Hui.Http behaviour (Hui v0.10.4) View Source

A behaviour module for handling HTTP requests and responses.

This module is responsible for dispatching Solr request encapsulated in Hui.Http.t/0 struct. It underpins the core functions of Hui, as well as provides default implementation and built-in HTTP client capability based on Erlang httpc.

Using other HTTP clients

Instead of using the built-in client, other HTTP clients may be developed by implementing Hui.Http behaviour and deployed through application configuration. For example, Hui provides another client option - Hui.Http.Httpoison.

  config :hui,
    http_client: Hui.Http.Httpoison

Hui.Http.Httpoison depends on HTTPoison. The dependency needs to be specified in mix.exs. Add :httpoison to the applications section of the mix file to start up the client for runtime.

  defp deps do
    [
      {:httpoison, "~> 1.7"}
    ]
  end

Link to this section Summary

Types

body()

Request or response body which can be in iodata or parsed (as map) format.

request_url()

The request url in iodata format consisting the full path and encoded query params.

response()

Response tuple from a HTTP request consists of the Hui.Http.t/0 struct and Solr response.

t()

The main request and response data struct.

Functions

dispatch(request)

Dispatch HTTP request to a Solr endpoint using the built-in Erlang httpc client.

dispatch(request, client)

Dispatch HTTP request to a Solr endpoint using a given client implementing the Hui.Http behaviour.

Callbacks

dispatch(request)

Dispatch HTTP request to a Solr endpoint.

Link to this section Types

body()

Specs

body() :: nil | iodata() | map()

Request or response body which can be in iodata or parsed (as map) format.

request_url()

Specs

request_url() :: iodata()

The request url in iodata format consisting the full path and encoded query params.

response()

Specs

response() :: {:ok, t()} | {:error, Hui.Error.t()}

Response tuple from a HTTP request consists of the Hui.Http.t/0 struct and Solr response.

t()

Specs

t() :: %Hui.Http{
  body: body(),
  headers: list(),
  method: :get | :post,
  options: keyword(),
  status: nil | integer(),
  url: request_url()
}

The main request and response data struct.

Link to this section Functions

dispatch(request)

Specs

dispatch(request :: t()) :: response()

Dispatch HTTP request to a Solr endpoint using the built-in Erlang httpc client.

This is a default implementation of dispatch/1 callback based on httpc.

Example

  request = %Hui.Http{
              url: ["http://localhost:8080/solr/select", "?", "q=loch"],
              headers: [{"accept", "application/json"}],
              options: [{:timeout, 1000}]
            }

  {:ok, response} = HTTP.dispatch(request)

Find out more about the available options from httpc documentation.

dispatch(request, client)

Specs

dispatch(request :: t(), client :: module()) :: response()

Dispatch HTTP request to a Solr endpoint using a given client implementing the Hui.Http behaviour.

Same as dispatch/1 but invoking request through dynamic dispatching. See Hui.Http.Httpoison for a reference client implementation based on HTTPoison that provides additional options such as connection pooling.

Link to this section Callbacks

dispatch(request)

(optional)

Specs

dispatch(request :: t()) :: response()

Dispatch HTTP request to a Solr endpoint.

This callback is optional and can be used to adapt other HTTP clients to provide different HTTP options and performance. Hui provides Hui.Http.Httpoison, a reference implementation of this callback that can be used in conjunction with dispatch/2.

If the callback is not implemented, the default built-in httpc-based client will be used.