%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
%% ex: ts=4 sw=4 et
%% -------------------------------------------------------------------
%%
%% rebar: Erlang Build Tools
%%
%% Copyright (c) 2011 Trifork
%%
%% Permission is hereby granted, free of charge, to any person obtaining a copy
%% of this software and associated documentation files (the "Software"), to deal
%% in the Software without restriction, including without limitation the rights
%% to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
%% copies of the Software, and to permit persons to whom the Software is
%% furnished to do so, subject to the following conditions:
%%
%% The above copyright notice and this permission notice shall be included in
%% all copies or substantial portions of the Software.
%%
%% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
%% IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
%% FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
%% AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
%% LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
%% OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
%% THE SOFTWARE.
%% -------------------------------------------------------------------
-module(rebar_prv_shell).
-author("Kresten Krab Thorup <krab@trifork.com>").
-author("Fred Hebert <mononcqc@ferd.ca>").
-behaviour(provider).
-export([init/1,
do/1,
format_error/1]).
-include("rebar.hrl").
-include_lib("providers/include/providers.hrl").
-define(PROVIDER, shell).
-define(DEPS, [compile]).
-dialyzer({nowarn_function, rewrite_leaders/2}).
%% ===================================================================
%% Public API
%% ===================================================================
-spec init(rebar_state:t()) -> {ok, rebar_state:t()}.
init(State) ->
State1 = rebar_state:add_provider(
State,
providers:create([
{name, ?PROVIDER},
{module, ?MODULE},
{bare, true},
{deps, ?DEPS},
{example, "rebar3 shell"},
{short_desc, "Run shell with project apps and deps in path."},
{desc, info()},
{opts, [{config, undefined, "config", string,
"Path to the config file to use. Defaults to "
"{shell, [{config, File}]} and then the relx "
"sys.config file if not specified."},
{name, undefined, "name", atom,
"Gives a long name to the node."},
{sname, undefined, "sname", atom,
"Gives a short name to the node."},
{setcookie, undefined, "setcookie", atom,
"Sets the cookie if the node is distributed."},
{script_file, undefined, "script", string,
"Path to an escript file to run before "
"starting the project apps. Defaults to "
"rebar.config {shell, [{script_file, File}]} "
"if not specified."},
{apps, undefined, "apps", string,
"A list of apps to boot before starting the "
"shell. (E.g. --apps app1,app2,app3) Defaults "
"to rebar.config {shell, [{apps, Apps}]} or "
"relx apps if not specified."},
{relname, $r, "relname", atom,
"Name of the release to use as a template for the "
"shell session"},
{relvsn, $v, "relvsn", string,
"Version of the release to use for the shell "
"session"},
{start_clean, undefined, "start-clean", boolean,
"Cancel any applications in the 'apps' list "
"or release."},
{env_file, undefined, "env-file", string,
"Path to file of os environment variables to setup "
"before expanding vars in config files."},
{user_drv_args, undefined, "user_drv_args", string,
"Arguments passed to user_drv start function for "
"creating custom shells."}]}
])
),
{ok, State1}.
-spec do(rebar_state:t()) -> {ok, rebar_state:t()} | {error, string()}.
do(Config) ->
shell(Config),
{ok, Config}.
-spec format_error(any()) -> iolist().
format_error(Reason) ->
io_lib:format("~p", [Reason]).
%% NOTE:
%% this is an attempt to replicate `erl -pa ./ebin -pa deps/*/ebin`. it is
%% mostly successful but does stop and then restart the user io system to get
%% around issues with rebar being an escript and starting in `noshell` mode.
%% it also lacks the ctrl-c interrupt handler that `erl` features. ctrl-c will
%% immediately kill the script. ctrl-g, however, works fine
shell(State) ->
setup_name(State),
setup_paths(State),
ShellArgs = debug_get_value(shell_args, rebar_state:get(State, shell, []), undefined,
"Found user_drv args from command line option."),
setup_shell(ShellArgs),
maybe_run_script(State),
%% apps must be started after the change in shell because otherwise
%% their application masters never gets the new group leader (held in
%% their internal state)
maybe_boot_apps(State),
simulate_proc_lib(),
true = register(rebar_agent, self()),
{ok, GenState} = rebar_agent:init(State),
%% Hack to fool the init process into thinking we have stopped and the normal
%% node start process can go on. Without it, init:get_status() always return
%% '{starting, started}' instead of '{started, started}'
init ! {'EXIT', self(), normal},
gen_server:enter_loop(rebar_agent, [], GenState, {local, rebar_agent}, hibernate).
info() ->
"Start a shell with project and deps preloaded similar to~n'erl -pa ebin -pa deps/*/ebin'.~n".
setup_shell(ShellArgs) ->
LoggerState = maybe_remove_logger(),
OldUser = kill_old_user(),
%% Test for support here
NewUser = try erlang:open_port({spawn,"tty_sl -c -e"}, []) of
Port when is_port(Port) ->
true = port_close(Port),
setup_new_shell(ShellArgs)
catch
error:_ ->
setup_old_shell()
end,
rewrite_leaders(OldUser, NewUser),
maybe_reset_logger(LoggerState).
%% @private starting with OTP-21.2.3, there's an oddity where the logger
%% likely tries to handle system logs while we take down the TTY, which
%% ends up hanging the default logger. This function (along with
%% `maybe_reset_logger/1') removes and re-adds the default logger before and
%% after the TTY subsystem is taken offline, which prevents such hanging.
maybe_remove_logger() ->
case erlang:function_exported(logger, module_info, 0) of
false ->
ignore;
true ->
{ok, Cfg} = logger:get_handler_config(default),
logger:remove_handler(default),
{restart, Cfg}
end.
maybe_reset_logger(ignore) ->
ok;
maybe_reset_logger({restart, #{module := Mod, config := Cfg}}) ->
logger:add_handler(default, Mod, Cfg).
kill_old_user() ->
OldUser = whereis(user),
%% terminate the current user's port, in a way that makes it shut down,
%% but without taking down the supervision tree so that the escript doesn't
%% fully die
[P] = [P || P <- element(2,process_info(whereis(user), links)), is_port(P)],
user ! {'EXIT', P, normal}, % pretend the port died, then the port can die!
exit(P, kill),
wait_for_port_death(1000, P),
OldUser.
wait_for_port_death(N, _) when N < 0 ->
%% This risks displaying a warning!
whatever;
wait_for_port_death(N, P) ->
case erlang:port_info(P) of
undefined ->
ok;
_ ->
timer:sleep(10),
wait_for_port_death(N-10, P)
end.
setup_new_shell(ShellArgs) ->
%% terminate the current user supervision structure, if any
_ = supervisor:terminate_child(kernel_sup, user),
%% start a new shell (this also starts a new user under the correct group)
case ShellArgs of
undefined ->
_ = user_drv:start();
_ ->
_ = user_drv:start(ShellArgs)
end,
%% wait until user_drv and user have been registered (max 3 seconds)
ok = wait_until_user_started(3000),
whereis(user).
setup_old_shell() ->
%% scan all processes for any with references to the old user and save them to
%% update later
NewUser = rebar_user:start(), % hikack IO stuff with fake user
NewUser = whereis(user),
NewUser.
rewrite_leaders(OldUser, NewUser) ->
%% set any process that had a reference to the old user's group leader to the
%% new user process. Catch the race condition when the Pid exited after the
%% liveness check.
_ = [catch erlang:group_leader(NewUser, Pid)
|| Pid <- erlang:processes(),
proplists:get_value(group_leader, erlang:process_info(Pid)) == OldUser,
is_process_alive(Pid)],
%% Application masters have the same problem, but they hold the old group
%% leader in their state and hold on to it. Re-point the processes whose
%% leaders are application masters. This can mess up a few things around
%% shutdown time, but is nicer than the current lock-up.
OldMasters = [Pid
|| Pid <- erlang:processes(),
Pid < NewUser, % only change old masters
{_,Dict} <- [erlang:process_info(Pid, dictionary)],
{application_master,init,4} == proplists:get_value('$initial_call', Dict)],
_ = [catch erlang:group_leader(NewUser, Pid)
|| Pid <- erlang:processes(),
lists:member(proplists:get_value(group_leader, erlang:process_info(Pid)),
OldMasters)],
try
case erlang:function_exported(logger, module_info, 0) of
false ->
%% Old style logger had a lock-up issue and other problems related
%% to group leader handling.
%% enable error_logger's tty output
error_logger:swap_handler(tty),
%% disable the simple error_logger (which may have been added
%% multiple times). removes at most the error_logger added by
%% init and the error_logger added by the tty handler
remove_error_handler(3),
%% reset the tty handler once more for remote shells
error_logger:swap_handler(tty);
true ->
%% This is no longer a problem with the logger interface
ok
end
catch
?WITH_STACKTRACE(E,R,S) % may fail with custom loggers
?DEBUG("Logger changes failed for ~p:~p (~p)", [E,R,S]),
hope_for_best
end.
setup_paths(State) ->
%% Add deps to path
code:add_pathsa(rebar_state:code_paths(State, all_deps)),
%% add project app test paths
ok = add_test_paths(State).
maybe_run_script(State) ->
case first_value([fun find_script_option/1,
fun find_script_rebar/1], State) of
no_value ->
?DEBUG("No script_file specified.", []),
ok;
"none" ->
?DEBUG("Shell script execution skipped (--script none).", []),
ok;
RelFile ->
File = filename:absname(RelFile),
try run_script_file(File)
catch
?WITH_STACKTRACE(C,E,S)
?ABORT("Couldn't run shell escript ~p - ~p:~p~nStack: ~p",
[File, C, E, S])
end
end.
-spec find_script_option(rebar_state:t()) -> no_value | list().
find_script_option(State) ->
{Opts, _} = rebar_state:command_parsed_args(State),
debug_get_value(script_file, Opts, no_value,
"Found script file from command line option.").
-spec find_script_rebar(rebar_state:t()) -> no_value | list().
find_script_rebar(State) ->
Config = rebar_state:get(State, shell, []),
%% Either a string, or undefined
debug_get_value(script_file, Config, no_value,
"Found script file from rebar config file.").
run_script_file(File) ->
?DEBUG("Extracting escript from ~p", [File]),
{ok, Script} = escript:extract(File, [compile_source]),
Beam = proplists:get_value(source, Script),
Mod = proplists:get_value(module, beam_lib:info(Beam)),
?DEBUG("Compiled escript as ~p", [Mod]),
FakeFile = "/fake_path/" ++ atom_to_list(Mod),
{module, Mod} = code:load_binary(Mod, FakeFile, Beam),
?DEBUG("Evaling ~p:main([]).", [Mod]),
Result = Mod:main([]),
?DEBUG("Result: ~p", [Result]),
Result.
maybe_boot_apps(State) ->
_ = maybe_set_env_vars(State),
case find_apps_to_boot(State) of
undefined ->
%% try to read in sys.config file
ok = reread_config([], State);
Apps ->
%% load apps, then check config, then boot them.
load_apps(Apps),
ok = reread_config(Apps, State),
boot_apps(Apps)
end.
simulate_proc_lib() ->
FakeParent = spawn_link(fun() -> timer:sleep(infinity) end),
put('$ancestors', [FakeParent]),
put('$initial_call', {rebar_agent, init, 1}).
setup_name(State) ->
{Long, Short, Opts} = rebar_dist_utils:find_options(State),
rebar_dist_utils:either(Long, Short, Opts).
find_apps_to_boot(State) ->
%% Try the shell_apps option
case first_value([fun find_apps_option/1,
fun find_apps_rebar/1,
fun find_apps_relx/1], State) of
no_value ->
undefined;
Apps ->
Apps
end.
-spec find_apps_option(rebar_state:t()) -> no_value | [atom()].
find_apps_option(State) ->
{Opts, _} = rebar_state:command_parsed_args(State),
case debug_get_value(apps, Opts, no_value,
"Found shell apps from command line option.") of
no_value ->
case debug_get_value(start_clean, Opts, false,
"Found start-clean argument to disable apps") of
false -> no_value;
true -> []
end;
AppsStr ->
[ list_to_atom(AppStr)
|| AppStr <- rebar_string:lexemes(AppsStr, " ,:") ]
end.
-spec find_apps_rebar(rebar_state:t()) -> no_value | list().
find_apps_rebar(State) ->
ShellOpts = rebar_state:get(State, shell, []),
debug_get_value(apps, ShellOpts, no_value,
"Found shell opts from command line option.").
-spec find_apps_relx(rebar_state:t()) -> no_value | list().
find_apps_relx(State) ->
{Opts, _} = rebar_state:command_parsed_args(State),
RelxOpts = rebar_state:get(State, relx, []),
{Defname, Defvsn} = debug_get_value(default_release, RelxOpts,
{undefined, undefined},
"Found default release from config"),
Relname = debug_get_value(relname, Opts, Defname,
"Found relname from command line option"),
Relvsn = debug_get_value(relvsn, Opts, Defvsn,
"Found relvsn from command line option"),
Releases = [Rel || Rel <- rebar_state:get(State, relx, []),
is_tuple(Rel), element(1, Rel) =:= release,
tuple_size(Rel) =:= 3 orelse tuple_size(Rel) =:= 4,
{Name, Vsn} <- [element(2, Rel)],
Relname == undefined orelse Name == Relname,
Relvsn == undefined orelse Vsn == Relvsn],
case Releases of
[] ->
no_value;
[{_, _, Apps}|_] ->
?DEBUG("Found shell apps from relx.", []),
Apps;
[{_, _, Apps, _}|_] ->
?DEBUG("Found shell apps from relx.", []),
Apps
end.
load_apps(Apps) ->
[case application:load(App) of
ok ->
{ok, Ks} = application:get_all_key(App),
load_apps(proplists:get_value(applications, Ks));
_ ->
error % will be caught when starting the app
end || App <- normalize_load_apps(Apps),
not lists:keymember(App, 1, application:loaded_applications())],
ok.
reread_config(AppsToStart, State) ->
case find_config(State) of
no_config ->
ok;
ConfigList ->
%% This allows people who use applications that are also
%% depended on by rebar3 or its plugins to change their
%% configuration at runtime based on the configuration files.
%%
%% To do this, we stop apps that are already started before
%% reloading their configuration.
%%
%% We make an exception for apps that:
%% - are not already running
%% - would not be restarted (and hence would break some
%% compatibility with rebar3)
%% - are not in the config files and would see no config
%% changes
%% - are not in a blacklist, where changing their config
%% would be risky to the shell or the rebar3 agent
%% functionality (i.e. changing inets may break proxy
%% settings, stopping `kernel' would break everything)
Running = [App || {App, _, _} <- application:which_applications()],
BlackList = [inets, stdlib, kernel, rebar],
_ = [application:stop(App)
|| Config <- ConfigList,
{App, _} <- Config,
lists:member(App, Running),
lists:member(App, AppsToStart),
not lists:member(App, BlackList)],
_ = rebar_utils:reread_config(ConfigList, [update_logger]),
ok
end.
boot_apps(Apps) ->
?WARN("The rebar3 shell is a development tool; to deploy "
"applications in production, consider using releases "
"(http://www.rebar3.org/docs/releases)", []),
Normalized = normalize_boot_apps(Apps),
Res = [application:ensure_all_started(App) || App <- Normalized],
_ = [?INFO("Booted ~p", [App])
|| {ok, Booted} <- Res,
App <- Booted],
_ = [?ERROR("Failed to boot ~p for reason ~p", [App, Reason])
|| {error, {App, Reason}} <- Res],
ok.
normalize_load_apps([]) -> [];
normalize_load_apps([{_App, none} | T]) -> normalize_load_apps(T);
normalize_load_apps([{App, _} | T]) -> [App | normalize_load_apps(T)];
normalize_load_apps([{App, _Vsn, load} | T]) -> [App | normalize_load_apps(T)];
normalize_load_apps([{_App, _Vsn, none} | T]) -> normalize_load_apps(T);
normalize_load_apps([{App, _Vsn, Operator} | T]) when is_atom(Operator) ->
[App | normalize_load_apps(T)];
normalize_load_apps([App | T]) when is_atom(App) -> [App | normalize_load_apps(T)].
normalize_boot_apps([]) -> [];
normalize_boot_apps([{_App, load} | T]) -> normalize_boot_apps(T);
normalize_boot_apps([{_App, _Vsn, load} | T]) -> normalize_boot_apps(T);
normalize_boot_apps([{_App, none} | T]) -> normalize_boot_apps(T);
normalize_boot_apps([{_App, _Vsn, none} | T]) -> normalize_boot_apps(T);
normalize_boot_apps([{App, _Vsn, Operator} | T]) when is_atom(Operator) ->
[App | normalize_boot_apps(T)];
normalize_boot_apps([{App, _Vsn} | T]) -> [App | normalize_boot_apps(T)];
normalize_boot_apps([App | T]) when is_atom(App) -> [App | normalize_boot_apps(T)].
remove_error_handler(0) ->
?WARN("Unable to remove simple error_logger handler", []);
remove_error_handler(N) ->
case gen_event:delete_handler(error_logger, error_logger, []) of
{error, module_not_found} -> ok;
{error_logger, _} -> remove_error_handler(N-1)
end.
%% Timeout is a period to wait before giving up
wait_until_user_started(0) ->
?ABORT("Timeout exceeded waiting for `user` to register itself", []),
erlang:error(timeout);
wait_until_user_started(Timeout) ->
case whereis(user) of
%% if user is not yet registered wait a tenth of a second and try again
undefined -> timer:sleep(100), wait_until_user_started(Timeout - 100);
_ -> ok
end.
add_test_paths(State) ->
_ = [begin
AppDir = rebar_app_info:out_dir(App),
%% ignore errors resulting from non-existent directories
_ = code:add_path(filename:join([AppDir, "test"]))
end || App <- rebar_state:project_apps(State)],
_ = code:add_path(filename:join([rebar_dir:base_dir(State), "test"])),
ok.
% First try the --config flag, then try the relx sys_config
-spec find_config(rebar_state:t()) -> [[tuple()]] | no_config.
find_config(State) ->
case first_value([fun find_config_option/1,
fun find_config_rebar/1,
fun find_config_relx/1], State) of
no_value ->
no_config;
Filename when is_list(Filename) ->
case is_src_config(Filename) of
false ->
rebar_file_utils:consult_config(State, Filename);
true ->
consult_env_config(State, Filename)
end
end.
-spec first_value([Fun], State) -> no_value | Value when
Value :: any(),
State :: rebar_state:t(),
Fun :: fun ((State) -> no_value | Value).
first_value([], _) -> no_value;
first_value([Fun | Rest], State) ->
case Fun(State) of
no_value ->
first_value(Rest, State);
Value ->
Value
end.
debug_get_value(Key, List, Default, Description) ->
case proplists:get_value(Key, List, Default) of
Default -> Default;
Value ->
?DEBUG(Description, []),
Value
end.
-spec find_config_option(rebar_state:t()) -> Filename::list() | no_value.
find_config_option(State) ->
{Opts, _} = rebar_state:command_parsed_args(State),
debug_get_value(config, Opts, no_value,
"Found config from command line option.").
-spec find_config_rebar(rebar_state:t()) -> [tuple()] | no_value.
find_config_rebar(State) ->
debug_get_value(config, rebar_state:get(State, shell, []), no_value,
"Found config from rebar config file.").
-spec find_config_relx(rebar_state:t()) -> [tuple()] | no_value.
find_config_relx(State) ->
%% The order in relx is to load the src version first;
%% we do the same.
RelxCfg = rebar_state:get(State, relx, []),
Src = debug_get_value(sys_config_src, RelxCfg, no_value,
"Found config.src from relx."),
case Src of
no_value ->
debug_get_value(sys_config, RelxCfg, no_value,
"Found config from relx.");
_ ->
Src
end.
-spec is_src_config(file:filename()) -> boolean().
is_src_config(Filename) ->
filename:extension(Filename) =:= ".src".
-spec consult_env_config(rebar_state:t(), file:filename()) -> [[tuple()]].
consult_env_config(State, Filename) ->
RawString = case file:read_file(Filename) of
{error, _} -> "[].";
{ok, Bin} -> unicode:characters_to_list(Bin)
end,
ReplacedStr = replace_env_vars(RawString),
case rebar_string:consult(unicode:characters_to_list(ReplacedStr)) of
{error, Reason} ->
throw(?PRV_ERROR({bad_term_file, Filename, Reason}));
[Terms] ->
rebar_file_utils:consult_config_terms(State, Terms)
end.
maybe_set_env_vars(State) ->
EnvFile =debug_get_value(env_file, rebar_state:get(State, shell, []), undefined,
"Found env_file from config."),
{Opts, _} = rebar_state:command_parsed_args(State),
EnvFile1 = debug_get_value(env_file, Opts, EnvFile,
"Found env_file from command line option."),
case maybe_read_file(EnvFile1) of
ignore ->
ok;
{error, _} ->
?WARN("Failed to read file with environment variables: ~p", [EnvFile1]);
{ok, Bin} ->
Lines = string:split(unicode:characters_to_list(Bin), "\n", all),
[handle_env_var_line(Line) || Line <- Lines]
end.
handle_env_var_line(Line) ->
Trimmed = rebar_string:trim(Line, both, [$\s]),
%% ignore lines starting with # and
%% fail if there are spaces around =
case re:run(Trimmed, "^(?<key>[^#][^\s=]*)=(?<value>[^\s]\.*)",
[{capture, [key, value], list}, unicode]) of
{match, [Key, Value]} ->
os:putenv(Key, Value);
_ ->
case Trimmed of
[$# | _] -> ignore;
[] -> ignore;
Other ->
?WARN("Unable to parse environment variable from this line: ~ts", [Other])
end
end.
maybe_read_file(undefined) ->
ignore;
maybe_read_file(EnvFile) ->
file:read_file(EnvFile).
%% @doc quick and simple variable substitution writeup.
%% Supports `${varname}' but not `$varname' nor nested
%% values such as `${my_${varname}}'.
%% The variable are also defined as only supporting
%% the form `[a-zA-Z_]+[a-zA-Z0-9_]*' as per the POSIX
%% standard.
-spec replace_env_vars(string()) -> unicode:charlist().
replace_env_vars("") -> "";
replace_env_vars("${" ++ Str) ->
case until_var_end(Str) of
{ok, VarName, Rest} ->
replace_varname(VarName) ++ replace_env_vars(Rest);
error ->
"${" ++ replace_env_vars(Str)
end;
replace_env_vars([Char|Str]) ->
[Char | replace_env_vars(Str)].
until_var_end(Str) ->
case re:run(Str, "([a-zA-Z_]+[a-zA-Z0-9_]*)}", [{capture, [1], list}]) of
nomatch ->
error;
{match, [Name]} ->
{ok, Name, drop_varname(Name, Str)}
end.
replace_varname(Var) ->
%% os:getenv(Var, "") is only available in OTP-18.0
case os:getenv(Var) of
false -> "";
Val -> Val
end.
drop_varname("", "}" ++ Str) -> Str;
drop_varname([_|Var], [_|Str]) -> drop_varname(Var, Str).