f", [:mix], [{:exjsx, "~> 3.0", [hex: :exjsx, optional: false]}, {:hackney, ">= 0.12.0", [hex: :hackney, optional: false]}]},
   "exjsx": {:hex, :exjsx, "3.2.0", "7136cc739ace295fc74c378f33699e5145bead4fdc1b4799822d0287489136fb", [:mix], [{:jsx, "~> 2.6.2", [hex: :jsx, optional: false]}]},
-  "hackney": {:hex, :hackney, "1.6.0", "8d1e9440c9edf23bf5e5e2fe0c71de03eb265103b72901337394c840eec679ac", [:rebar3], [{:ssl_verify_fun, "1.1.0", [hex: :ssl_verify_fun, optional: false]}, {:mimerl, "1.0.2", [hex: :mimerl, optional: false]}, {:metrics, "1.0.1", [hex: :metrics, optional: false]}, {:idna, "1.2.0", [hex: :idna, optional: false]}, {:certifi, "0.4.0", [hex: :certifi, optional: false]}]},
+  "hackney": {:hex, :hackney, "1.6.0", "8d1e9440c9edf23bf5e5e2fe0c71de03eb265103b72901337394c840eec679ac", [:rebar3], [{:certifi, "0.4.0", [hex: :certifi, optional: false]}, {:idna, "1.2.0", [hex: :idna, optional: false]}, {:metrics, "1.0.1", [hex: :metrics, optional: false]}, {:mimerl, "1.0.2", [hex: :mimerl, optional: false]}, {:ssl_verify_fun, "1.1.0", [hex: :ssl_verify_fun, optional: false]}]},
   "httpoison": {:hex, :httpoison, "0.8.3", "b675a3fdc839a0b8d7a285c6b3747d6d596ae70b6ccb762233a990d7289ccae4", [:mix], [{:hackney, "~> 1.6.0", [hex: :hackney, optional: false]}]},
   "idna": {:hex, :idna, "1.2.0", "ac62ee99da068f43c50dc69acf700e03a62a348360126260e87f2b54eced86b2", [:rebar3], []},
   "inch_ex": {:hex, :inch_ex, "0.5.1", "c1c18966c935944cbb2d273796b36e44fab3c54fd59f906ff026a686205b4e14", [:mix], [{:poison, "~> 1.5 or ~> 2.0", [hex: :poison, optional: false]}]},
@@ -19,4 +19,5 @@
   "plug": {:hex, :plug, "1.1.4", "2eee0e85ad420db96e075b3191d3764d6fff61422b101dc5b02e9cce99cacfc7", [:mix], [{:cowboy, "~> 1.0", [hex: :cowboy, optional: true]}]},
   "poison": {:hex, :poison, "1.5.2", "560bdfb7449e3ddd23a096929fb9fc2122f709bcc758b2d5d5a5c7d0ea848910", [:mix], []},
   "ranch": {:hex, :ranch, "1.2.1", "a6fb992c10f2187b46ffd17ce398ddf8a54f691b81768f9ef5f461ea7e28c762", [:make], []},
-  "ssl_verify_fun": {:hex, :ssl_verify_fun, "1.1.0", "edee20847c42e379bf91261db474ffbe373f8acb56e9079acb6038d4e0bf414f", [:rebar, :make], []}}
+  "ssl_verify_fun": {:hex, :ssl_verify_fun, "1.1.0", "edee20847c42e379bf91261db474ffbe373f8acb56e9079acb6038d4e0bf414f", [:rebar, :make], []},
+  "tesla": {:hex, :tesla, "0.5.2", "614297046c638b8c1695e8b6e63e6bffd107c07a67e4cb8cc4bb46598be735f1", [:mix], [{:exjsx, ">= 0.1.0", [hex: :exjsx, optional: true]}, {:hackney, "~> 1.6.0", [hex: :hackney, optional: true]}, {:ibrowse, "~> 4.2", [hex: :ibrowse, optional: true]}, {:poison, ">= 1.0.0", [hex: :poison, optional: true]}]}}
diff --git a/test/lib/dayron/adapters/tesla_adapter_test.exs b/test/lib/dayron/adapters/tesla_adapter_test.exs
new file mode 100644
index 0000000..8bfea9d
--- /dev/null
+++ b/test/lib/dayron/adapters/tesla_adapter_test.exs
@@ -0,0 +1,152 @@
+defmodule Dayron.TeslaAdapterTest do
+  use ExUnit.Case, async: true
+  alias Dayron.TeslaAdapter
+
+  setup do
+    bypass = Bypass.open
+    {:ok, bypass: bypass, api_url: "http://localhost:#{bypass.port}"}
+  end
+
+  test "returns a decoded body for a valid get request", %{bypass: bypass, api_url: api_url} do
+    Bypass.expect bypass, fn conn ->
+      assert "/resources/id" == conn.request_path
+      assert "GET" == conn.method
+      Plug.Conn.resp(conn, 200, ~s<{"name": "Full Name", "address":{"street": "Elm Street", "zipcode": "88888"}}>)
+    end
+    response = TeslaAdapter.get("#{api_url}/resources/id")
+    assert {:ok, %Dayron.Response{status_code: 200, body: body}} = response
+    assert body["name"] == "Full Name"
+    assert body["address"] == %{"street" => "Elm Street", "zipcode" => "88888"}
+  end
+
+  @tag skip: "TBD"
+  test "handles response body 'ok'", %{bypass: bypass, api_url: api_url} do
+    Bypass.expect bypass, fn conn ->
+      assert "/resources/id" == conn.request_path
+      assert "GET" == conn.method
+      Plug.Conn.resp(conn, 200, "ok")
+    end
+    response = TeslaAdapter.get("#{api_url}/resources/id")
+    assert {:ok, %Dayron.Response{status_code: 200, body: body}} = response
+    assert body == %{}
+  end
+
+  @tag skip: "TBD"
+  test "handles invalid json body", %{bypass: bypass, api_url: api_url} do
+    Bypass.expect bypass, fn conn ->
+      assert "/resources/id" == conn.request_path
+      assert "GET" == conn.method
+      Plug.Conn.resp(conn, 200, "{invalid_json=1}")
+    end
+    response = TeslaAdapter.get("#{api_url}/resources/id")
+    assert {:ok, %Dayron.Response{status_code: 200, body: body}} = response
+    assert body == "{invalid_json=1}"
+  end
+
+  @tag skip: "TBD"
+  test "returns a decoded body for a response list", %{bypass: bypass, api_url: api_url} do
+    Bypass.expect bypass, fn conn ->
+      assert "/resources" == conn.request_path
+      assert "GET" == conn.method
+      Plug.Conn.resp(conn, 200, ~s<[{"name": "First Resource"}, {"name": "Second Resource"}]>)
+    end
+    response = TeslaAdapter.get("#{api_url}/resources")
+    assert {:ok, %Dayron.Response{status_code: 200, body: body}} = response
+    [first, second | _t] = body
+    assert first[:name] == "First Resource"
+    assert second[:name] == "Second Resource"
+  end
+
+  @tag skip: "TBD"
+  test "accepts query parameters and headers", %{bypass: bypass, api_url: api_url} do
+    Bypass.expect bypass, fn conn ->
+      assert "/resources" == conn.request_path
+      assert "q=qu+ery&page=2" == conn.query_string
+      assert [{"accept", "application/json"} | _] = conn.req_headers
+      assert "GET" == conn.method
+      Plug.Conn.resp(conn, 200, "")
+    end
+    response = TeslaAdapter.get("#{api_url}/resources", [{"accept", "application/json"}], [params: [{:q, "qu ery"}, {:page, 2}]])
+    assert {:ok, %Dayron.Response{status_code: 200, body: _}} = response
+  end
+
+  @tag skip: "TBD"
+  test "accepts custom headers", %{bypass: bypass, api_url: api_url} do
+    Bypass.expect bypass, fn conn ->
+      assert "/resources/id" == conn.request_path
+      assert [_a, _b, {"accesstoken", "token"} | _] = conn.req_headers
+      assert "GET" == conn.method
+      Plug.Conn.resp(conn, 200, "")
+    end
+    response = TeslaAdapter.get("#{api_url}/resources/id", [accesstoken: "token"])
+    assert {:ok, %Dayron.Response{status_code: 200, body: _}} = response
+  end
+
+  @tag skip: "TBD"
+  test "returns a 404 response", %{bypass: bypass, api_url: api_url} do
+    Bypass.expect bypass, fn conn ->
+      assert "/resources/invalid" == conn.request_path
+      assert "GET" == conn.method
+      Plug.Conn.resp(conn, 404, "")
+    end
+    response = TeslaAdapter.get("#{api_url}/resources/invalid")
+    assert {:ok, %Dayron.Response{status_code: 404, body: _}} = response
+  end
+
+  @tag skip: "TBD"
+  test "returns a 500 error response", %{bypass: bypass, api_url: api_url} do
+    Bypass.expect bypass, fn conn ->
+      assert "/resources/server-error" == conn.request_path
+      assert "GET" == conn.method
+      Plug.Conn.resp(conn, 500, "")
+    end
+    response = TeslaAdapter.get("#{api_url}/resources/server-error")
+    assert {:ok, %Dayron.Response{status_code: 500, body: _}} = response
+  end
+
+  @tag skip: "TBD"
+  test "returns an error for invalid server" do
+    response = TeslaAdapter.get("http://localhost:0001/resources/error")
+    assert {:error, %Dayron.ClientError{reason: :econnrefused}} = response
+  end
+
+  @tag skip: "TBD"
+  test "returns a decoded body for a valid post request", %{bypass: bypass, api_url: api_url} do
+    Bypass.expect bypass, fn conn ->
+      assert "/resources" == conn.request_path
+      assert [{"accept", "application/json"} | _] = conn.req_headers
+      assert "POST" == conn.method
+      Plug.Conn.resp(conn, 201, ~s<{"name": "Full Name", "age": 30}>)
+    end
+    response = TeslaAdapter.post("#{api_url}/resources", %{name: "Full Name", age: 30}, [{"accept", "application/json"}])
+    assert {:ok, %Dayron.Response{status_code: 201, body: body}} = response
+    assert body[:name] == "Full Name"
+    assert body[:age] == 30
+  end
+
+  @tag skip: "TBD"
+  test "returns a decoded body for a valid patch request", %{bypass: bypass, api_url: api_url} do
+    Bypass.expect bypass, fn conn ->
+      assert "/resources/id" == conn.request_path
+      assert [{"accept", "application/json"} | _] = conn.req_headers
+      assert "PATCH" == conn.method
+      Plug.Conn.resp(conn, 200, ~s<{"name": "Full Name", "age": 30}>)
+    end
+    response = TeslaAdapter.patch("#{api_url}/resources/id", %{name: "Full Name", age: 30}, [{"accept", "application/json"}])
+    assert {:ok, %Dayron.Response{status_code: 200, body: body}} = response
+    assert body[:name] == "Full Name"
+    assert body[:age] == 30
+  end
+
+  @tag skip: "TBD"
+  test "returns an empty body for a valid delete request", %{bypass: bypass, api_url: api_url} do
+    Bypass.expect bypass, fn conn ->
+      assert "/resources/id" == conn.request_path
+      assert [{"content-type", "application/json"}|_] = conn.req_headers
+      assert "DELETE" == conn.method
+      Plug.Conn.resp(conn, 204, "")
+    end
+    response = TeslaAdapter.delete("#{api_url}/resources/id", [{"content-type", "application/json"}])
+    assert {:ok, %Dayron.Response{status_code: 204, body: nil}} = response
+  end
+end

From bd779998fa5e47b6b1b1871d0137954deb648c24 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Tue, 11 Oct 2016 08:10:11 +0200
Subject: [PATCH 02/18] Use custom JSON decoding due to special requirements

---
 lib/dayron/adapters/tesla_adapter.ex            | 13 ++++++++++---
 test/lib/dayron/adapters/tesla_adapter_test.exs |  4 ++--
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/lib/dayron/adapters/tesla_adapter.ex b/lib/dayron/adapters/tesla_adapter.ex
index d9be3c1..c4d3898 100644
--- a/lib/dayron/adapters/tesla_adapter.ex
+++ b/lib/dayron/adapters/tesla_adapter.ex
@@ -18,8 +18,6 @@ defmodule Dayron.TeslaAdapter do
     """
     use Tesla
 
-    plug Tesla.Middleware.JSON
-
     adapter Tesla.Adapter.Hackney
   end
 
@@ -54,7 +52,7 @@ defmodule Dayron.TeslaAdapter do
   defp translate_response(%Tesla.Env{} = response) do
     {:ok, %Dayron.Response{
         status_code: response.status,
-        body: response.body |> Poison.decode! |> IO.inspect,
+        body: translate_response_body(response.body),
         headers: response.headers |> Map.to_list
       }
     }
@@ -63,4 +61,13 @@ defmodule Dayron.TeslaAdapter do
     data = response |> Map.from_struct
     {:error, struct(Dayron.ClientError, data)}
   end
+
+  defp translate_response_body(body) do
+    try do
+      body |> Poison.decode!(keys: :atoms)
+    rescue
+      Poison.SyntaxError -> body
+    end
+  end
+
 end
diff --git a/test/lib/dayron/adapters/tesla_adapter_test.exs b/test/lib/dayron/adapters/tesla_adapter_test.exs
index 8bfea9d..1bf8a7d 100644
--- a/test/lib/dayron/adapters/tesla_adapter_test.exs
+++ b/test/lib/dayron/adapters/tesla_adapter_test.exs
@@ -15,8 +15,8 @@ defmodule Dayron.TeslaAdapterTest do
     end
     response = TeslaAdapter.get("#{api_url}/resources/id")
     assert {:ok, %Dayron.Response{status_code: 200, body: body}} = response
-    assert body["name"] == "Full Name"
-    assert body["address"] == %{"street" => "Elm Street", "zipcode" => "88888"}
+    assert body[:name] == "Full Name"
+    assert body[:address] == %{street: "Elm Street", zipcode: "88888"}
   end
 
   @tag skip: "TBD"

From 9006d2ca514c0efc8f71a4d3d61d11514ccf52dc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Tue, 11 Oct 2016 08:14:06 +0200
Subject: [PATCH 03/18] Add note about using Tesla for JSON decoding

---
 lib/dayron/adapters/tesla_adapter.ex            | 6 ++++++
 test/lib/dayron/adapters/tesla_adapter_test.exs | 3 ---
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/lib/dayron/adapters/tesla_adapter.ex b/lib/dayron/adapters/tesla_adapter.ex
index c4d3898..7ae298e 100644
--- a/lib/dayron/adapters/tesla_adapter.ex
+++ b/lib/dayron/adapters/tesla_adapter.ex
@@ -18,6 +18,11 @@ defmodule Dayron.TeslaAdapter do
     """
     use Tesla
 
+    # TODO: If the Tesla JSON decoding was a bit more flexible, properly
+    # returning errors along with raw output and perhaps allowing a force
+    # flag to ignore content-type header contents, we could use that instead
+    # of our own custom decoding. Perhaps a pull request would do it..
+
     adapter Tesla.Adapter.Hackney
   end
 
@@ -62,6 +67,7 @@ defmodule Dayron.TeslaAdapter do
     {:error, struct(Dayron.ClientError, data)}
   end
 
+  defp translate_response_body("ok"), do: %{}
   defp translate_response_body(body) do
     try do
       body |> Poison.decode!(keys: :atoms)
diff --git a/test/lib/dayron/adapters/tesla_adapter_test.exs b/test/lib/dayron/adapters/tesla_adapter_test.exs
index 1bf8a7d..ba0f916 100644
--- a/test/lib/dayron/adapters/tesla_adapter_test.exs
+++ b/test/lib/dayron/adapters/tesla_adapter_test.exs
@@ -19,7 +19,6 @@ defmodule Dayron.TeslaAdapterTest do
     assert body[:address] == %{street: "Elm Street", zipcode: "88888"}
   end
 
-  @tag skip: "TBD"
   test "handles response body 'ok'", %{bypass: bypass, api_url: api_url} do
     Bypass.expect bypass, fn conn ->
       assert "/resources/id" == conn.request_path
@@ -31,7 +30,6 @@ defmodule Dayron.TeslaAdapterTest do
     assert body == %{}
   end
 
-  @tag skip: "TBD"
   test "handles invalid json body", %{bypass: bypass, api_url: api_url} do
     Bypass.expect bypass, fn conn ->
       assert "/resources/id" == conn.request_path
@@ -43,7 +41,6 @@ defmodule Dayron.TeslaAdapterTest do
     assert body == "{invalid_json=1}"
   end
 
-  @tag skip: "TBD"
   test "returns a decoded body for a response list", %{bypass: bypass, api_url: api_url} do
     Bypass.expect bypass, fn conn ->
       assert "/resources" == conn.request_path

From c20fbe6b10e6f23b1736c1b8439e6f3e52af20cb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Tue, 11 Oct 2016 08:20:20 +0200
Subject: [PATCH 04/18] Support query parameters for Tesla

---
 lib/dayron/adapters/tesla_adapter.ex            | 3 ++-
 test/lib/dayron/adapters/tesla_adapter_test.exs | 1 -
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/dayron/adapters/tesla_adapter.ex b/lib/dayron/adapters/tesla_adapter.ex
index 7ae298e..5dddc24 100644
--- a/lib/dayron/adapters/tesla_adapter.ex
+++ b/lib/dayron/adapters/tesla_adapter.ex
@@ -30,7 +30,8 @@ defmodule Dayron.TeslaAdapter do
   Implementation for `Dayron.Adapter.get/3`.
   """
   def get(url, headers \\ [], opts \\ []) do
-    Client.get(url, headers: headers) |> translate_response
+    query = Keyword.get(opts, :params, [])
+    Client.get(url, headers: headers, query: query) |> translate_response
   end
 
   @doc """
diff --git a/test/lib/dayron/adapters/tesla_adapter_test.exs b/test/lib/dayron/adapters/tesla_adapter_test.exs
index ba0f916..a9a5466 100644
--- a/test/lib/dayron/adapters/tesla_adapter_test.exs
+++ b/test/lib/dayron/adapters/tesla_adapter_test.exs
@@ -54,7 +54,6 @@ defmodule Dayron.TeslaAdapterTest do
     assert second[:name] == "Second Resource"
   end
 
-  @tag skip: "TBD"
   test "accepts query parameters and headers", %{bypass: bypass, api_url: api_url} do
     Bypass.expect bypass, fn conn ->
       assert "/resources" == conn.request_path

From 967b4cedbe28aa6da23bf6094544bd32de4f2540 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Tue, 11 Oct 2016 08:29:17 +0200
Subject: [PATCH 05/18] Make sure that Tesla supports custom headers

---
 test/lib/dayron/adapters/tesla_adapter_test.exs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/test/lib/dayron/adapters/tesla_adapter_test.exs b/test/lib/dayron/adapters/tesla_adapter_test.exs
index a9a5466..c5d4af0 100644
--- a/test/lib/dayron/adapters/tesla_adapter_test.exs
+++ b/test/lib/dayron/adapters/tesla_adapter_test.exs
@@ -66,11 +66,10 @@ defmodule Dayron.TeslaAdapterTest do
     assert {:ok, %Dayron.Response{status_code: 200, body: _}} = response
   end
 
-  @tag skip: "TBD"
   test "accepts custom headers", %{bypass: bypass, api_url: api_url} do
     Bypass.expect bypass, fn conn ->
       assert "/resources/id" == conn.request_path
-      assert [_a, _b, {"accesstoken", "token"} | _] = conn.req_headers
+      assert {"accesstoken", "token"} in conn.req_headers
       assert "GET" == conn.method
       Plug.Conn.resp(conn, 200, "")
     end

From 2e4d7864524c7d240ff0bc00cae2074b4b5f8e99 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Tue, 11 Oct 2016 08:30:44 +0200
Subject: [PATCH 06/18] Make sure that Tesla returns proper error response
 codes

---
 test/lib/dayron/adapters/tesla_adapter_test.exs | 2 --
 1 file changed, 2 deletions(-)

diff --git a/test/lib/dayron/adapters/tesla_adapter_test.exs b/test/lib/dayron/adapters/tesla_adapter_test.exs
index c5d4af0..5743dc3 100644
--- a/test/lib/dayron/adapters/tesla_adapter_test.exs
+++ b/test/lib/dayron/adapters/tesla_adapter_test.exs
@@ -77,7 +77,6 @@ defmodule Dayron.TeslaAdapterTest do
     assert {:ok, %Dayron.Response{status_code: 200, body: _}} = response
   end
 
-  @tag skip: "TBD"
   test "returns a 404 response", %{bypass: bypass, api_url: api_url} do
     Bypass.expect bypass, fn conn ->
       assert "/resources/invalid" == conn.request_path
@@ -88,7 +87,6 @@ defmodule Dayron.TeslaAdapterTest do
     assert {:ok, %Dayron.Response{status_code: 404, body: _}} = response
   end
 
-  @tag skip: "TBD"
   test "returns a 500 error response", %{bypass: bypass, api_url: api_url} do
     Bypass.expect bypass, fn conn ->
       assert "/resources/server-error" == conn.request_path

From 74143b884f71b89d2830314b6137f881b32c1c88 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Tue, 11 Oct 2016 08:39:11 +0200
Subject: [PATCH 07/18] Translate Tesla errors to properly handle invalid
 server, etc

---
 lib/dayron/adapters/tesla_adapter.ex            | 9 ++++++++-
 test/lib/dayron/adapters/tesla_adapter_test.exs | 1 -
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/lib/dayron/adapters/tesla_adapter.ex b/lib/dayron/adapters/tesla_adapter.ex
index 5dddc24..ca38635 100644
--- a/lib/dayron/adapters/tesla_adapter.ex
+++ b/lib/dayron/adapters/tesla_adapter.ex
@@ -31,7 +31,11 @@ defmodule Dayron.TeslaAdapter do
   """
   def get(url, headers \\ [], opts \\ []) do
     query = Keyword.get(opts, :params, [])
-    Client.get(url, headers: headers, query: query) |> translate_response
+    try do
+      Client.get(url, headers: headers, query: query) |> translate_response
+    rescue
+      e in Tesla.Error -> translate_error(e)
+    end
   end
 
   @doc """
@@ -77,4 +81,7 @@ defmodule Dayron.TeslaAdapter do
     end
   end
 
+  defp translate_error(%Tesla.Error{reason: reason}) do
+    {:error, %Dayron.ClientError{reason: reason}}
+  end
 end
diff --git a/test/lib/dayron/adapters/tesla_adapter_test.exs b/test/lib/dayron/adapters/tesla_adapter_test.exs
index 5743dc3..14c464d 100644
--- a/test/lib/dayron/adapters/tesla_adapter_test.exs
+++ b/test/lib/dayron/adapters/tesla_adapter_test.exs
@@ -97,7 +97,6 @@ defmodule Dayron.TeslaAdapterTest do
     assert {:ok, %Dayron.Response{status_code: 500, body: _}} = response
   end
 
-  @tag skip: "TBD"
   test "returns an error for invalid server" do
     response = TeslaAdapter.get("http://localhost:0001/resources/error")
     assert {:error, %Dayron.ClientError{reason: :econnrefused}} = response

From 25fdfada6214aa87c832df394740a2af20c103e9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Tue, 11 Oct 2016 17:35:03 +0200
Subject: [PATCH 08/18] Encode to JSON with Tesla + use maps for headers

---
 lib/dayron/adapters/tesla_adapter.ex            | 9 +++++----
 test/lib/dayron/adapters/tesla_adapter_test.exs | 1 -
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/lib/dayron/adapters/tesla_adapter.ex b/lib/dayron/adapters/tesla_adapter.ex
index ca38635..f832a2f 100644
--- a/lib/dayron/adapters/tesla_adapter.ex
+++ b/lib/dayron/adapters/tesla_adapter.ex
@@ -22,6 +22,7 @@ defmodule Dayron.TeslaAdapter do
     # returning errors along with raw output and perhaps allowing a force
     # flag to ignore content-type header contents, we could use that instead
     # of our own custom decoding. Perhaps a pull request would do it..
+    plug Tesla.Middleware.EncodeJson, engine: Poison
 
     adapter Tesla.Adapter.Hackney
   end
@@ -32,7 +33,7 @@ defmodule Dayron.TeslaAdapter do
   def get(url, headers \\ [], opts \\ []) do
     query = Keyword.get(opts, :params, [])
     try do
-      Client.get(url, headers: headers, query: query) |> translate_response
+      Client.get(url, headers: Enum.into(headers, %{}), query: query) |> translate_response
     rescue
       e in Tesla.Error -> translate_error(e)
     end
@@ -42,21 +43,21 @@ defmodule Dayron.TeslaAdapter do
   Implementation for `Dayron.Adapter.post/4`.
   """
   def post(url, body, headers \\ [], opts \\ []) do
-    Client.post(url, body, headers: headers) |> translate_response
+    Client.post(url, body, headers: Enum.into(headers, %{})) |> translate_response
   end
 
   @doc """
   Implementation for `Dayron.Adapter.patch/4`.
   """
   def patch(url, body, headers \\ [], opts \\ []) do
-    Client.patch(url, body, headers: headers) |> translate_response
+    Client.patch(url, body, headers: Enum.into(headers, %{})) |> translate_response
   end
 
   @doc """
   Implementation for `Dayron.Adapter.delete/3`.
   """
   def delete(url, headers \\ [], opts \\ []) do
-    Client.delete(url, headers: headers) |> translate_response
+    Client.delete(url, headers: Enum.into(headers, %{})) |> translate_response
   end
 
   defp translate_response(%Tesla.Env{} = response) do
diff --git a/test/lib/dayron/adapters/tesla_adapter_test.exs b/test/lib/dayron/adapters/tesla_adapter_test.exs
index 14c464d..b757d41 100644
--- a/test/lib/dayron/adapters/tesla_adapter_test.exs
+++ b/test/lib/dayron/adapters/tesla_adapter_test.exs
@@ -102,7 +102,6 @@ defmodule Dayron.TeslaAdapterTest do
     assert {:error, %Dayron.ClientError{reason: :econnrefused}} = response
   end
 
-  @tag skip: "TBD"
   test "returns a decoded body for a valid post request", %{bypass: bypass, api_url: api_url} do
     Bypass.expect bypass, fn conn ->
       assert "/resources" == conn.request_path

From 4a4e44204b79a3f87bba37acd1c0024f1d0ce6b0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Tue, 11 Oct 2016 17:51:32 +0200
Subject: [PATCH 09/18] Make sure patch requests are properly handled

---
 test/lib/dayron/adapters/tesla_adapter_test.exs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/test/lib/dayron/adapters/tesla_adapter_test.exs b/test/lib/dayron/adapters/tesla_adapter_test.exs
index b757d41..3f91362 100644
--- a/test/lib/dayron/adapters/tesla_adapter_test.exs
+++ b/test/lib/dayron/adapters/tesla_adapter_test.exs
@@ -115,7 +115,6 @@ defmodule Dayron.TeslaAdapterTest do
     assert body[:age] == 30
   end
 
-  @tag skip: "TBD"
   test "returns a decoded body for a valid patch request", %{bypass: bypass, api_url: api_url} do
     Bypass.expect bypass, fn conn ->
       assert "/resources/id" == conn.request_path

From b69bf5bb1811c662a48daf27651fae125c9b1541 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Tue, 11 Oct 2016 17:55:09 +0200
Subject: [PATCH 10/18] Convert empty response body to nil

---
 lib/dayron/adapters/tesla_adapter.ex            | 1 +
 test/lib/dayron/adapters/tesla_adapter_test.exs | 1 -
 2 files changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/dayron/adapters/tesla_adapter.ex b/lib/dayron/adapters/tesla_adapter.ex
index f832a2f..ba6fc0e 100644
--- a/lib/dayron/adapters/tesla_adapter.ex
+++ b/lib/dayron/adapters/tesla_adapter.ex
@@ -73,6 +73,7 @@ defmodule Dayron.TeslaAdapter do
     {:error, struct(Dayron.ClientError, data)}
   end
 
+  defp translate_response_body(""), do: nil
   defp translate_response_body("ok"), do: %{}
   defp translate_response_body(body) do
     try do
diff --git a/test/lib/dayron/adapters/tesla_adapter_test.exs b/test/lib/dayron/adapters/tesla_adapter_test.exs
index 3f91362..15a3e5e 100644
--- a/test/lib/dayron/adapters/tesla_adapter_test.exs
+++ b/test/lib/dayron/adapters/tesla_adapter_test.exs
@@ -128,7 +128,6 @@ defmodule Dayron.TeslaAdapterTest do
     assert body[:age] == 30
   end
 
-  @tag skip: "TBD"
   test "returns an empty body for a valid delete request", %{bypass: bypass, api_url: api_url} do
     Bypass.expect bypass, fn conn ->
       assert "/resources/id" == conn.request_path

From aff50ee1028bce558ce1f3a5737cac05b824a7f8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Tue, 11 Oct 2016 18:20:07 +0200
Subject: [PATCH 11/18] Use Tesla middleware for response translation

---
 lib/dayron/adapters/tesla_adapter.ex | 68 +++++++++++++++++-----------
 1 file changed, 41 insertions(+), 27 deletions(-)

diff --git a/lib/dayron/adapters/tesla_adapter.ex b/lib/dayron/adapters/tesla_adapter.ex
index ba6fc0e..d3fa001 100644
--- a/lib/dayron/adapters/tesla_adapter.ex
+++ b/lib/dayron/adapters/tesla_adapter.ex
@@ -23,17 +23,54 @@ defmodule Dayron.TeslaAdapter do
     # flag to ignore content-type header contents, we could use that instead
     # of our own custom decoding. Perhaps a pull request would do it..
     plug Tesla.Middleware.EncodeJson, engine: Poison
+    plug Dayron.TeslaAdapter.Translator
 
     adapter Tesla.Adapter.Hackney
   end
 
+  defmodule Translator do
+    @moduledoc """
+    A Tesla Middleware implementation, translating responses to the format
+    expected by Dayron.
+    """
+    def call(env, next, opts \\ []) do
+      env
+      |> Tesla.run(next)
+      |> translate_response()
+    end
+
+    defp translate_response(%Tesla.Env{} = response) do
+      {:ok, %Dayron.Response{
+          status_code: response.status,
+          body: translate_response_body(response.body),
+          headers: response.headers |> Map.to_list
+        }
+      }
+    end
+    defp translate_response({:error, response}) do
+      data = response |> Map.from_struct
+      {:error, struct(Dayron.ClientError, data)}
+    end
+
+    defp translate_response_body(""), do: nil
+    defp translate_response_body("ok"), do: %{}
+    defp translate_response_body(body) do
+      try do
+        body |> Poison.decode!(keys: :atoms)
+      rescue
+        Poison.SyntaxError -> body
+      end
+    end
+  end
+
   @doc """
   Implementation for `Dayron.Adapter.get/3`.
   """
   def get(url, headers \\ [], opts \\ []) do
     query = Keyword.get(opts, :params, [])
+    # TODO: Implement try..catch for remaining functions?
     try do
-      Client.get(url, headers: Enum.into(headers, %{}), query: query) |> translate_response
+      Client.get(url, headers: Enum.into(headers, %{}), query: query)
     rescue
       e in Tesla.Error -> translate_error(e)
     end
@@ -43,44 +80,21 @@ defmodule Dayron.TeslaAdapter do
   Implementation for `Dayron.Adapter.post/4`.
   """
   def post(url, body, headers \\ [], opts \\ []) do
-    Client.post(url, body, headers: Enum.into(headers, %{})) |> translate_response
+    Client.post(url, body, headers: Enum.into(headers, %{}))
   end
 
   @doc """
   Implementation for `Dayron.Adapter.patch/4`.
   """
   def patch(url, body, headers \\ [], opts \\ []) do
-    Client.patch(url, body, headers: Enum.into(headers, %{})) |> translate_response
+    Client.patch(url, body, headers: Enum.into(headers, %{}))
   end
 
   @doc """
   Implementation for `Dayron.Adapter.delete/3`.
   """
   def delete(url, headers \\ [], opts \\ []) do
-    Client.delete(url, headers: Enum.into(headers, %{})) |> translate_response
-  end
-
-  defp translate_response(%Tesla.Env{} = response) do
-    {:ok, %Dayron.Response{
-        status_code: response.status,
-        body: translate_response_body(response.body),
-        headers: response.headers |> Map.to_list
-      }
-    }
-  end
-  defp translate_response({:error, response}) do
-    data = response |> Map.from_struct
-    {:error, struct(Dayron.ClientError, data)}
-  end
-
-  defp translate_response_body(""), do: nil
-  defp translate_response_body("ok"), do: %{}
-  defp translate_response_body(body) do
-    try do
-      body |> Poison.decode!(keys: :atoms)
-    rescue
-      Poison.SyntaxError -> body
-    end
+    Client.delete(url, headers: Enum.into(headers, %{}))
   end
 
   defp translate_error(%Tesla.Error{reason: reason}) do

From b542bbe0a5c908de822a866df917b2870f172afd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Wed, 12 Oct 2016 08:52:29 +0200
Subject: [PATCH 12/18] Unify error translation and wrap all Tesla calls

---
 lib/dayron/adapters/tesla_adapter.ex | 29 +++++++++++++++-------------
 1 file changed, 16 insertions(+), 13 deletions(-)

diff --git a/lib/dayron/adapters/tesla_adapter.ex b/lib/dayron/adapters/tesla_adapter.ex
index d3fa001..07686de 100644
--- a/lib/dayron/adapters/tesla_adapter.ex
+++ b/lib/dayron/adapters/tesla_adapter.ex
@@ -48,8 +48,7 @@ defmodule Dayron.TeslaAdapter do
       }
     end
     defp translate_response({:error, response}) do
-      data = response |> Map.from_struct
-      {:error, struct(Dayron.ClientError, data)}
+      translate_error(response)
     end
 
     defp translate_response_body(""), do: nil
@@ -61,6 +60,11 @@ defmodule Dayron.TeslaAdapter do
         Poison.SyntaxError -> body
       end
     end
+
+    def translate_error(%Tesla.Error{} = error) do
+      data = error |> Map.from_struct
+      {:error, struct(Dayron.ClientError, data)}
+    end
   end
 
   @doc """
@@ -68,36 +72,35 @@ defmodule Dayron.TeslaAdapter do
   """
   def get(url, headers \\ [], opts \\ []) do
     query = Keyword.get(opts, :params, [])
-    # TODO: Implement try..catch for remaining functions?
-    try do
-      Client.get(url, headers: Enum.into(headers, %{}), query: query)
-    rescue
-      e in Tesla.Error -> translate_error(e)
-    end
+    tesla_call(:get, [url, [headers: Enum.into(headers, %{}), query: query]])
   end
 
   @doc """
   Implementation for `Dayron.Adapter.post/4`.
   """
   def post(url, body, headers \\ [], opts \\ []) do
-    Client.post(url, body, headers: Enum.into(headers, %{}))
+    tesla_call(:post, [url, body, [headers: Enum.into(headers, %{})]])
   end
 
   @doc """
   Implementation for `Dayron.Adapter.patch/4`.
   """
   def patch(url, body, headers \\ [], opts \\ []) do
-    Client.patch(url, body, headers: Enum.into(headers, %{}))
+    tesla_call(:patch, [url, body, [headers: Enum.into(headers, %{})]])
   end
 
   @doc """
   Implementation for `Dayron.Adapter.delete/3`.
   """
   def delete(url, headers \\ [], opts \\ []) do
-    Client.delete(url, headers: Enum.into(headers, %{}))
+    tesla_call(:delete, [url, [headers: Enum.into(headers, %{})]])
   end
 
-  defp translate_error(%Tesla.Error{reason: reason}) do
-    {:error, %Dayron.ClientError{reason: reason}}
+  defp tesla_call(method, args) do
+    try do
+      apply(Client, method, args)
+    rescue
+      e in Tesla.Error -> Translator.translate_error(e)
+    end
   end
 end

From bd051db9090fa197688be50dd2e0ff1a1818746c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Wed, 12 Oct 2016 15:50:30 +0200
Subject: [PATCH 13/18] Use Elixir 1.3 in CI, required for Tesla

---
 .travis.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.travis.yml b/.travis.yml
index 10040d4..ef44c1d 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,6 @@
 language: elixir
 elixir:
-  - 1.2.3
+  - 1.3.4
 otp_release:
   - 18.2.1
 env:

From a9031815914ea2b72eb688430ff2d975f218e42f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Wed, 12 Oct 2016 16:10:28 +0200
Subject: [PATCH 14/18] Update Tesla adapter docs + add remaining TODO items

---
 lib/dayron/adapters/tesla_adapter.ex | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/lib/dayron/adapters/tesla_adapter.ex b/lib/dayron/adapters/tesla_adapter.ex
index 07686de..3356bb9 100644
--- a/lib/dayron/adapters/tesla_adapter.ex
+++ b/lib/dayron/adapters/tesla_adapter.ex
@@ -7,6 +7,11 @@ defmodule Dayron.TeslaAdapter do
       config :my_app, MyApp.Repo,
         adapter: Dayron.TeslaAdapter,
         url: "https://api.example.com"
+
+  ## TODO
+
+  - Handle options to the Tesla client, see `Dayron.Adapter`
+  - Check test coverage
   """
   @behaviour Dayron.Adapter
 
@@ -18,10 +23,6 @@ defmodule Dayron.TeslaAdapter do
     """
     use Tesla
 
-    # TODO: If the Tesla JSON decoding was a bit more flexible, properly
-    # returning errors along with raw output and perhaps allowing a force
-    # flag to ignore content-type header contents, we could use that instead
-    # of our own custom decoding. Perhaps a pull request would do it..
     plug Tesla.Middleware.EncodeJson, engine: Poison
     plug Dayron.TeslaAdapter.Translator
 
@@ -32,6 +33,12 @@ defmodule Dayron.TeslaAdapter do
     @moduledoc """
     A Tesla Middleware implementation, translating responses to the format
     expected by Dayron.
+
+    We're also doing JSON decoding of responses here, as the built-in JSON
+    middleware in Tesla will only decode content-type `application/json`, as
+    well as raise an error on decoding issues instead of returning the raw
+    input. Both of these differences break the existing implicit contract, as
+    implemented by `Dayron.HTTPoisonAdapter`.
     """
     def call(env, next, opts \\ []) do
       env

From ec400413b9e7146cb472cd37727df38d237f707b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Thu, 13 Oct 2016 07:00:35 +0200
Subject: [PATCH 15/18] Tesla always raises on error; don't handle {:error, _}
 results

---
 lib/dayron/adapters/tesla_adapter.ex | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/lib/dayron/adapters/tesla_adapter.ex b/lib/dayron/adapters/tesla_adapter.ex
index 3356bb9..6fb84c7 100644
--- a/lib/dayron/adapters/tesla_adapter.ex
+++ b/lib/dayron/adapters/tesla_adapter.ex
@@ -11,7 +11,6 @@ defmodule Dayron.TeslaAdapter do
   ## TODO
 
   - Handle options to the Tesla client, see `Dayron.Adapter`
-  - Check test coverage
   """
   @behaviour Dayron.Adapter
 
@@ -54,9 +53,6 @@ defmodule Dayron.TeslaAdapter do
         }
       }
     end
-    defp translate_response({:error, response}) do
-      translate_error(response)
-    end
 
     defp translate_response_body(""), do: nil
     defp translate_response_body("ok"), do: %{}

From 30429546b1aa691d4c1b4190e665c3d1d4fdd63c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Fri, 14 Oct 2016 07:28:16 +0200
Subject: [PATCH 16/18] Handle Hackney options for Tesla

---
 lib/dayron/adapters/tesla_adapter.ex | 41 +++++++++++++++++++++++-----
 1 file changed, 34 insertions(+), 7 deletions(-)

diff --git a/lib/dayron/adapters/tesla_adapter.ex b/lib/dayron/adapters/tesla_adapter.ex
index 6fb84c7..6009da8 100644
--- a/lib/dayron/adapters/tesla_adapter.ex
+++ b/lib/dayron/adapters/tesla_adapter.ex
@@ -10,7 +10,7 @@ defmodule Dayron.TeslaAdapter do
 
   ## TODO
 
-  - Handle options to the Tesla client, see `Dayron.Adapter`
+  - Handle streaming
   """
   @behaviour Dayron.Adapter
 
@@ -39,7 +39,7 @@ defmodule Dayron.TeslaAdapter do
     input. Both of these differences break the existing implicit contract, as
     implemented by `Dayron.HTTPoisonAdapter`.
     """
-    def call(env, next, opts \\ []) do
+    def call(env, next, _opts) do
       env
       |> Tesla.run(next)
       |> translate_response()
@@ -74,29 +74,28 @@ defmodule Dayron.TeslaAdapter do
   Implementation for `Dayron.Adapter.get/3`.
   """
   def get(url, headers \\ [], opts \\ []) do
-    query = Keyword.get(opts, :params, [])
-    tesla_call(:get, [url, [headers: Enum.into(headers, %{}), query: query]])
+    tesla_call(:get, [url, build_options(headers, opts)])
   end
 
   @doc """
   Implementation for `Dayron.Adapter.post/4`.
   """
   def post(url, body, headers \\ [], opts \\ []) do
-    tesla_call(:post, [url, body, [headers: Enum.into(headers, %{})]])
+    tesla_call(:post, [url, body, build_options(headers, opts)])
   end
 
   @doc """
   Implementation for `Dayron.Adapter.patch/4`.
   """
   def patch(url, body, headers \\ [], opts \\ []) do
-    tesla_call(:patch, [url, body, [headers: Enum.into(headers, %{})]])
+    tesla_call(:patch, [url, body, build_options(headers, opts)])
   end
 
   @doc """
   Implementation for `Dayron.Adapter.delete/3`.
   """
   def delete(url, headers \\ [], opts \\ []) do
-    tesla_call(:delete, [url, [headers: Enum.into(headers, %{})]])
+    tesla_call(:delete, [url, build_options(headers, opts)])
   end
 
   defp tesla_call(method, args) do
@@ -106,4 +105,32 @@ defmodule Dayron.TeslaAdapter do
       e in Tesla.Error -> Translator.translate_error(e)
     end
   end
+
+  def build_options([], opts), do: build_options(opts)
+  def build_options(headers, opts) do
+    build_options([{:headers, Enum.into(headers, %{})} | opts])
+  end
+
+  defp build_options(opts) do
+    Enum.reduce(opts, [{:opts, build_hackney_options(opts)}], fn
+      {:headers, value}, options -> [{:headers, value} | options]
+      {:params, value}, options -> [{:query, value} | options]
+    end)
+  end
+
+  defp build_hackney_options(opts) do
+    Enum.reduce(opts, [], fn
+      {:hackney, extra_opts}, hn_opts    -> hn_opts ++ extra_opts
+      {:timeout, value}, hn_opts         -> [{:connect_timeout, value} | hn_opts]
+      {:recv_timeout, value}, hn_opts    -> [{:recv_timeout, value} | hn_opts]
+      {:proxy, value}, hn_opts           -> [{:proxy, value} | hn_opts]
+      {:proxy_auth, value}, hn_opts      -> [{:proxy_auth, value} | hn_opts]
+      {:ssl, value}, hn_opts             -> [{:ssl_options, value} | hn_opts]
+      {:follow_redirect, value}, hn_opts -> [{:follow_redirect, value} | hn_opts]
+      {:max_redirect, value}, hn_opts    -> [{:max_redirect, value} | hn_opts]
+      #{:stream_to, arg}, hn_opts ->
+      #  [:async, {:stream_to, spawn(module, :transformer, [arg])} | hn_opts]
+      _other, hn_opts -> hn_opts
+    end)
+  end
 end

From 10b0c5010a54daf2c179c2137ac46d3beae1be5b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Tue, 25 Oct 2016 10:37:53 +0200
Subject: [PATCH 17/18] Add test for passing a custom hackney option

---
 lib/dayron/adapters/tesla_adapter.ex          |  1 +
 .../dayron/adapters/tesla_adapter_test.exs    | 20 +++++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/lib/dayron/adapters/tesla_adapter.ex b/lib/dayron/adapters/tesla_adapter.ex
index 6009da8..3e5d348 100644
--- a/lib/dayron/adapters/tesla_adapter.ex
+++ b/lib/dayron/adapters/tesla_adapter.ex
@@ -115,6 +115,7 @@ defmodule Dayron.TeslaAdapter do
     Enum.reduce(opts, [{:opts, build_hackney_options(opts)}], fn
       {:headers, value}, options -> [{:headers, value} | options]
       {:params, value}, options -> [{:query, value} | options]
+      _, options -> options
     end)
   end
 
diff --git a/test/lib/dayron/adapters/tesla_adapter_test.exs b/test/lib/dayron/adapters/tesla_adapter_test.exs
index 15a3e5e..66c7313 100644
--- a/test/lib/dayron/adapters/tesla_adapter_test.exs
+++ b/test/lib/dayron/adapters/tesla_adapter_test.exs
@@ -138,4 +138,24 @@ defmodule Dayron.TeslaAdapterTest do
     response = TeslaAdapter.delete("#{api_url}/resources/id", [{"content-type", "application/json"}])
     assert {:ok, %Dayron.Response{status_code: 204, body: nil}} = response
   end
+
+  test "passing a custom hackney option works", %{bypass: bypass, api_url: api_url} do
+    Bypass.expect bypass, fn conn ->
+      case conn.request_path do
+        "/old" ->
+          conn
+          |> Plug.Conn.put_resp_header("location", "/new")
+          |> Plug.Conn.resp(301, "You are being redirected.")
+          |> Plug.Conn.halt
+        "/new" ->
+          Plug.Conn.resp(conn, 200, "bar")
+      end
+    end
+    response = TeslaAdapter.post("#{api_url}/old", "foo", [], [
+      {:follow_redirect, true},
+      {:hackney, [{:force_redirect, true}]}
+    ])
+    assert {:ok, %Dayron.Response{status_code: 200, body: body}} = response
+    assert body == "bar"
+  end
 end

From 5b68a565e575ac948e3778643f07a3945ff9570d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johan=20W=C3=A4rlander?= <johan@snowflake.nu>
Date: Tue, 25 Oct 2016 11:58:23 +0200
Subject: [PATCH 18/18] Add information about Tesla adapter to the README

---
 README.md | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index f6153d6..a44dd88 100644
--- a/README.md
+++ b/README.md
@@ -150,7 +150,11 @@ Using the configuration you're allowed to set headers that will be sent on every
 
 ### HTTP Client Adapter
 
-Currently the only adapter available is [HTTPoisonAdapter](https://github.com/inaka/Dayron/blob/master/lib/dayron/adapters/httpoison_adapter.ex), which uses [HTTPoison](https://github.com/edgurgel/httpoison) and [hackney](https://github.com/benoitc/hackney) to manage HTTP requests.
+Currently the adapters available are:
+- [HTTPoisonAdapter](https://github.com/inaka/Dayron/blob/master/lib/dayron/adapters/httpoison_adapter.ex), which uses [HTTPoison](https://github.com/edgurgel/httpoison) and [hackney](https://github.com/benoitc/hackney) to manage HTTP requests
+- [TeslaAdapter](https://github.com/inaka/Dayron/blob/master/lib/dayron/adapters/tesla_adapter.ex), which uses [Tesla](https://github.com/teamon/tesla) and [hackney](https://github.com/benoitc/hackney) to manage HTTP requests
+
+**NOTE:** While the HTTPoison adapter accepts the `:stream_to` argument and passes it on to HTTPoison, streaming isn't very well supported yet as it's not handled by the adapter in a generic way. The Tesla adapter currently ignores the option. See [discussion in issue #54](https://github.com/inaka/Dayron/issues/54#issuecomment-253715077).
 
 You can also create your own adapter implementing the [Dyron.Adapter](https://github.com/inaka/Dayron/blob/master/lib/dayron/adapter.ex) behavior, and changing the configuration to something like: