Coinbase Price Watcher

Build

$ rebar3 compile

Run

$ chromium-browser --remote-debugging-port=9222
$ ERL_FLAGS="-args_file env/local.vmargs" rebar3 shell

Usage

> coinbase_price_watcher:get_products().

[<<"AAVE-EUR">>,<<"AAVE-USD">>,<<"ALGO-USD">>,
 <<"ATOM-USD">>,<<"BAND-GBP">>,<<"BAT-ETH">>,<<"BCH-EUR">>,
 <<"BCH-USD">>,<<"BNT-USD">>,<<"BTC-USD">>,<<"CGLD-USD">>,
 <<"CVC-USDC">>,<<"DAI-USD">>,<<"DNT-USDC">>,<<"ETH-BTC">>,
 <<"ETH-EUR">>,<<"ETH-USD">>,<<"ETH-USDC">>,<<"FIL-USD">>,
 <<"GRT-USD">>,<<"LINK-BTC">>,<<"LINK-ETH">>,<<"LINK-EUR">>,
 <<"LINK-GBP">>,<<"LINK-USD">>,<<"LOOM-USDC">>,<<"LTC-USD">>,
 <<"MANA"...>>,<<...>>|...]

    
> coinbase_price_watcher:get_prices(<<"BTC-USD">>).
  
{ok,[#{<<"price">> => <<"35810.84">>,
        <<"time">> => <<"2021-01-17T19:40:53.580857Z">>},
    #{<<"price">> => <<"35809.66">>,
        <<"time">> => <<"2021-01-17T19:40:55.396850Z">>},
    ...
    ]}

> coinbase_price_watcher:subscribe(<<"BTC-USD">>).

{ok,[#{<<"price">> => <<"35810.84">>,
        <<"time">> => <<"2021-01-17T19:40:53.580857Z">>},
    #{<<"price">> => <<"35809.66">>,
        <<"time">> => <<"2021-01-17T19:40:55.396850Z">>},
    ...
    ]}
    
> flush().
Shell got {ws_received,#{<<"price">> => <<"35809.76">>,
                         <<"type">> => <<"price_changed">>,
                         <<"product_id">> => <<"BTC-USD">>,
                         <<"time">> => <<"2021-01-17T19:42:50.457866Z">>}}
Shell got {ws_received,#{<<"price">> => <<"35809.76">>,
                         <<"type">> => <<"price_changed">>,
                         <<"product_id">> => <<"BTC-USD">>,
                         <<"time">> => <<"2021-01-17T19:42:50.457866Z">>}}

> coinbase_price_watcher:unsubscribe(<<"BTC-USD">>).
ok