Defines and holds configuration for your Elasticsearch cluster.

defmodule MyApp.ElasticsearchCluster do
  use Elasticsearch.Cluster
end

Once you have created your cluster, add it to your application’s supervision tree:

children = [
  MyApp.ElasticsearchCluster
]

Finally, you can issue requests to Elasticsearch using it.

Elasticsearch.get(MyApp.ElasticsearchCluster, "/_cat/health")

Configuration

Clusters can be configured in several ways.

Via Mix

Clusters can read configuration from the mix config, if you pass the :otp_app option:

defmodule MyApp.ElasticsearchCluster do
  use Elasticsearch.Cluster, otp_app: :my_app
end

# In your config/config.exs...
config :my_app, MyApp.ElasticsearchCluster,
  url: "http://localhost:9200",
  # ...

Via init/1

When a cluster starts, you can override its configuration via the init/1 callback. This is a good place to read from environment variables.

defmodule MyApp.ElasticsearchCluster do
  use Elasticsearch.Cluster

  def init(config) do
    config =
      config
      |> Map.put(:url, System.get_env("ELASTICSEARCH_URL"))
      # ...

    {:ok, config}
  end
end

Via start_link/1

You can also pass configuration into the cluster directly when you start it with start_link/1.

MyApp.Elasticsearch.start_link(url: "http://localhost:9200", ...)

Configuration Options

The following options are available for configuration.

• :url - The URL at which the Elasticsearch cluster is available.

• :api - The API module to use to communicate with Elasticsearch. Must implement the Elasticsearch.API behaviour.

• :bulk_page_size - When creating indexes via bulk upload, how many documents to include per request.

• :bulk_wait_interval - The number of milliseconds to wait between bulk upload requests.

• :indexes - A map of indexes. Used by mix elasticsearch.build to build indexes.

  • :settings: The file path of the JSON settings for the index.
  • :store: An Elasticsearch.Store module to use to load data for the index.
  • :sources: A list of sources you want to load for this index.

• :json_library (Optional) - The JSON library to use. (E.g. Poison or Jason)

• :username (Optional) - The HTTP Basic username for the Elasticsearch endpoint, if any.

• :password (Optional) - The HTTP Basic password for the Elasticsearch endpoint, if any.

• :default_headers (Optional) - A list of default headers to send with the each request.

• :default_options (Optional) - A list of default HTTPoison/Hackney options to send with each request.

Configuration Example

%{
  api: Elasticsearch.API.HTTP,
  json_library: Poison,
  url: "http://localhost:9200",
  username: "username",
  password: "password",
  default_headers: [{"authorization", "custom-value"}],
  default_options: [ssl: [{:versions, [:'tlsv1.2']}],
  indexes: %{
    posts: %{
      settings: "priv/elasticsearch/posts.json",
      store: MyApp.ElasticsearchStore,
      sources: [MyApp.Post],
      bulk_page_size: 5000,
      bulk_wait_interval: 5000
    }
  }
}