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	diff --git a/README.md b/README.md
	index 1408bf1..170ebf7 100644
	--- a/README.md
	+++ b/README.md
	@@ -1,471 +1,472 @@
	# Tesla

	[![Build Status](https://travis-ci.org/teamon/tesla.svg?branch=master)](https://travis-ci.org/teamon/tesla)
	[![Hex.pm](https://img.shields.io/hexpm/v/tesla.svg)](http://hex.pm/packages/tesla)
	[![Hex.pm](https://img.shields.io/hexpm/dt/tesla.svg)](https://hex.pm/packages/tesla)
	[![Hex.pm](https://img.shields.io/hexpm/dw/tesla.svg)](https://hex.pm/packages/tesla)
	[![codecov](https://codecov.io/gh/teamon/tesla/branch/master/graph/badge.svg)](https://codecov.io/gh/teamon/tesla)
	[![Inline docs](http://inch-ci.org/github/teamon/tesla.svg)](http://inch-ci.org/github/teamon/tesla)

	Tesla is an HTTP client loosely based on [Faraday](https://github.com/lostisland/faraday).
	It embraces the concept of middleware when processing the request/response cycle.

	> Note that this README refers to the `master` branch of Tesla, not the latest
	released version on Hex. See [the documentation](http://hexdocs.pm/tesla) for
	the documentation of the version you're using.

	<hr/>

	## [`0.x` to `1.0` Migration Guide](https://github.com/teamon/tesla/wiki/0.x-to-1.0-Migration-Guide)

	```ex
	defp deps do
	[{:tesla, "1.0.0-beta.1"}]
	end
	```

	[Documentation for 0.x branch](https://github.com/teamon/tesla/tree/0.x)

	<hr/>

	## HTTP Client example

	Define module with `use Tesla` and choose from a variety of middleware.

	```elixir
	defmodule GitHub do
	use Tesla

	plug Tesla.Middleware.BaseUrl, "https://api.github.com"
	plug Tesla.Middleware.Headers, [{"authorization", "token xyz"}]
	plug Tesla.Middleware.JSON

	def user_repos(login) do
	get("/user/" <> login <> "/repos")
	end
	end
	```

	Then use it like this:

	```elixir
	{:ok, response} = GitHub.user_repos("teamon")
	response.status # => 200
	response.body # => [%{…}, …]
	response.headers # => [{"content-type", "application/json"}, ...]
	```

	See below for documentation.

	## Installation

	Add `tesla` as dependency in `mix.exs`

	```elixir
	defp deps do
	[{:tesla, "~> 1.0.0"},
	{:jason, ">= 1.0.0"}] # optional, required by JSON middleware
	end
	```

	## Documentation
	- [Middleware](#middleware)
	- [Runtime middleware](#runtime-middleware)
	- [Adapters](#adapters)
	- [Streaming](#streaming)
	- [Multipart](#multipart)
	- [Testing](#testing)
	- [Writing middleware](#writing-middleware)
	- [Direct usage](#direct-usage)
	- [Cheatsheet](#cheatsheet)
	- [Changelog](https://github.com/teamon/tesla/releases)


	## Middleware
	Tesla is built around the concept of composable middlewares.
	This is very similar to how [Plug Router](https://github.com/elixir-plug/plug#the-plug-router) works.

	#### Basic
	- [`Tesla.Middleware.BaseUrl`](https://hexdocs.pm/tesla/Tesla.Middleware.BaseUrl.html) - set base url
	- [`Tesla.Middleware.Headers`](https://hexdocs.pm/tesla/Tesla.Middleware.Headers.html) - set request headers
	- [`Tesla.Middleware.Query`](https://hexdocs.pm/tesla/Tesla.Middleware.Query.html) - set query parameters
	- [`Tesla.Middleware.Opts`](https://hexdocs.pm/tesla/Tesla.Middleware.Opts.html) - set request options
	- [`Tesla.Middleware.FollowRedirects`](https://hexdocs.pm/tesla/Tesla.Middleware.FollowRedirects.html) - follow 3xx redirects
	- [`Tesla.Middleware.MethodOverride`](https://hexdocs.pm/tesla/Tesla.Middleware.MethodOverride.html) - set X-Http-Method-Override
	- [`Tesla.Middleware.Logger`](https://hexdocs.pm/tesla/Tesla.Middleware.Logger.html) - log requests (method, url, status, time)
	+- [`Tesla.Middleware.KeepRequest`](https://hexdocs.pm/tesla/Tesla.Middleware.KeepRequest.html) - keep request body & headers

	#### Formats
	- [`Tesla.Middleware.FormUrlencoded`](https://hexdocs.pm/tesla/Tesla.Middleware.FormUrlencoded.html) - urlencode POST body parameter, useful for POSTing a map/keyword list
	- [`Tesla.Middleware.JSON`](https://hexdocs.pm/tesla/Tesla.Middleware.JSON.html) - JSON request/response body
	- [`Tesla.Middleware.Compression`](https://hexdocs.pm/tesla/Tesla.Middleware.Compression.html) - gzip & deflate
	- [`Tesla.Middleware.DecodeRels`](https://hexdocs.pm/tesla/Tesla.Middleware.DecodeRels.html) - decode `Link` header into `opts[:rels]` field in response

	#### Auth
	- [`Tesla.Middleware.BasicAuth`](https://hexdocs.pm/tesla/Tesla.Middleware.BasicAuth.html) - HTTP Basic Auth
	- [`Tesla.Middleware.DigestAuth`](https://hexdocs.pm/tesla/Tesla.Middleware.DigestAuth.html) - Digest access authentication

	#### Error handling
	- [`Tesla.Middleware.Timeout`](https://hexdocs.pm/tesla/Tesla.Middleware.Timeout.html) - timeout request after X milliseconds despite of server response
	- [`Tesla.Middleware.Retry`](https://hexdocs.pm/tesla/Tesla.Middleware.Retry.html) - retry few times in case of connection refused
	- [`Tesla.Middleware.Fuse`](https://hexdocs.pm/tesla/Tesla.Middleware.Fuse.html) - fuse circuit breaker integration


	## Runtime middleware

	All HTTP functions (`get`, `post`, etc.) can take a dynamic client function as the first parameter.
	This allow to use convenient syntax for modifying the behaviour in runtime.

	Consider the following case: GitHub API can be accessed using OAuth token authorization.

	We can't use `plug Tesla.Middleware.Headers, [{"authorization", "token here"}]`
	since this would be compiled only once and there is no way to insert dynamic user token.

	Instead, we can use `Tesla.build_client` to create a dynamic middleware function:

	```elixir
	defmodule GitHub do
	# same as above with a slightly change to `user_repos/1`

	def user_repos(client, login) do
	# pass `client` argument to `get` function
	get(client, "/user/" <> login <> "/repos")
	end

	def issues(client \\ %Tesla.Client{}) do
	# default to empty client that will not include runtime token
	get(client, "/issues")
	end

	# build dynamic client based on runtime arguments
	def client(token) do
	Tesla.build_client [
	{Tesla.Middleware.Headers, [{"authorization", "token: " <> token }]}
	]
	end
	end
	```

	and then:

	```elixir
	client = GitHub.client(user_token)
	client \|> GitHub.user_repos("teamon")
	client \|> GitHub.get("/me")

	GitHub.issues()
	client \|> GitHub.issues()
	```

	The `Tesla.build_client` function can take two arguments: `pre` and `post` middleware.
	The first list (`pre`) will be included before any other middleware. In case there is a need
	to inject middleware at the end you can pass a second list (`post`). It will be put just
	before adapter. In fact, one can even dynamically override the adapter.

	For example, a private (per user) cache could be implemented as:

	```elixir
	def new(user) do
	Tesla.build_client [], [
	fn env, next ->
	case my_private_cache.fetch(user, env) do
	{:ok, env} -> {:ok, env} # return cached response
	:error -> Tesla.run(env, next) # make real request
	end
	end
	end
	end
	```


	## Adapters

	Tesla supports multiple HTTP adapter that do the actual HTTP request processing.

	- [`Tesla.Adapter.Httpc`](https://hexdocs.pm/tesla/Tesla.Adapter.Httpc.html) - the default, built-in erlang [httpc](http://erlang.org/doc/man/httpc.html) adapter
	- [`Tesla.Adapter.Hackney`](https://hexdocs.pm/tesla/Tesla.Adapter.Hackney.html) - [hackney](https://github.com/benoitc/hackney), "simple HTTP client in Erlang"
	- [`Tesla.Adapter.Ibrowse`](https://hexdocs.pm/tesla/Tesla.Adapter.Ibrowse.html) - [ibrowse](https://github.com/cmullaparthi/ibrowse), "Erlang HTTP client"

	When using ibrowse or hackney adapters remember to it to the dependencies list in `mix.exs`

	```elixir
	defp deps do
	[{:tesla, "~> 1.0.0"},
	{:jason, ">= 1.0.0"}, # optional, required by JSON middleware
	{:hackney, "~> 1.10"}] # or :ibrowse
	end
	```


	## Streaming

	If adapter supports it, you can pass a [Stream](http://elixir-lang.org/docs/stable/elixir/Stream.html) as body, e.g.:

	```elixir
	defmodule ElasticSearch do
	use Tesla

	plug Tesla.Middleware.BaseUrl, "http://localhost:9200"
	plug Tesla.Middleware.JSON

	def index(records_stream) do
	stream = records_stream \|> Stream.map(fn record -> %{index: [some, data]})
	post("/_bulk", stream)
	end
	end
	```

	Each piece of stream will be encoded as JSON and sent as a new line (conforming to JSON stream format)




	## Multipart

	You can pass a `Tesla.Multipart` struct as the body.


	```elixir
	alias Tesla.Multipart

	mp =
	Multipart.new
	\|> Multipart.add_content_type_param("charset=utf-8")
	\|> Multipart.add_field("field1", "foo")
	\|> Multipart.add_field("field2", "bar", headers: [{"content-id", "1"}, {"content-type", "text/plain"}])
	\|> Multipart.add_file("test/tesla/multipart_test_file.sh")
	\|> Multipart.add_file("test/tesla/multipart_test_file.sh", name: "foobar")
	\|> Multipart.add_file_content("sample file content", "sample.txt")

	{:ok, response} = MyApiClient.post("http://httpbin.org/post", mp)
	```


	## Testing

	You can set the adapter to `Tesla.Mock` in tests.

	```elixir
	# config/test.exs
	# Use mock adapter for all clients
	config :tesla, adapter: Tesla.Mock
	# or only for one
	config :tesla, MyApi, adapter: Tesla.Mock
	```

	Then, mock requests before using your client:


	```elixir
	defmodule MyAppTest do
	use ExUnit.Case

	import Tesla.Mock

	setup do
	mock fn
	%{method: :get, url: "http://example.com/hello"} ->
	%Tesla.Env{status: 200, body: "hello"}
	%{method: :post, url: "http://example.com/world"} ->
	json(%{"my" => "data"})
	end

	:ok
	end

	test "list things" do
	assert {:ok, %Tesla.Env{} = env} = MyApp.get("/hello")
	assert env.status == 200
	assert env.body == "hello"
	end
	end
	```


	## Writing middleware

	A Tesla middleware is a module with `call/3` function, that at some point calls `Tesla.run(env, next)` to process
	the rest of stack.

	```elixir
	defmodule MyMiddleware do
	@behaviour Tesla.Middleware

	def call(env, next, options) do
	env
	\|> do_something_with_request
	\|> Tesla.run(next)
	\|> do_something_with_response
	end
	end
	```

	The arguments are:
	- `env` - `Tesla.Env` instance
	- `next` - middleware continuation stack; to be executed with `Tesla.run(env, next)`
	- `options` - arguments passed during middleware configuration (`plug MyMiddleware, options`)

	There is no distinction between request and response middleware, it's all about executing `Tesla.run/2` function at the correct time.

	For example, a request logger middleware could be implemented like this:

	```elixir
	defmodule Tesla.Middleware.RequestLogger do
	@behaviour Tesla.Middleware

	def call(env, next, _) do
	IO.inspect env # print request env
	Tesla.run(env, next)
	end
	end
	```

	and response logger middleware like this:

	```elixir
	defmodule Tesla.Middleware.ResponseLogger do
	@behaviour Tesla.Middleware

	def call(env, next, _) do
	res = Tesla.run(env, next)
	IO.inspect res # print response env
	res
	end
	end
	```

	See [built-in middlewares](https://github.com/teamon/tesla/tree/master/lib/tesla/middleware) for more examples.

	Middleware should have documentation following this template:

	````elixir
	defmodule Tesla.Middleware.SomeMiddleware do
	@behaviour Tesla.Middleware

	@moduledoc """
	Short description what it does

	Longer description, including e.g. additional dependencies.


	### Example usage
	```
	defmodule MyClient do
	use Tesla

	plug Tesla.Middleware.SomeMiddleware, most: :common, options: "here"
	end
	```

	### Options
	- `:list` - all possible options
	- `:with` - their default values
	"""
	end
	````


	## Direct usage

	You can also use Tesla directly, without creating a client module.
	This however won’t include any middleware.

	```elixir
	# Example get request
	{:ok, response} = Tesla.get("http://httpbin.org/ip")
	response.status # => 200
	response.body # => "{\n "origin": "87.205.72.203"\n}\n"
	response.headers # => [{"Content-Type", "application/json" ...}]


	{:ok, response} = Tesla.get("http://httpbin.org/get", query: [a: 1, b: "foo"])
	response.url # => "http://httpbin.org/get?a=1&b=foo"


	# Example post request
	{:ok, response} = Tesla.post("http://httpbin.org/post", "data", headers: [{"Content-Type", "application/json"}])
	```


	## Cheatsheet


	#### Making requests 101
	```elixir
	# GET /path
	get("/path")

	# GET /path?a=hi&b[]=1&b[]=2&b[]=3
	get("/path", query: [a: "hi", b: [1,2,3]])

	# GET with dynamic client
	get(client, "/path")
	get(client, "/path", query: [page: 3])

	# arguments are the same for GET, HEAD, OPTIONS & TRACE
	head("/path")
	options("/path")
	trace("/path")

	# POST, PUT, PATCH
	post("/path", "some-body-i-used-to-know")
	put("/path", "some-body-i-used-to-know", query: [a: "0"])
	patch("/path", multipart)
	```

	#### Configuring HTTP functions visibility
	```elixir
	# generate only get and post function
	use Tesla, only: ~w(get post)a

	# generate only delete fuction
	use Tesla, only: [:delete]

	# generate all functions except delete and options
	use Tesla, except: [:delete, :options]
	```

	#### Disable docs for HTTP functions
	```elixir
	use Tesla, docs: false
	```

	#### Decode only JSON response (do not encode request)
	```elixir
	plug Tesla.Middleware.DecodeJson
	```

	#### Use other JSON library
	```elixir
	# use JSX
	plug Tesla.Middleware.JSON, engine: JSX, engine_opts: [strict: [:comments]]

	# use custom functions
	plug Tesla.Middleware.JSON, decode: &JSX.decode/1, encode: &JSX.encode/1
	```


	#### Custom middleware
	```elixir
	defmodule Tesla.Middleware.MyCustomMiddleware do
	def call(env, next, options) do
	env
	\|> do_something_with_request
	\|> Tesla.run(next)
	\|> do_something_with_response
	end
	end
	```

	## Contributing

	1. Fork it (https://github.com/teamon/tesla/fork)
	2. Create your feature branch (`git checkout -b my-new-feature`)
	3. Commit your changes (`git commit -am 'Add some feature'`)
	4. Push to the branch (`git push origin my-new-feature`)
	5. Create new Pull Request

	## License

	This project is licensed under the MIT License - see the [LICENSE](LICENSE) file for details

	Copyright (c) 2015-2018 [Tymon Tobolski](http://teamon.eu/about/)
	diff --git a/lib/tesla/middleware/keep_request.ex b/lib/tesla/middleware/keep_request.ex
	new file mode 100644
	index 0000000..a591ec3
	--- /dev/null
	+++ b/lib/tesla/middleware/keep_request.ex
	@@ -0,0 +1,26 @@
	+defmodule Tesla.Middleware.KeepRequest do
	+ @behaviour Tesla.Middleware
	+
	+ @moduledoc """
	+ Store request body & headers into opts.
	+
	+ ### Example
	+ ```
	+ defmodule MyClient do
	+ use Tesla
	+
	+ plug Tesla.Middleware.KeepRequest
	+ end
	+
	+ {:ok, env} = MyClient.post("/", "request-data")
	+ env.body # => "response-data"
	+ env.opts[:req_body] # => "request-data"
	+ ```
	+ """
	+ def call(env, next, _opts) do
	+ env
	+ \|> Tesla.put_opt(:req_body, env.body)
	+ \|> Tesla.put_opt(:req_headers, env.headers)
	+ \|> Tesla.run(next)
	+ end
	+end
	diff --git a/test/tesla/middleware/keep_request_test.exs b/test/tesla/middleware/keep_request_test.exs
	new file mode 100644
	index 0000000..7e55515
	--- /dev/null
	+++ b/test/tesla/middleware/keep_request_test.exs
	@@ -0,0 +1,12 @@
	+defmodule Tesla.Middleware.KeepRequestTest do
	+ use ExUnit.Case
	+
	+ @middleware Tesla.Middleware.KeepRequest
	+
	+ test "put request body & headers into opts" do
	+ env = %Tesla.Env{body: "reqbody", headers: [{"x-request", "header"}]}
	+ assert {:ok, env} = @middleware.call(env, [], [])
	+ assert env.opts[:req_body] == "reqbody"
	+ assert env.opts[:req_headers] == [{"x-request", "header"}]
	+ end
	+end

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