%% -*- erlang-indent-level: 4; indent-tabs-mode: nil; fill-column: 80 -*-
%%% Copyright 2012 Erlware, LLC. All Rights Reserved.
%%%
%%% This file is provided to you under the Apache License,
%%% Version 2.0 (the "License"); you may not use this file
%%% except in compliance with the License. You may obtain
%%% a copy of the License at
%%%
%%% http://www.apache.org/licenses/LICENSE-2.0
%%%
%%% Unless required by applicable law or agreed to in writing,
%%% software distributed under the License is distributed on an
%%% "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
%%% KIND, either express or implied. See the License for the
%%% specific language governing permissions and limitations
%%% under the License.
%%%-------------------------------------------------------------------
%%% @author Eric Merritt <[email protected]>
%%% @copyright 2011 Erlware, LLC.
%%% @doc
%%% A module that provides config parsing and support to the system
%%% @end
%%%-------------------------------------------------------------------
-module(rcl_prv_config).
-behaviour(rcl_provider).
%% API
-export([init/1,
do/1,
format_error/1]).
-include_lib("relcool/include/relcool.hrl").
%%%===================================================================
%%% API
%%%===================================================================
%% @doc Required by the system, but not used in this provider
-spec init(rcl_state:t()) -> {ok, rcl_state:t()} | relcool:error().
init(State) ->
{ok, State}.
%% @doc parse all the configs currently specified in the state,
%% populating the state as a result.
-spec do(rcl_state:t()) ->{ok, rcl_state:t()} | relcool:error().
do(State) ->
case rcl_state:config_file(State) of
[] ->
search_for_dominating_config(State);
undefined ->
search_for_dominating_config(State);
ConfigFile when erlang:is_list(ConfigFile) ->
load_config(ConfigFile, State)
end.
-spec format_error(Reason::term()) -> iolist().
format_error({consult, ConfigFile, Reason}) ->
io_lib:format("Unable to read file ~s: ~s", [ConfigFile,
file:format_error(Reason)]);
format_error({invalid_term, Term}) ->
io_lib:format("Invalid term in config file: ~p", [Term]).
%%%===================================================================
%%% Internal Functions
%%%===================================================================
search_for_dominating_config({ok, Cwd}) ->
ConfigFile = filename:join(Cwd, "relcool.config"),
case ec_file:exists(ConfigFile) of
true ->
{ok, ConfigFile};
false ->
search_for_dominating_config(parent_dir(Cwd))
end;
search_for_dominating_config({error, _}) ->
no_config;
search_for_dominating_config(State0) ->
{ok, Cwd} = file:get_cwd(),
case search_for_dominating_config({ok, Cwd}) of
{ok, Config} ->
%% we need to set the root dir on state as well
{ok, RootDir} = parent_dir(Config),
State1 = rcl_state:root_dir(State0, RootDir),
load_config(Config, rcl_state:config_file(State1, Config));
no_config ->
{ok, State0}
end.
%% @doc Given a directory returns the name of the parent directory.
-spec parent_dir(Filename::string()) ->
{ok, DirName::string()} | {error, no_parent_dir}.
parent_dir(Filename) ->
parent_dir(filename:split(Filename), []).
%% @doc Given list of directories, splits the list and returns all dirs but the
%% last as a path.
-spec parent_dir([string()], [string()]) ->
{ok, DirName::string()} | {error, no_parent_dir}.
parent_dir([_H], []) ->
{error, no_parent_dir};
parent_dir([], []) ->
{error, no_parent_dir};
parent_dir([_H], Acc) ->
{ok, filename:join(lists:reverse(Acc))};
parent_dir([H | T], Acc) ->
parent_dir(T, [H | Acc]).
-spec load_config(file:filename(), rcl_state:t()) ->
{ok, rcl_state:t()} | relcool:error().
load_config(ConfigFile, State) ->
{ok, CurrentCwd} = file:get_cwd(),
ok = file:set_cwd(filename:dirname(ConfigFile)),
Result = case file:consult(ConfigFile) of
{error, Reason} ->
?RCL_ERROR({consult, ConfigFile, Reason});
{ok, Terms} ->
lists:foldl(fun load_terms/2, {ok, State}, Terms)
end,
ok = file:set_cwd(CurrentCwd),
Result.
-spec load_terms(term(), {ok, rcl_state:t()} | relcool:error()) ->
{ok, rcl_state:t()} | relcool:error().
load_terms({default_release, RelName, RelVsn}, {ok, State}) ->
{ok, rcl_state:default_release(State, RelName, RelVsn)};
load_terms({paths, Paths}, {ok, State}) ->
code:add_pathsa([filename:absname(Path) || Path <- Paths]),
{ok, State};
load_terms({providers, Providers0}, {ok, State0}) ->
Providers1 = gen_providers(Providers0, State0),
case Providers1 of
{_, E={error, _}} ->
E;
{Providers3, {ok, State3}} ->
{ok, rcl_state:providers(State3, Providers3)}
end;
load_terms({add_providers, Providers0}, {ok, State0}) ->
Providers1 = gen_providers(Providers0, State0),
case Providers1 of
{_, E={error, _}} ->
E;
{Providers3, {ok, State1}} ->
ExistingProviders = rcl_state:providers(State1),
{ok, rcl_state:providers(State1, ExistingProviders ++ Providers3)}
end;
load_terms({overrides, Overrides0}, {ok, State0}) ->
{ok, rcl_state:overrides(State0, Overrides0)};
load_terms({release, {RelName, Vsn}, Applications}, {ok, State0}) ->
Release0 = rcl_release:new(RelName, Vsn),
case rcl_release:goals(Release0, Applications) of
E={error, _} ->
E;
{ok, Release1} ->
{ok, rcl_state:add_release(State0, Release1)}
end;
load_terms({release, {RelName, Vsn}, {erts, ErtsVsn},
Applications}, {ok, State}) ->
Release0 = rcl_release:erts(rcl_release:new(RelName, Vsn), ErtsVsn),
case rcl_release:goals(Release0, Applications) of
E={error, _} ->
E;
{ok, Release1} ->
{ok, rcl_state:add_release(State, Release1)}
end;
load_terms({sys_config, SysConfig}, {ok, State}) ->
{ok, rcl_state:sys_config(State, filename:absname(SysConfig))};
load_terms({Name, Value}, {ok, State})
when erlang:is_atom(Name) ->
{ok, rcl_state:put(State, Name, Value)};
load_terms(_, Error={error, _}) ->
Error;
load_terms(InvalidTerm, _) ->
?RCL_ERROR({invalid_term, InvalidTerm}).
-spec gen_providers([module()], rcl_state:t()) ->
{[rcl_provider:t()], {ok, rcl_state:t()} | relcool:error()}.
gen_providers(Providers, State) ->
lists:foldl(fun(ProviderName, {Providers1, {ok, State1}}) ->
{Provider, State2} = rcl_provider:new(ProviderName, State1),
{[Provider | Providers1], State2};
(_, E={_, {error, _}}) ->
E
end, {[], {ok, State}}, Providers).
