diff options
author | Adam Kocoloski <adam@cloudant.com> | 2010-08-11 15:52:06 -0400 |
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committer | Adam Kocoloski <adam@cloudant.com> | 2010-08-11 17:39:38 -0400 |
commit | 498d5c85681ddfea577377b8e10051fb445ac0c2 (patch) | |
tree | 10c4d32773d703374d000f7dc0ae3988f6926366 /apps/mochiweb/src/reloader.erl | |
parent | 7e67565d2241783b5f24a37400ddae83b00c7a81 (diff) |
move mochiweb to rebar layout
Diffstat (limited to 'apps/mochiweb/src/reloader.erl')
-rw-r--r-- | apps/mochiweb/src/reloader.erl | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/apps/mochiweb/src/reloader.erl b/apps/mochiweb/src/reloader.erl new file mode 100644 index 00000000..6835f8f9 --- /dev/null +++ b/apps/mochiweb/src/reloader.erl @@ -0,0 +1,123 @@ +%% @copyright 2007 Mochi Media, Inc. +%% @author Matthew Dempsky <matthew@mochimedia.com> +%% +%% @doc Erlang module for automatically reloading modified modules +%% during development. + +-module(reloader). +-author("Matthew Dempsky <matthew@mochimedia.com>"). + +-include_lib("kernel/include/file.hrl"). + +-behaviour(gen_server). +-export([start/0, start_link/0]). +-export([stop/0]). +-export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2, code_change/3]). + +-record(state, {last, tref}). + +%% External API + +%% @spec start() -> ServerRet +%% @doc Start the reloader. +start() -> + gen_server:start({local, ?MODULE}, ?MODULE, [], []). + +%% @spec start_link() -> ServerRet +%% @doc Start the reloader. +start_link() -> + gen_server:start_link({local, ?MODULE}, ?MODULE, [], []). + +%% @spec stop() -> ok +%% @doc Stop the reloader. +stop() -> + gen_server:call(?MODULE, stop). + +%% gen_server callbacks + +%% @spec init([]) -> {ok, State} +%% @doc gen_server init, opens the server in an initial state. +init([]) -> + {ok, TRef} = timer:send_interval(timer:seconds(1), doit), + {ok, #state{last = stamp(), tref = TRef}}. + +%% @spec handle_call(Args, From, State) -> tuple() +%% @doc gen_server callback. +handle_call(stop, _From, State) -> + {stop, shutdown, stopped, State}; +handle_call(_Req, _From, State) -> + {reply, {error, badrequest}, State}. + +%% @spec handle_cast(Cast, State) -> tuple() +%% @doc gen_server callback. +handle_cast(_Req, State) -> + {noreply, State}. + +%% @spec handle_info(Info, State) -> tuple() +%% @doc gen_server callback. +handle_info(doit, State) -> + Now = stamp(), + doit(State#state.last, Now), + {noreply, State#state{last = Now}}; +handle_info(_Info, State) -> + {noreply, State}. + +%% @spec terminate(Reason, State) -> ok +%% @doc gen_server termination callback. +terminate(_Reason, State) -> + {ok, cancel} = timer:cancel(State#state.tref), + ok. + + +%% @spec code_change(_OldVsn, State, _Extra) -> State +%% @doc gen_server code_change callback (trivial). +code_change(_Vsn, State, _Extra) -> + {ok, State}. + +%% Internal API + +doit(From, To) -> + [case file:read_file_info(Filename) of + {ok, #file_info{mtime = Mtime}} when Mtime >= From, Mtime < To -> + reload(Module); + {ok, _} -> + unmodified; + {error, enoent} -> + %% The Erlang compiler deletes existing .beam files if + %% recompiling fails. Maybe it's worth spitting out a + %% warning here, but I'd want to limit it to just once. + gone; + {error, Reason} -> + io:format("Error reading ~s's file info: ~p~n", + [Filename, Reason]), + error + end || {Module, Filename} <- code:all_loaded(), is_list(Filename)]. + +reload(Module) -> + io:format("Reloading ~p ...", [Module]), + code:purge(Module), + case code:load_file(Module) of + {module, Module} -> + io:format(" ok.~n"), + case erlang:function_exported(Module, test, 0) of + true -> + io:format(" - Calling ~p:test() ...", [Module]), + case catch Module:test() of + ok -> + io:format(" ok.~n"), + reload; + Reason -> + io:format(" fail: ~p.~n", [Reason]), + reload_but_test_failed + end; + false -> + reload + end; + {error, Reason} -> + io:format(" fail: ~p.~n", [Reason]), + error + end. + + +stamp() -> + erlang:localtime(). |