HackerNewsAggregator

Docker Setup

To start the Application with Docker:

Build

docker build -t hacker-news/aggregator .

Run

docker run --rm -p 4000:4000 --name=aggregator hacker-news/aggregator

Local Setup

To start your Phoenix server in your local env:

Erlang / Elixir

Install Erlang and Elixir - one way to install it is by running asdf install to install the correct version of Erlang and Elixir (if you use asdf as a package manager)

Install dependencies

mix deps.get

Start Phoenix endpoint

mix phx.server or inside IEx with iex -S mix phx.server

Usage

Once the application starts, new stories will be pulled from the Hacker News API and they will be available via two public APIs: JSON over http and JSON over WebSockets.

Now you can now test the application by visiting the following URL from your browser (the data will already be saved in memory (ETS table):

List stories with pagination (10 results per page)

http://localhost:4000/api/v0/top_stories

http://localhost:4000/api/v0/top_stories?page=3

Fetch a single story using the story id

http://localhost:4000/api/v0/get_story/31445753

http://localhost:4000/api/v0/get_story/31452449

You can use a CLI application to test the WebSocket

Use npm install -g wscat in order to get started. Copy the input that is on the > line below.

$ wscat -c 'ws://localhost:4000/socket/websocket?vsn=2.0.0'
connected (press CTRL+C to quit)
> ["1","1","stories:lobby","phx_join",{}]

The WebSockets api should send the 50 top stories right after you joined the stories:lobby

After 5 minutes, the server will poll the Hacker News API again and the top 50 stories will be sent to connected customers and also will be available via HTTP.