Mojito

Mojito is an easy-to-use HTTP client built using the low-level Mint library.

It provides an interface that will feel familiar to users of other Elixir HTTP client libraries.

HTTPS, one-off requests, connection pooling, and request pipelining are supported out of the box. Mojito supports the same process-less architecture as Mint; i.e., it does not spawn a process per request.

Installation

Add mojito to your deps in mix.exs:

{:mojito, "~> 0.2.2"}

Single-request example

Mojito.request/1 or the equivalent Mojito.request/5 can be used directly for making individual requests:

>>>> Mojito.request(:get, "https://jsonplaceholder.typicode.com/posts/1")
{:ok,
 %Mojito.Response{
   body: "{\n  \"userId\": 1,\n  \"id\": 1,\n  \"title\": \"sunt aut facere repellat provident occaecati excepturi optio reprehenderit\",\n  \"body\": \"quia et suscipit\\nsuscipit recusandae consequuntur expedita et cum\\nreprehenderit molestiae ut ut quas totam\\nnostrum rerum est autem sunt rem eveniet architecto\"\n}",
   headers: [
     {"content-type", "application/json; charset=utf-8"},
     {"content-length", "292"},
     {"connection", "keep-alive"},
     ...
   ],
   status_code: 200
 }}

Mojito.request does not spawn any additional processes to handle the HTTP response; TCP messages are received and handled within the caller process. In the common case, this results in faster performance and lower overhead in the Erlang VM.

However, if the caller is also expecting to receive other messages at the same time, this can cause conflict. In this case, it’s recommended to wrap the call to Mojito.request in Task.async/1:

>>>> task = Task.async(fn () -> Mojito.request(:get, "https://jsonplaceholder.typicode.com/posts/1") end)
>>>> Task.await(task)
{:ok,
 %Mojito.Response{
   body: "{\n  \"userId\": 1,\n  \"id\": 1,\n  \"title\": \"sunt aut facere repellat provident occaecati excepturi optio reprehenderit\",\n  \"body\": \"quia et suscipit\\nsuscipit recusandae consequuntur expedita et cum\\nreprehenderit molestiae ut ut quas totam\\nnostrum rerum est autem sunt rem eveniet architecto\"\n}",
   headers: [
     {"content-type", "application/json; charset=utf-8"},
     {"content-length", "292"},
     {"connection", "keep-alive"},
     ...
   ],
   status_code: 200
 }}

Pool example

Mojito.Pool.request/2 or the equivalent Mojito.Pool.request/6 can be used when a pool of persistent HTTP connections is desired:

>>>> children = [Mojito.Pool.child_spec(MyPool)]
>>>> {:ok, _pid} = Supervisor.start_link(children, strategy: :one_for_one)
>>>> Mojito.Pool.request(MyPool, :get, "http://example.com")
{:ok, %Mojito.Response{...}}

Connection pooling in Mojito is implemented using Poolboy.

Currently, Mojito connection pools should only be used to access a single protocol + hostname + port destination; otherwise, connections are reused only sporadically.

Self-signed SSL/TLS certificates

To accept self-signed certificates in HTTPS connections, you can give the transport_opts: [verify: :verify_none] option to Mojito.request or Mojito.Pool.request:

>>>> Mojito.request(:get, "https://localhost:8443/")
{:error, {:tls_alert, 'bad certificate'}}

>>>> Mojito.request(:get, "https://localhost:4443/", [], "", transport_opts: [verify: :verify_none])
{:ok, %Mojito.Response{...}}

Authorship and License

Copyright 2018-2019, Appcues, Inc.

Mojito is released under the MIT License.