HealthCheck

Simple health check library for Elixir applications with support for Ecto, Redix, Kaffe, MongoDB, and S3-compatible storage (Minio).

Dependencies are optional, so you only need to include what you use.

Installation

The package can be installed by adding elixir_health_check to your list of dependencies in mix.exs:

def deps do
  [
    {:elixir_health_check, "~> 0.1.0"}
  ]
end

Usage

Configuration

Configure the checks in your config.exs. The configuration is a keyword list where keys are dependency names and values are their respective configurations.

config :my_app, :health_check_config,
  postgres: [repos: [MyApp.Repo]],
  redis: [redis_conn_selector: fn -> MyApp.Redis.get_conn() end],
  kafka: [],
  mongo: [topology: :my_mongo_topology],
  endpoint: [endpoint: "http://minio:9000/minio/health/live"]

The library provides default checkers for:

• :postgres (requires :repos)
• :redis (requires :redis_conn_selector)
• :kafka (optional :endpoints)
• :mongo (requires :topology)
• :endpoint (requires :endpoint)

Postgres Check

Verifies connectivity to one or more Ecto repositories by executing SELECT 1.

Redis Check

Verifies connectivity to Redis by sending a PING command. You must provide a function that returns a connection (pid or atom).

Kafka Check

The Kafka check verifies that the kaffe application is running and attempts to list topics from the configured endpoints using :brod.

Endpoint Check

The Endpoint check uses HTTPoison to verify connectivity to a specified URL. It expects a status code less than 500.

Mongo Check

The Mongo check uses mongodb_driver to send a ping command to the specified topology.

In a Phoenix/Plug application

You can use HealthCheck.Router as a plug in your endpoint or forward to it in your router:

# In endpoint.ex
plug HealthCheck.Router, otp_app: :my_app

# Or in router.ex
forward "/health", HealthCheck.Router, otp_app: :my_app

In a non-web application

You can start a standalone health check server (using Bandit) in your application’s supervision tree:

def start(_type, _args) do
  children = [
    {HealthCheck.Server, otp_app: :my_app, port: 4000}
    # ... other children
  ]
  Supervisor.start_link(children, strategy: :one_for_one)
end