%%%-------------------------------------------------------------------
%%% @author Niclas Axelsson <niclas@burbas.se>
%%% @doc
%%%
%%% @end
%%%-------------------------------------------------------------------
-module(nova_router).
-behaviour(cowboy_middleware).
%% Cowboy middleware-callbacks
-export([
execute/2
]).
%% API
-export([
compile/1,
lookup_url/1,
lookup_url/2,
lookup_url/3,
render_status_page/2,
render_status_page/3,
render_status_page/5,
%% Expose the router-callback
routes/1
]).
-include_lib("kernel/include/logger.hrl").
-include_lib("routing_tree/include/routing_tree.hrl").
-include("nova_router.hrl").
-type bindings() :: #{binary() := binary()}.
-export_type([bindings/0]).
%% This module is also exposing callbacks for routers
-callback routes(Env :: atom()) -> {ok, Routes :: any()}.
-spec compile(Apps :: [atom()]) -> host_tree().
compile(Apps) ->
UseStrict = application:get_env(nova, use_strict_routing, false),
Dispatch = compile(Apps, routing_tree:new(#{use_strict => UseStrict, convert_to_binary => true}), #{}),
persistent_put(nova_dispatch, Dispatch),
Dispatch.
-spec execute(Req, Env :: cowboy_middleware:env()) -> {ok, Req, Env0} | {stop, Req}
when Req::cowboy_req:req(),
Env0::cowboy_middleware:env().
execute(Req = #{host := Host, path := Path, method := Method}, Env) ->
Dispatch = persistent_get(nova_dispatch, Env),
case routing_tree:lookup(Host, Path, Method, Dispatch) of
{error, not_found} -> render_status_page('_', 404, #{error => "Not found in path"}, Req, Env);
{ok, Bindings, #nova_handler_value{app = App, module = Module, function = Function,
secure = Secure, plugins = Plugins, extra_state = ExtraState}} ->
{ok,
Req#{plugins => Plugins,
bindings => Bindings},
Env#{app => App,
module => Module,
function => Function,
secure => Secure,
controller_data => #{},
extra_state => ExtraState
}
};
{ok, Bindings, #cowboy_handler_value{app = App, handler = Handler, arguments = Args,
plugins = Plugins, secure = Secure}} ->
{ok,
Req#{plugins => Plugins,
bindings => Bindings},
Env#{app => App,
cowboy_handler => Handler,
arguments => Args,
secure => Secure
}
};
{ok, Bindings, #cowboy_handler_value{app = App, handler = Handler, arguments = Args,
plugins = Plugins, secure = Secure}, PathInfo} ->
{ok,
Req#{path_info => PathInfo,
plugins => Plugins,
bindings => Bindings},
Env#{app => App,
cowboy_handler => Handler,
arguments => Args,
secure => Secure
}
};
Error ->
logger:error(#{"reason" => "Unexpected return from routing_tree:lookup/4", "return_object" => Error}),
render_status_page(Host, 404, #{error => Error}, Req, Env)
end.
lookup_url(Path) ->
lookup_url('_', Path).
lookup_url(Host, Path) ->
lookup_url(Host, Path, '_').
lookup_url(Host, Path, Method) ->
Dispatch = persistent_get(nova_dispatch),
lookup_url(Host, Path, Method, Dispatch).
lookup_url(Host, Path, Method, Dispatch) ->
routing_tree:lookup(Host, Path, Method, Dispatch).
%%%%%%%%%%%%%%%%%%%%%%%%
%% INTERNAL FUNCTIONS %%
%%%%%%%%%%%%%%%%%%%%%%%%
-spec compile(Apps :: [atom()], Dispatch :: host_tree(), Options :: map()) -> host_tree().
compile([], Dispatch, _Options) -> Dispatch;
compile([App|Tl], Dispatch, Options) ->
%% Fetch the router-module for this application
Router = erlang:list_to_atom(erlang:atom_to_list(App) ++ "_router"),
Env = nova:get_environment(),
%% Ensure that the module is loaded
Routes = erlang:apply(Router, routes, [Env]),
Options1 = Options#{app => App},
{ok, Dispatch1, Options2} = compile_paths(Routes, Dispatch, Options1),
compile(Tl, Dispatch1, Options2).
compile_paths([], Dispatch, Options) -> {ok, Dispatch, Options};
compile_paths([RouteInfo|Tl], Dispatch, Options) ->
App = maps:get(app, Options),
%% Fetch the global plugins
GlobalPlugins = application:get_env(nova, plugins, []),
Plugins = maps:get(plugins, RouteInfo, GlobalPlugins),
Value = #nova_handler_value{secure = maps:get(secure, Options, maps:get(security, RouteInfo, false)),
app = App, plugins = normalize_plugins(Plugins),
extra_state = maps:get(extra_state, RouteInfo, #{})},
Prefix = maps:get(prefix, Options, "") ++ maps:get(prefix, RouteInfo, ""),
Host = maps:get(host, RouteInfo, '_'),
SubApps = maps:get(apps, RouteInfo, []),
%% We need to add this app info to nova-env
NovaEnv = nova:get_env(apps, []),
NovaEnv0 = [{App, #{prefix => Prefix}} | NovaEnv],
nova:set_env(apps, NovaEnv0),
{ok, Dispatch1} = parse_url(Host, maps:get(routes, RouteInfo, []), Prefix, Value, Dispatch),
Dispatch2 = compile(SubApps, Dispatch1, Options#{value => Value, prefix => Prefix}),
compile_paths(Tl, Dispatch2, Options).
parse_url(_Host, [], _Prefix, _Value, Tree) -> {ok, Tree};
parse_url(Host, [{StatusCode, StaticFile}|Tl], Prefix, Value, Tree) when is_integer(StatusCode),
is_list(StaticFile) ->
%% We need to signal that we have a static file here somewhere
Value0 = Value#nova_handler_value{
module = nova_static,
function = execute},
%% TODO! Fix status-code so it's being threated specially
Tree0 = insert(Host, StatusCode, '_', Value0, Tree),
parse_url(Host, Tl, Prefix, Value0, Tree0);
parse_url(Host, [{StatusCode, {Module, Function}, Options}|Tl], Prefix, Value, Tree) when is_integer(StatusCode) ->
Value0 = Value#nova_handler_value{
module = Module,
function = Function},
Res = lists:foldl(fun(Method, Tree0) ->
insert(Host, StatusCode, Method, Value0, Tree0)
end, Tree, maps:get(methods, Options, ['_'])),
parse_url(Host, Tl, Prefix, Value, Res);
parse_url(Host,
[{RemotePath, LocalPath}|Tl],
Prefix, Value = #nova_handler_value{app = App, secure = Secure},
Tree) when is_list(RemotePath), is_list(LocalPath) ->
%% Static assets - check that the path exists
PrivPath = filename:join(code:lib_dir(App, priv), LocalPath),
Payload =
case {filelib:is_dir(LocalPath), filelib:is_dir(PrivPath)} of
{false, false} ->
%% No directory - check if it's a file
case {filelib:is_file(LocalPath), filelib:is_file(PrivPath)} of
{false, false} ->
%% No dir nor file
logger:warning(#{"reason" => "Could not find local path for the given resource",
"local_path" => LocalPath, "remote_path" => RemotePath}),
not_found;
{true, false} ->
{file, LocalPath};
{_, true} ->
{priv_file, App, LocalPath}
end;
{true, false} ->
{dir, LocalPath};
{_, true} ->
{priv_dir, App, LocalPath}
end,
Value0 = #cowboy_handler_value{
app = App,
handler = cowboy_static,
arguments = Payload,
plugins = Value#nova_handler_value.plugins,
secure = Secure
},
Tree0 = insert(Host, string:concat(Prefix, RemotePath), '_', Value0, Tree),
parse_url(Host, Tl, Prefix, Value, Tree0);
parse_url(Host,
[{RemotePath, LocalPath}|Tl],
Prefix,
Value = #nova_handler_value{app = App, secure = Secure}, Tree)
when is_list(RemotePath), is_list(LocalPath) ->
%% Static assets - check that the path exists
PrivPath = filename:join(code:lib_dir(App, priv), LocalPath),
Payload =
case {filelib:is_dir(LocalPath), filelib:is_dir(PrivPath)} of
{false, false} ->
%% No directory - check if it's a file
case {filelib:is_file(LocalPath), filelib:is_file(PrivPath)} of
{false, false} ->
%% No dir nor file
logger:warning(#{"reason" => "Could not find local path for the given resource",
"local_path" => LocalPath, "remote_path" => RemotePath}),
not_found;
{true, false} ->
{file, LocalPath};
{_, true} ->
{priv_file, App, LocalPath}
end;
{true, false} ->
{dir, LocalPath};
{_, true} ->
{priv_dir, App, LocalPath}
end,
Value0 = #cowboy_handler_value{
app = App,
handler = cowboy_static,
arguments = Payload,
plugins = Value#nova_handler_value.plugins,
secure = Secure
},
logger:debug(#{"action" => "Adding route", "route" => string:concat(Prefix, RemotePath), "app" => App}),
Tree0 = insert(Host, string:concat(Prefix, RemotePath), '_', Value0, Tree),
parse_url(Host, Tl, Prefix, Value, Tree0);
parse_url(Host,
[{Path, {Mod, Func}, Options}|Tl],
Prefix,
Value = #nova_handler_value{app = App, secure = _Secure},
Tree) ->
RealPath = case Path of
_ when is_list(Path) -> string:concat(Prefix, Path);
_ when is_integer(Path) -> Path;
_ -> throw({unknown_path, Path})
end,
Methods = maps:get(methods, Options, ['_']),
CompiledPaths =
lists:foldl(
fun(Method, Tree0) ->
BinMethod = method_to_binary(Method),
Value0 =
case maps:get(protocol, Options, http) of
http ->
Value#nova_handler_value{
module = Mod,
function = Func
}
end,
logger:debug(#{"action" => "Adding route", "route" => RealPath, "app" => App}),
insert(Host, RealPath, BinMethod, Value0, Tree0)
end, Tree, Methods),
parse_url(Host, Tl, Prefix, Value, CompiledPaths);
parse_url(Host,
[{Path, Mod, #{protocol := ws}} | Tl],
Prefix, #nova_handler_value{app = App, secure = Secure} = Value,
Tree) ->
Value0 = #cowboy_handler_value{
app = App,
handler = nova_ws_handler,
arguments = #{module => Mod},
plugins = Value#nova_handler_value.plugins,
secure = Secure},
logger:debug(#{"action" => "Adding route", "protocol" => "ws", "route" => Path, "app" => App}),
RealPath = string:concat(Prefix, Path),
CompiledPaths = insert(Host, RealPath, '_', Value0, Tree),
parse_url(Host, Tl, Prefix, Value, CompiledPaths);
parse_url(Host, [{Path, {Mod, Func}}|Tl], Prefix, Value, Tree) ->
parse_url(Host, [{Path, {Mod, Func}, #{}}|Tl], Prefix, Value, Tree).
-spec render_status_page(StatusCode :: integer(), Req :: cowboy_req:req()) ->
{ok, Req0 :: cowboy_req:req(), Env :: map()}.
render_status_page(StatusCode, Req) ->
render_status_page(StatusCode, #{}, Req).
-spec render_status_page(StatusCode :: integer(), Data :: map(), Req :: cowboy_req:req()) ->
{ok, Req0 :: cowboy_req:req(), Env :: map()}.
render_status_page(StatusCode, Data, Req) ->
Dispatch = persistent_get(nova_dispatch),
render_status_page('_', StatusCode, Data, Req, #{dispatch => Dispatch}).
-spec render_status_page(Host :: binary() | atom(),
StatusCode :: integer(),
Data :: map(),
Req :: cowboy_req:req(),
Env :: map()) -> {ok, Req0 :: cowboy_req:req(), Env :: map()}.
render_status_page(Host, StatusCode, Data, Req, Env) ->
Dispatch = persistent_get(nova_dispatch, Env),
Env0 =
case routing_tree:lookup(Host, StatusCode, '_', Dispatch) of
{error, _} ->
%% Render nova page if exists - We need to determine where to find this path?
Env#{app => nova,
module => nova_error_controller,
function => status_code,
secure => false,
controller_data => #{status => StatusCode, data => Data}};
{ok, Bindings, #nova_handler_value{app = App,
module = Module,
function = Function,
secure = Secure,
extra_state = ExtraState}} ->
Env#{app => App,
module => Module,
function => Function,
secure => Secure,
controller_data => #{status => StatusCode, data => Data},
bindings => Bindings,
extra_state => ExtraState}
end,
{ok, Req#{resp_status_code => StatusCode}, Env0}.
insert(Host, Path, Combinator, Value, Tree) ->
try routing_tree:insert(Host, Path, Combinator, Value, Tree) of
Tree0 -> Tree0
catch
throw:Exception ->
logger:error(#{"reason" => "Error when inserting route", "route" => Path, "combinator" => Combinator}),
throw(Exception);
Type:Exception ->
logger:error(#{"reason" => "Unexpected exit", "type" => Type, "exception" => Exception}),
throw(Exception)
end.
normalize_plugins(Plugins) ->
lists:reverse(normalize_plugins(Plugins, [])).
normalize_plugins([], Ack) -> Ack;
normalize_plugins([{Type, PluginName, Options}|Tl], Ack) ->
ExistingPlugins = proplists:get_value(Type, Ack, []),
normalize_plugins(Tl, [{Type, [{PluginName, Options}|ExistingPlugins]}|proplists:delete(Type, Ack)]).
method_to_binary(get) -> <<"GET">>;
method_to_binary(post) -> <<"POST">>;
method_to_binary(put) -> <<"PUT">>;
method_to_binary(delete) -> <<"DELETE">>;
method_to_binary(options) -> <<"OPTIONS">>;
method_to_binary(head) -> <<"HEAD">>;
method_to_binary(connect) -> <<"CONNECT">>;
method_to_binary(trace) -> <<"TRACE">>;
method_to_binary(patch) -> <<"PATCH">>;
method_to_binary(_) -> '_'.
persistent_put(Key, Value) ->
case application:get_env(nova, use_persistent_term, true) of
true ->
persistent_term:put(Key, Value);
_ ->
ok
end.
persistent_get(Key) ->
case application:get_env(nova, use_persistent_term, true) of
true ->
persistent_term:get(Key);
_ ->
logger:warning(#{"reason" => "Called persistent_get/1 without option use_persistent_term set to true"}),
throw({unsupported_operation, persistent_get})
end.
persistent_get(Key, Env) ->
case application:get_env(nova, use_persistent_term, true) of
true ->
persistent_term:get(Key);
_ ->
maps:get(Key, Env)
end.
routes(_) ->
[#{
routes => [
{404, { nova_error_controller, not_found }, #{}},
{500, { nova_error_controller, server_error }, #{}}
]
}].
-ifdef(TEST).
-compile(export_all). %% Export all functions for testing purpose
-include_lib("eunit/include/eunit.hrl").
-endif.
