HTTP controller API

.gitignore

@@ -16,3 +16,5 @@ ergw.config
 data.ergw*
 log.ergw*
 apps/ergw_core/priv*
+data
+ergw@*

apps/ergw/src/ergw_config.erl

@@ -13,7 +13,8 @@
 -compile({no_auto_import,[put/2]}).
 
 %% API
--export([load/0, apply/1, serialize_config/1]).
+-export([load/0, apply/1, serialize_config/1, load_part_of_config/1]).
+-export([ergw_core_init/2]).
 
 -ifdef(TEST).
 -export([config_meta/0,
@@ -45,6 +46,16 @@
 %%% API
 %%%===================================================================
 
+load_part_of_config(Config) when is_map(Config) ->
+    load_typespecs(),
+    do([error_m ||
+        load_schemas(),
+        validate_config_with_schema(Config),
+        return(coerce_config(Config))
+    ]);
+load_part_of_config(Config) ->
+    erlang:error(badarg, [Config]).
+
 load() ->
     load_typespecs(),
     do([error_m ||
@@ -129,8 +140,9 @@ ergw_aaa_init(apps, #{apps := Apps0}) ->
     Apps = ergw_aaa_config:validate_options(fun ergw_aaa_config:validate_app/2, Apps0, []),
     maps:map(fun ergw_aaa:add_application/2, Apps),
     Apps;
-ergw_aaa_init(_, _) ->
-    ok.
+ergw_aaa_init(K, _) ->
+    ?LOG(warning, "The key ~p is missed in config of erGW-AAA", [K]),
+    {error, unhandled}.
 
 ergw_sbi_client_init(Opts) ->
     ergw_sbi_client_config:validate_options(fun ergw_sbi_client_config:validate_option/2, Opts).
@@ -185,8 +197,9 @@ ergw_core_init(proxy_map, #{proxy_map := Map}) ->
     ok = ergw_core:setopts(proxy_map, Map);
 ergw_core_init(http_api, #{http_api := Opts}) ->
     ergw_http_api:init(Opts);
-ergw_core_init(_K, _) ->
-    ok.
+ergw_core_init(K, _) ->
+    ?LOG(warning, "The key ~p is missed in config of erGW", [K]),
+    {error, unhandled}.
 
 ergw_charging_init(rules, #{rules := Rules}) ->
     maps:map(fun ergw_core:add_charging_rule/2, Rules);

apps/ergw/src/ergw_http_api.erl

@@ -39,6 +39,8 @@ start_http_listener(#{enabled := true} = Opts) ->
 		    {"/status/[...]", http_status_handler, []},
 		    %% 5G SBI APIs
 		    {"/sbi/nbsf-management/v1/pcfBindings", sbi_nbsf_handler, []},
+		    %% HTTP controller
+		    {"/api/v1/controller", http_controller_handler, []},
 		    %% serves static files for swagger UI
 		    {"/api/v1/spec/ui", swagger_ui_handler, []},
 		    {"/api/v1/spec/ui/[...]", cowboy_static, {priv_dir, ergw_core, "static"}}]}

apps/ergw/src/http_controller_handler.erl

@@ -0,0 +1,163 @@
+%% Copyright 2021, Travelping GmbH <info@travelping.com>
+
+%% This program is free software; you can redistribute it and/or
+%% modify it under the terms of the GNU General Public License
+%% as published by the Free Software Foundation; either version
+%% 2 of the License, or (at your option) any later version.
+
+-module(http_controller_handler).
+
+-behavior(cowboy_rest).
+
+-export([init/2, content_types_provided/2, handle_request_json/2,
+         allowed_methods/2, delete_resource/2, content_types_accepted/2]).
+
+-ignore_xref([handle_request_json/2]).
+
+-include_lib("kernel/include/logger.hrl").
+
+-define(POST, <<"POST">>).
+-define(HTTP_200, 200).
+-define(HTTP_400, 400).
+-define(CONTENT_TYPE_PROBLEM_JSON, #{<<"content-type">> => "application/problem+json"}).
+
+init(Req0, State) ->
+    case cowboy_req:version(Req0) of
+        'HTTP/2' ->
+            {cowboy_rest, Req0, State};
+        _ ->
+            Body = jsx:encode(#{
+                title  => <<"HTTP/2 is mandatory.">>,
+                status => ?HTTP_400,
+                cause  => <<"UNSUPPORTED_HTTP_VERSION">>
+            }),
+            Req = cowboy_req:reply(?HTTP_400, ?CONTENT_TYPE_PROBLEM_JSON, Body, Req0),
+            {ok, Req, done}
+    end.
+
+allowed_methods(Req, State) ->
+    {[?POST], Req, State}.
+
+content_types_provided(Req, State) ->
+    {[{<<"application/json">>, handle_request_json}], Req, State}.
+
+content_types_accepted(Req, State) ->
+    {[{'*', handle_request_json}], Req, State}.
+
+delete_resource(Req, State) ->
+    Path = cowboy_req:path(Req),
+    Method = cowboy_req:method(Req),
+    handle_request(Method, Path, Req, State).
+
+handle_request_json(Req, State) ->
+    Path = cowboy_req:path(Req),
+    Method = cowboy_req:method(Req),
+    handle_request(Method, Path, Req, State).
+
+%%%===================================================================
+%%% Handler of request
+%%%===================================================================
+
+handle_request(?POST, <<"/api/v1/controller">>, Req0, State) ->
+    {ok, Body, Req} = read_body(Req0),
+    case validate_json_req(Body) of
+        {ok, Response} ->
+            reply(?HTTP_200, Req, jsx:encode(Response), State);
+        {error, invalid_json} ->
+            Response = rfc7807(<<"Invalid JSON">>, <<"INVALID_JSON">>, []),
+            reply(?HTTP_400, Req, Response, State);
+        {error, InvalidParams} ->
+            Response = rfc7807(<<"Invalid JSON params">>, <<"INVALID_JSON_PARAM">>, InvalidParams),
+            reply(?HTTP_400, Req, Response, State)
+    end.
+
+%%%===================================================================
+%%% Helper functions
+%%%===================================================================
+
+validate_json_req(JsonBin) ->
+    case json_to_map(JsonBin) of
+        {ok, Map} ->
+            apply_config(Map);
+        Error ->
+            Error
+    end.
+
+% Jesse errors: https://github.com/for-GET/jesse/blob/1.5.6/src/jesse_error.erl#L40
+apply_config(Map) ->
+    case catch ergw_config:load_part_of_config(Map) of
+        {ok, Config} ->
+            _ = maps:fold(fun add_config_part/3, #{}, Config),
+            % @TODO for response collect all keys of config what was successfully applied
+            {ok, #{type => <<"success">>}};
+        {error, [_|_] = Error} = Reason ->
+            ?LOG(warning, "~p", [Reason]),
+            Params = build_error_params(Error),
+            {error, Params};
+        Error ->
+            ?LOG(warning, "Unhandled error ~p~nfor config ~p", [Error, Map]),
+            {error, []}
+    end.
+
+build_error_params(Data) ->
+    build_error_params(Data, []).
+
+build_error_params([], Acc) ->
+    Acc;
+build_error_params([{Type, Schema, Error, Data, Path}|T], Acc) ->
+    I = #{
+        type => atom_to_binary(Type),
+        schema => Schema,
+        error => atom_to_binary(Error),
+        data => Data,
+        path => Path
+    },
+    build_error_params(T, [I|Acc]).
+
+add_config_part(K, V, Acc) ->
+    Result = ergw_config:ergw_core_init(K, #{K => V}),
+    ?LOG(info, "The ~p added with result ~p", [K, Result]),
+    maps:merge(Acc, Result).
+
+json_to_map(JsonBin) ->
+    case catch jsx:decode(JsonBin) of
+        #{} = Map ->
+            {ok, Map};
+        _ ->
+            {error, invalid_json}
+    end.
+
+read_body(Req) ->
+    read_body(Req, <<>>).
+
+read_body(Req0, Acc) ->
+    case cowboy_req:read_body(Req0) of
+        {ok, Data, Req} ->
+            {ok, <<Acc/binary, Data/binary>>, Req};
+        {more, Data, Req} ->
+            read_body(Req, <<Acc/binary, Data/binary>>)
+    end.
+
+reply(StatusCode, Req0, Body, State) ->
+    Req = case StatusCode of
+        ?HTTP_200 ->
+            cowboy_req:reply(StatusCode, #{}, Body, Req0);
+        ?HTTP_400 ->
+            cowboy_req:reply(StatusCode, ?CONTENT_TYPE_PROBLEM_JSON, Body, Req0)
+    end,
+    {stop, Req, State}.
+
+%% https://datatracker.ietf.org/doc/html/rfc7807
+rfc7807(Title, Cause, []) ->
+    jsx:encode(#{
+        title  => Title,
+        status => ?HTTP_400,
+        cause  => Cause
+    });
+rfc7807(Title, Cause, InvalidParams) ->
+    jsx:encode(#{
+        title  => Title,
+        status => ?HTTP_400,
+        cause  => Cause,
+        'invalid-params' => InvalidParams
+    }).