mirror of
https://github.com/NixOS/nixpkgs.git
synced 2024-11-27 16:11:58 +00:00
113 lines
4.1 KiB
Erlang
Executable file
113 lines
4.1 KiB
Erlang
Executable file
#!/usr/bin/env escript
|
|
%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
|
|
%%! -smp enable
|
|
%%% ---------------------------------------------------------------------------
|
|
%%% @doc
|
|
%%% The purpose of this command is to prepare a rebar3 project so that
|
|
%%% rebar3 understands that the dependencies are all already
|
|
%%% installed. If you want a hygienic build on nix then you must run
|
|
%%% this command before running rebar3. I suggest that you add a
|
|
%%% `Makefile` to your project and have the bootstrap command be a
|
|
%%% dependency of the build commands. See the nix documentation for
|
|
%%% more information.
|
|
%%%
|
|
%%% This command designed to have as few dependencies as possible so
|
|
%%% that it can be a dependency of root level packages like rebar3. To
|
|
%%% that end it does many things in a fairly simplistic way. That is
|
|
%%% by design.
|
|
%%%
|
|
%%% ### Assumptions
|
|
%%%
|
|
%%% This command makes the following assumptions:
|
|
%%%
|
|
%%% * It is run in a nix-shell or nix-build environment
|
|
%%% * that all dependencies have been added to the ERL_LIBS
|
|
%%% Environment Variable
|
|
|
|
-record(data, {version
|
|
, erl_libs
|
|
, root
|
|
, name
|
|
, registry_snapshot}).
|
|
-define(LOCAL_HEX_REGISTRY, "registry.ets").
|
|
|
|
main(Args) ->
|
|
{ok, RequiredData} = gather_required_data_from_the_environment(Args),
|
|
ok = bootstrap_libs(RequiredData).
|
|
|
|
%% @doc
|
|
%% This takes an app name in the standard OTP <name>-<version> format
|
|
%% and returns just the app name. Why? because rebar is doesn't
|
|
%% respect OTP conventions in some cases.
|
|
-spec fixup_app_name(file:name()) -> string().
|
|
fixup_app_name(Path) ->
|
|
BaseName = filename:basename(Path),
|
|
case string:tokens(BaseName, "-") of
|
|
[Name, _Version] -> Name;
|
|
Name -> Name
|
|
end.
|
|
|
|
|
|
-spec gather_required_data_from_the_environment([string()]) -> {ok, #data{}}.
|
|
gather_required_data_from_the_environment(_) ->
|
|
{ok, #data{ version = guard_env("version")
|
|
, erl_libs = os:getenv("ERL_LIBS", [])
|
|
, root = code:root_dir()
|
|
, name = guard_env("name")
|
|
, registry_snapshot = guard_env("HEX_REGISTRY_SNAPSHOT")}}.
|
|
|
|
-spec guard_env(string()) -> string().
|
|
guard_env(Name) ->
|
|
case os:getenv(Name) of
|
|
false ->
|
|
stderr("Expected Environment variable ~s! Are you sure you are "
|
|
"running in a Nix environment? Either a nix-build, "
|
|
"nix-shell, etc?~n", [Name]),
|
|
erlang:halt(1);
|
|
Variable ->
|
|
Variable
|
|
end.
|
|
|
|
-spec bootstrap_libs(#data{}) -> ok.
|
|
bootstrap_libs(#data{erl_libs = ErlLibs}) ->
|
|
io:format("Bootstrapping dependent libraries~n"),
|
|
Target = "_build/prod/lib/",
|
|
Paths = string:tokens(ErlLibs, ":"),
|
|
CopiableFiles =
|
|
lists:foldl(fun(Path, Acc) ->
|
|
gather_directory_contents(Path) ++ Acc
|
|
end, [], Paths),
|
|
lists:foreach(fun (Path) ->
|
|
ok = link_app(Path, Target)
|
|
end, CopiableFiles).
|
|
|
|
-spec gather_directory_contents(string()) -> [{string(), string()}].
|
|
gather_directory_contents(Path) ->
|
|
{ok, Names} = file:list_dir(Path),
|
|
lists:map(fun(AppName) ->
|
|
{filename:join(Path, AppName), fixup_app_name(AppName)}
|
|
end, Names).
|
|
|
|
%% @doc
|
|
%% Makes a symlink from the directory pointed at by Path to a
|
|
%% directory of the same name in Target. So if we had a Path of
|
|
%% {`foo/bar/baz/bash`, `baz`} and a Target of `faz/foo/foos`, the symlink
|
|
%% would be `faz/foo/foos/baz`.
|
|
-spec link_app({string(), string()}, string()) -> ok.
|
|
link_app({Path, TargetFile}, TargetDir) ->
|
|
Target = filename:join(TargetDir, TargetFile),
|
|
ok = make_symlink(Path, Target).
|
|
|
|
-spec make_symlink(string(), string()) -> ok.
|
|
make_symlink(Path, TargetFile) ->
|
|
file:delete(TargetFile),
|
|
ok = filelib:ensure_dir(TargetFile),
|
|
io:format("Making symlink from ~s to ~s~n", [Path, TargetFile]),
|
|
ok = file:make_symlink(Path, TargetFile).
|
|
|
|
%% @doc
|
|
%% Write the result of the format string out to stderr.
|
|
-spec stderr(string(), [term()]) -> ok.
|
|
stderr(FormatStr, Args) ->
|
|
io:put_chars(standard_error, io_lib:format(FormatStr, Args)).
|