feat: read the dispatch table through nova_routing_trie

rebar.config

@@ -58,8 +58,7 @@
 {dialyzer, [
     {plt_apps, all_deps},
     {plt_extra_apps, [
-        nova,
-        routing_tree
+        nova
     ]},
     {warnings, [no_unknown]}
 ]}.

src/rebar3_nova.app.src

@@ -6,7 +6,6 @@
         kernel,
         stdlib,
         nova,
-        routing_tree,
         fs
     ]},
     {env, []},

src/rebar3_nova_audit.erl

@@ -2,8 +2,10 @@
 
 -export([init/1, do/1, format_error/1]).
 
+%% Exported for rebar3_nova_dispatch_SUITE.
+-export([collect_routes/1]).
+
 -include("nova_router.hrl").
--include_lib("routing_tree/include/routing_tree.hrl").
 
 -define(PROVIDER, audit).
 -define(DEPS, [{default, compile}]).
@@ -106,74 +108,30 @@ is_mutation(<<"delete">>) -> true;
 is_mutation(<<"patch">>) -> true;
 is_mutation(_) -> false.
 
-collect_routes(#host_tree{hosts = Hosts}) ->
-    lists:flatmap(
-        fun({_Host, #routing_tree{tree = Tree}}) ->
-            collect_nodes(Tree, <<>>)
-        end,
-        Hosts
-    ).
+collect_routes(Dispatch) ->
+    lists:flatmap(fun classify_route/1, rebar3_nova_dispatch:routes(Dispatch)).
 
-collect_nodes([], _Prefix) ->
+classify_route({_Path, _Method, #nova_handler_value{module = nova_file_controller}}) ->
     [];
-collect_nodes([#node{is_wildcard = true} | Tl], Prefix) ->
-    collect_nodes(Tl, Prefix);
-collect_nodes([#node{segment = Segment} | Tl], Prefix) when is_integer(Segment) ->
-    collect_nodes(Tl, Prefix);
-collect_nodes(
-    [#node{segment = Segment, is_binding = IsBinding, value = Value, children = Children} | Tl],
-    Prefix
-) ->
-    SegBin = segment_to_binary(Segment, IsBinding),
-    NewPrefix = <<Prefix/binary, "/", SegBin/binary>>,
-    HandlerRoutes = lists:filtermap(
-        fun(NodeComp) -> classify_handler(NodeComp, NewPrefix) end, Value
-    ),
-    lists:flatten(HandlerRoutes) ++ collect_nodes(Children, NewPrefix) ++ collect_nodes(Tl, Prefix).
-
-segment_to_binary(Segment, true) when is_binary(Segment) ->
-    <<"{", Segment/binary, "}">>;
-segment_to_binary(Segment, _) when is_binary(Segment) ->
-    Segment;
-segment_to_binary(Segment, IsBinding) when is_list(Segment) ->
-    segment_to_binary(erlang:list_to_binary(Segment), IsBinding).
-
-classify_handler(#node_comp{value = #nova_handler_value{module = nova_file_controller}}, _Path) ->
-    false;
-classify_handler(#node_comp{value = #nova_handler_value{module = nova_error_controller}}, _Path) ->
-    false;
-classify_handler(
-    #node_comp{
-        comparator = Method,
-        value = #nova_handler_value{
-            module = undefined,
-            function = undefined,
-            callback = Callback,
-            secure = Secure
-        }
-    },
-    Path
+classify_route({_Path, _Method, #nova_handler_value{module = nova_error_controller}}) ->
+    [];
+classify_route(
+    {Path, Method, #nova_handler_value{
+        module = undefined,
+        function = undefined,
+        callback = Callback,
+        secure = Secure
+    }}
 ) ->
     {module, Module} = lists:keyfind(module, 1, erlang:fun_info(Callback)),
-    expand_methods(Method, Path, Module, Secure);
-classify_handler(
-    #node_comp{
-        comparator = Method,
-        value = #nova_handler_value{module = Module, secure = Secure}
-    },
-    Path
-) ->
-    expand_methods(Method, Path, Module, Secure);
-classify_handler(#node_comp{value = #cowboy_handler_value{}}, _Path) ->
-    false.
+    expand_methods(Method, rebar3_nova_dispatch:openapi_path(Path), Module, Secure);
+classify_route({Path, Method, #nova_handler_value{module = Module, secure = Secure}}) ->
+    expand_methods(Method, rebar3_nova_dispatch:openapi_path(Path), Module, Secure);
+classify_route({_Path, _Method, #cowboy_handler_value{}}) ->
+    [].
 
 expand_methods('_', Path, Module, Secure) ->
     Methods = [<<"get">>, <<"post">>, <<"put">>, <<"delete">>, <<"patch">>],
-    {true, [{Path, M, Secure, Module, true} || M <- Methods]};
+    [{Path, M, Secure, Module, true} || M <- Methods];
 expand_methods(Method, Path, Module, Secure) ->
-    {true, [{Path, method_to_binary(Method), Secure, Module, false}]}.
-
-method_to_binary(Method) when is_atom(Method) ->
-    erlang:atom_to_binary(Method);
-method_to_binary(Method) when is_binary(Method) ->
-    string:lowercase(Method).
+    [{Path, rebar3_nova_dispatch:method_to_binary(Method), Secure, Module, false}].

src/rebar3_nova_dispatch.erl

@@ -0,0 +1,66 @@
+%%%-------------------------------------------------------------------
+%%% @doc
+%%% Reads a compiled Nova dispatch table.
+%%%
+%%% The routing table used to be a `routing_tree' record that every task
+%%% walked for itself. It is now an opaque structure owned by
+%%% `nova_routing_trie', so this module is the single place that talks to its
+%%% introspection API and hands the tasks a flat list of routes.
+%%% @end
+%%%-------------------------------------------------------------------
+-module(rebar3_nova_dispatch).
+
+-export([
+    routes/1,
+    openapi_path/1,
+    method_to_binary/1
+]).
+
+-type route() :: {Path :: binary(), Method :: '_' | binary(), Payload :: term()}.
+-export_type([route/0]).
+
+%%--------------------------------------------------------------------
+%% @doc
+%% Every URL route in a compiled dispatch table.
+%%
+%% Status-code routes (Nova's error pages, which are keyed by integer rather
+%% than by path) are left out, since none of the tasks that call this report
+%% on them.
+%% @end
+%%--------------------------------------------------------------------
+-spec routes(Dispatch :: nova_routing_trie:trie()) -> [route()].
+routes(Dispatch) ->
+    [
+        {Path, Method, Payload}
+     || {_Host, Path, Method, Payload} <- nova_routing_trie:routes(Dispatch),
+        is_binary(Path)
+    ].
+
+%%--------------------------------------------------------------------
+%% @doc
+%% Rewrite a Nova path into the OpenAPI style, so `/users/:id' becomes
+%% `/users/{id}'. A trailing `[...]' catch-all has no OpenAPI equivalent and
+%% is dropped.
+%% @end
+%%--------------------------------------------------------------------
+-spec openapi_path(Path :: binary()) -> binary().
+openapi_path(Path) ->
+    Segments = [openapi_segment(S) || S <- binary:split(Path, <<"/">>, [global]), S =/= <<>>],
+    case [S || S <- Segments, S =/= skip] of
+        [] -> <<"/">>;
+        Kept -> <<<<"/", S/binary>> || S <- Kept>>
+    end.
+
+openapi_segment(<<":", Name/binary>>) -> <<"{", Name/binary, "}">>;
+openapi_segment(<<"[...]">>) -> skip;
+openapi_segment(Segment) -> Segment.
+
+%%--------------------------------------------------------------------
+%% @doc
+%% The lowercase name of an HTTP method, as the report formats want it.
+%% @end
+%%--------------------------------------------------------------------
+-spec method_to_binary(Method :: '_' | binary() | atom()) -> binary().
+method_to_binary('_') -> <<"any">>;
+method_to_binary(Method) when is_binary(Method) -> string:lowercase(Method);
+method_to_binary(Method) when is_atom(Method) -> string:lowercase(atom_to_binary(Method, utf8)).

src/rebar3_nova_doctor.erl

@@ -2,8 +2,10 @@
 
 -export([init/1, do/1, format_error/1]).
 
+%% Exported for rebar3_nova_dispatch_SUITE.
+-export([collect_route_handlers/1]).
+
 -include("nova_router.hrl").
--include_lib("routing_tree/include/routing_tree.hrl").
 
 -ifdef(TEST).
 -export([
@@ -236,65 +238,25 @@ check_routes(State) ->
             ]
     end.
 
-collect_route_handlers(#host_tree{hosts = Hosts}) ->
-    lists:flatmap(
-        fun({_Host, #routing_tree{tree = Tree}}) -> walk_tree(Tree, <<>>) end,
-        Hosts
-    ).
-
-walk_tree([], _Prefix) ->
-    [];
-walk_tree(
-    [#node{segment = Segment, is_binding = IsBinding, value = Value, children = Children} | Tl],
-    Prefix
-) ->
-    Seg = seg_bin(Segment, IsBinding),
-    NewPrefix = <<Prefix/binary, "/", Seg/binary>>,
-    [extract_handler(NC, NewPrefix) || NC <- Value] ++
-        walk_tree(Children, NewPrefix) ++
-        walk_tree(Tl, Prefix).
-
-seg_bin(S, true) when is_binary(S) -> <<"{", S/binary, "}">>;
-seg_bin(S, true) when is_list(S) -> <<"{", (list_to_binary(S))/binary, "}">>;
-seg_bin(S, _) when is_binary(S) -> S;
-seg_bin(S, _) when is_list(S) -> list_to_binary(S);
-seg_bin(S, _) when is_integer(S) -> integer_to_binary(S);
-seg_bin(_, _) -> <<"_">>.
+collect_route_handlers(Dispatch) ->
+    [extract_handler(Route) || Route <- rebar3_nova_dispatch:routes(Dispatch)].
 
 extract_handler(
-    #node_comp{
-        comparator = Method,
-        value = #nova_handler_value{
-            module = undefined,
-            function = undefined,
-            callback = Cb
-        }
-    },
-    Path
-) when
-    is_function(Cb)
-->
+    {Path, Method, #nova_handler_value{
+        module = undefined,
+        function = undefined,
+        callback = Cb
+    }}
+) when is_function(Cb) ->
     {module, M} = lists:keyfind(module, 1, erlang:fun_info(Cb)),
     {Path, Method, M, '$callback', captured};
-extract_handler(
-    #node_comp{
-        comparator = Method,
-        value = #nova_handler_value{module = Mod, function = Func}
-    },
-    Path
-) when
+extract_handler({Path, Method, #nova_handler_value{module = Mod, function = Func}}) when
     Mod =/= undefined
 ->
     {Path, Method, Mod, Func, 1};
-extract_handler(
-    #node_comp{
-        comparator = Method,
-        value = #cowboy_handler_value{handler = Handler}
-    },
-    Path
-) ->
+extract_handler({Path, Method, #cowboy_handler_value{handler = Handler}}) ->
     {Path, Method, Handler, init, 2};
-extract_handler(#node_comp{comparator = Method}, Path) ->
+extract_handler({Path, Method, _Payload}) ->
     {Path, Method, unknown, unknown, 1}.
 
 check_handler({_Path, _Method, unknown, _, _}) ->