Adds dialyzer support

This commit adds static analysis tool `dialyzer` to the
list of dependencies. It is required to check, that every
parameter in function calls are in place.

This commit also fixes all found static-typing issues.

This commit also adds `CONCTRIBUTING.md` with the development
instructions. Refs #16

CONTRIBUTING.md

@@ -0,0 +1,31 @@
+# Contributing
+
+## Pull Requests Welcome
+
+1. Fork the project
+2. Create a topic branch
+3. Make logically-grouped commits with clear commit messages
+4. Push commits to your fork
+5. Open a pull request against `recaptcha/master`
+
+## Issues
+
+If you believe there to be a bug, please provide the maintainers with enough
+detail to reproduce or a link to an app exhibiting unexpected behavior. For
+help, please start with Stack Overflow.
+
+## Development and testing
+
+To set up the development environment you would have to follow several steps:
+
+0. setup `elixir`, we are using the latest release, but supporting everything from `1.2`
+1. clone the repo
+2. `mix deps.get && mix compile`
+
+To test if everything is working:
+
+1. `mix test` will run unit-tests
+2. `mix credo --strict` will run linting
+3. `mix dialyzer` will run static analyzer tool to check that everything is fine with your code. It may take some time at the first run
+
+If everything is fine - feel free to submit your code!

README.md

@@ -23,7 +23,7 @@ if you have any problems with migrating.
 ```elixir
   defp deps do
     [
-      {:recaptcha, "~> 2.0"},      
+      {:recaptcha, "~> 2.0"},
     ]
   end
 ```
@@ -76,7 +76,6 @@ Recaptcha provides the `verify/2` method. Below is an example using a Phoenix co
 
 ```elixir
   def create(conn, params) do
-    # some code  
     case Recaptcha.verify(params["g-recaptcha-response"]) do
       {:ok, response} -> do_something
       {:error, errors} -> handle_error
@@ -100,10 +99,7 @@ Option                  | Action
 
 ## Contributing
 
-* Fork the project.
-* Make your feature addition or bug fix. (If you're not sure raise an issue to discuss first)
-* Commit
-* Send me a pull request
+Check out [CONTRIBUTING.md](/CONTRIBUTING.md) if you want to help.
 
 ## License
 

lib/recaptcha.ex

@@ -6,9 +6,9 @@ defmodule Recaptcha do
     for more details.
   """
 
-  alias Recaptcha.Config
+  alias Recaptcha.{Config, Http, Response}
 
-  @http_client Application.get_env(:recaptcha, :http_client, Recaptcha.Http)
+  @http_client Application.get_env(:recaptcha, :http_client, Http)
 
   @doc """
   Verifies a reCAPTCHA response string.
@@ -24,18 +24,20 @@ defmodule Recaptcha do
 
     {:ok, api_response} = Recaptcha.verify("response_string")
   """
-  @spec verify(String.t, Keyword.t) :: {:ok, Recaptcha.Response.t} | {:error, [atom]}
+  @spec verify(String.t, Keyword.t) :: {:ok, Response.t} | {:error, [atom]}
   def verify(response, options \\ []) do
-    case @http_client.request_verification(
+    verification = @http_client.request_verification(
       request_body(response, options),
       Keyword.take(options, [:timeout])
-    ) do
+    )
+
+    case verification do
       {:error, errors} ->
         {:error, errors}
       {:ok, %{"success" => false, "error-codes" => errors}} ->
-        {:error, Enum.map(errors, fn(error) -> atomise_api_error(error) end)}
+        {:error, Enum.map(errors, &atomise_api_error/1)}
       {:ok, %{"success" => true, "challenge_ts" => timestamp, "hostname" => host}} ->
-        {:ok, %Recaptcha.Response{challenge_ts: timestamp, hostname: host}}
+        {:ok, %Response{challenge_ts: timestamp, hostname: host}}
       {:ok, %{"success" => false, "challenge_ts" => _timestamp, "hostname" => _host}} ->
         {:error, [:challenge_failed]}
     end
@@ -55,6 +57,6 @@ defmodule Recaptcha do
   defp atomise_api_error(error) do
     error
     |> String.replace("-", "_")
-    |> String.to_atom
+    |> String.to_existing_atom
   end
 end

lib/recaptcha/config.ex

@@ -6,7 +6,7 @@ defmodule Recaptcha.Config do
   @doc """
   Returns the requested variable
   """
-  @spec get_env(atom, atom, atom | map) :: term
+  @spec get_env(atom, atom, any) :: any
   def get_env(application, key, default \\ nil) do
     application
     |> Application.get_env(key, default)

lib/recaptcha/http.ex

@@ -35,7 +35,7 @@ defmodule Recaptcha.Http do
       remote_ip: "remote_ip"
     })
   """
-  @spec request_verification(map, [timeout: integer]) :: {:ok, map} | {:error, [atom]}
+  @spec request_verification(binary, [timeout: integer]) :: {:ok, map} | {:error, [atom]}
   def request_verification(body, options \\ []) do
     timeout = options[:timeout] || Config.get_env(:recaptcha, :timeout, 5000)
     url = Config.get_env(:recaptcha, :verify_url, @default_verify_url)

lib/recaptcha/template.ex

@@ -10,15 +10,17 @@ defmodule Recaptcha.Template do
   require Elixir.EEx
   alias Recaptcha.Config
 
-  EEx.function_from_file :defp, :render_template, "lib/template.html.eex", [:assigns]
+  EEx.function_from_file :defp, :render_template,
+    "lib/template.html.eex", [:assigns]
 
   @doc """
   Returns a string with reCAPTCHA code
 
   To convert the string to html code, use Phoenix.HTML.Raw/1 method
   """
   def display(options \\ []) do
-    public_key = options[:public_key] || Config.get_env(:recaptcha, :public_key)
-    render_template(public_key: public_key, options: options)
+    public_key = options[:public_key] || Config.get_env(
+      :recaptcha, :public_key)
+    render_template(%{public_key: public_key, options: options})
   end
 end

mix.exs

@@ -21,11 +21,17 @@ defmodule Recaptcha.Mixfile do
         "coveralls.post": :test,
         "coveralls.html": :test,
       ],
+
+      # Dialyzer:
+      dialyzer: [
+        plt_add_deps: :apps_direct,
+        plt_add_apps: [:poison]
+      ]
    ]
   end
 
   def application do
-    [applications: [:logger, :httpoison]]
+    [applications: [:logger, :httpoison, :eex]]
   end
 
   defp description do
@@ -39,8 +45,10 @@ defmodule Recaptcha.Mixfile do
     [
       {:httpoison, "~> 0.11.0"},
       {:poison, "~> 1.5 or ~> 2.0 or ~> 3.0"},
+
       {:credo, "~> 0.6", only: [:dev, :test]},
       {:ex_doc, ">= 0.0.0", only: :dev},
+      {:dialyxir, "~> 0.5", only: [:dev]},
       {:excoveralls, "~> 0.6", only: :test},
     ]
   end

mix.lock

@@ -1,6 +1,7 @@
 %{"bunt": {:hex, :bunt, "0.2.0", "951c6e801e8b1d2cbe58ebbd3e616a869061ddadcc4863d0a2182541acae9a38", [:mix], [], "hexpm"},
   "certifi": {:hex, :certifi, "1.2.1", "c3904f192bd5284e5b13f20db3ceac9626e14eeacfbb492e19583cf0e37b22be", [:rebar3], [], "hexpm"},
   "credo": {:hex, :credo, "0.6.0", "44a82f82b94eeb4ba6092c89b8a6730ca1a3291c7940739d5acc8806d25ac991", [:mix], [{:bunt, "~> 0.2.0", [hex: :bunt, repo: "hexpm", optional: false]}], "hexpm"},
+  "dialyxir": {:hex, :dialyxir, "0.5.0", "5bc543f9c28ecd51b99cc1a685a3c2a1a93216990347f259406a910cf048d1d7", [:mix], [], "hexpm"},
   "earmark": {:hex, :earmark, "1.0.1", "2c2cd903bfdc3de3f189bd9a8d4569a075b88a8981ded9a0d95672f6e2b63141", [:mix], [], "hexpm"},
   "ex_doc": {:hex, :ex_doc, "0.13.0", "aa2f8fe4c6136a2f7cfc0a7e06805f82530e91df00e2bff4b4362002b43ada65", [:mix], [{:earmark, "~> 1.0", [hex: :earmark, repo: "hexpm", optional: false]}], "hexpm"},
   "excoveralls": {:hex, :excoveralls, "0.6.5", "2d3faf8fe40e77c980620f1344f6d3df2c43b18ab9c21a2c1781a898cc710184", [:mix], [{:exjsx, ">= 3.0.0", [hex: :exjsx, repo: "hexpm", optional: false]}, {:hackney, ">= 0.12.0", [hex: :hackney, repo: "hexpm", optional: false]}], "hexpm"},