rebar.config.script

Conf0 = CONFIG,

NovaBranch = list_to_binary(os:getenv("NOVA_BRANCH", "master")),
NovaRepo = os:getenv("NOVA_REPO", "novaframework/nova"),
RepoUrl = "https://github.com/" ++ NovaRepo ++ ".git",

NovaDep = case NovaBranch of
            <<"master">> ->
              {nova, ".*", {git, RepoUrl, {branch, "master"}}};
            <<"refs/tags/", Rest/binary>> ->
              {nova, ".*", {git, RepoUrl, {tag, binary_to_list(Rest)}}};
            NovaBranch ->
              {nova, ".*", {git, RepoUrl, {branch, binary_to_list(NovaBranch)}}}
          end,

%% Get existing deps from rebar.config (minus nova which we override)
ExistingDeps = case proplists:get_value(deps, Conf0) of
                   undefined -> [];
                   Deps0 -> [D || D <- Deps0, element(1, D) =/= nova]
               end,

Deps = {deps, [NovaDep | ExistingDeps]},
Conf1 = proplists:delete(deps, Conf0),

[Deps|Conf1].