avlizer

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%%% Copyright (c) 2018 Klarna AB
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-module(avlizer).

%% application callbacks
-export([ start/2
        , stop/1
        ]).

start(_StartType, _StartArgs) ->
  case osenv("AVLIZER_CONFLUENT_SCHEMAREGISTRY_URL", false) of
    false -> ok;
    URL ->
      Vars0 = application:get_env(?APPLICATION, avlizer_confluent, #{}),
      Vars = Vars0#{schema_registry_url => URL},
      application:set_env(?APPLICATION, avlizer_confluent, Vars)
  end,
  avlizer_sup:start_link().

stop(_State) -> ok.

osenv(Name, Default) ->
  case os:getenv(Name) of
    "" -> Default; %% VAR=""
    false -> Default; %% not set
    Val -> Val
  end.

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