summaryrefslogtreecommitdiff
path: root/apps/chttpd/src/chttpd_rewrite.erl
diff options
context:
space:
mode:
Diffstat (limited to 'apps/chttpd/src/chttpd_rewrite.erl')
-rw-r--r--apps/chttpd/src/chttpd_rewrite.erl418
1 files changed, 0 insertions, 418 deletions
diff --git a/apps/chttpd/src/chttpd_rewrite.erl b/apps/chttpd/src/chttpd_rewrite.erl
deleted file mode 100644
index fbf246ab..00000000
--- a/apps/chttpd/src/chttpd_rewrite.erl
+++ /dev/null
@@ -1,418 +0,0 @@
-% Licensed under the Apache License, Version 2.0 (the "License"); you may not
-% use this file except in compliance with the License. You may obtain a copy of
-% the License at
-%
-% http://www.apache.org/licenses/LICENSE-2.0
-%
-% Unless required by applicable law or agreed to in writing, software
-% distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
-% WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
-% License for the specific language governing permissions and limitations under
-% the License.
-%
-% bind_path is based on bind method from Webmachine
-
-
-%% @doc Module for URL rewriting by pattern matching.
-
--module(chttpd_rewrite).
--export([handle_rewrite_req/3]).
--include_lib("couch/include/couch_db.hrl").
-
--define(SEPARATOR, $\/).
--define(MATCH_ALL, '*').
-
-
-%% doc The http rewrite handler. All rewriting is done from
-%% /dbname/_design/ddocname/_rewrite by default.
-%%
-%% each rules should be in rewrites member of the design doc.
-%% Ex of a complete rule :
-%%
-%% {
-%% ....
-%% "rewrites": [
-%% {
-%% "from": "",
-%% "to": "index.html",
-%% "method": "GET",
-%% "query": {}
-%% }
-%% ]
-%% }
-%%
-%% from: is the path rule used to bind current uri to the rule. It
-%% use pattern matching for that.
-%%
-%% to: rule to rewrite an url. It can contain variables depending on binding
-%% variables discovered during pattern matching and query args (url args and from
-%% the query member.)
-%%
-%% method: method to bind the request method to the rule. by default "*"
-%% query: query args you want to define they can contain dynamic variable
-%% by binding the key to the bindings
-%%
-%%
-%% to and from are path with patterns. pattern can be string starting with ":" or
-%% "*". ex:
-%% /somepath/:var/*
-%%
-%% This path is converted in erlang list by splitting "/". Each var are
-%% converted in atom. "*" is converted to '*' atom. The pattern matching is done
-%% by splitting "/" in request url in a list of token. A string pattern will
-%% match equal token. The star atom ('*' in single quotes) will match any number
-%% of tokens, but may only be present as the last pathtern in a pathspec. If all
-%% tokens are matched and all pathterms are used, then the pathspec matches. It works
-%% like webmachine. Each identified token will be reused in to rule and in query
-%%
-%% The pattern matching is done by first matching the request method to a rule. by
-%% default all methods match a rule. (method is equal to "*" by default). Then
-%% It will try to match the path to one rule. If no rule match, then a 404 error
-%% is displayed.
-%%
-%% Once a rule is found we rewrite the request url using the "to" and
-%% "query" members. The identified token are matched to the rule and
-%% will replace var. if '*' is found in the rule it will contain the remaining
-%% part if it exists.
-%%
-%% Examples:
-%%
-%% Dispatch rule URL TO Tokens
-%%
-%% {"from": "/a/b", /a/b?k=v /some/b?k=v var =:= b
-%% "to": "/some/"} k = v
-%%
-%% {"from": "/a/b", /a/b /some/b?var=b var =:= b
-%% "to": "/some/:var"}
-%%
-%% {"from": "/a", /a /some
-%% "to": "/some/*"}
-%%
-%% {"from": "/a/*", /a/b/c /some/b/c
-%% "to": "/some/*"}
-%%
-%% {"from": "/a", /a /some
-%% "to": "/some/*"}
-%%
-%% {"from": "/a/:foo/*", /a/b/c /some/b/c?foo=b foo =:= b
-%% "to": "/some/:foo/*"}
-%%
-%% {"from": "/a/:foo", /a/b /some/?k=b&foo=b foo =:= b
-%% "to": "/some",
-%% "query": {
-%% "k": ":foo"
-%% }}
-%%
-%% {"from": "/a", /a?foo=b /some/b foo =:= b
-%% "to": "/some/:foo",
-%% }}
-
-
-
-handle_rewrite_req(#httpd{
- path_parts=[DbName, <<"_design">>, DesignName, _Rewrite|PathParts],
- method=Method,
- mochi_req=MochiReq}=Req, _Db, DDoc) ->
-
- % we are in a design handler
- DesignId = <<"_design/", DesignName/binary>>,
- Prefix = <<"/", DbName/binary, "/", DesignId/binary>>,
- QueryList = couch_httpd:qs(Req),
- QueryList1 = [{to_atom(K), V} || {K, V} <- QueryList],
-
- #doc{body={Props}} = DDoc,
-
- % get rules from ddoc
- case couch_util:get_value(<<"rewrites">>, Props) of
- undefined ->
- couch_httpd:send_error(Req, 404, <<"rewrite_error">>,
- <<"Invalid path.">>);
- Rules ->
- % create dispatch list from rules
- DispatchList = [make_rule(Rule) || {Rule} <- Rules],
-
- %% get raw path by matching url to a rule.
- RawPath = case try_bind_path(DispatchList, Method, PathParts,
- QueryList1) of
- no_dispatch_path ->
- throw(not_found);
- {NewPathParts, Bindings} ->
- Parts = [mochiweb_util:quote_plus(X) || X <- NewPathParts],
-
- % build new path, reencode query args, eventually convert
- % them to json
- Path = lists:append(
- string:join(Parts, [?SEPARATOR]),
- case Bindings of
- [] -> [];
- _ -> [$?, encode_query(Bindings)]
- end),
-
- % if path is relative detect it and rewrite path
- case mochiweb_util:safe_relative_path(Path) of
- undefined ->
- ?b2l(Prefix) ++ "/" ++ Path;
- P1 ->
- ?b2l(Prefix) ++ "/" ++ P1
- end
-
- end,
-
- % normalize final path (fix levels "." and "..")
- RawPath1 = ?b2l(iolist_to_binary(normalize_path(RawPath))),
-
- ?LOG_DEBUG("rewrite to ~p ~n", [RawPath1]),
-
- % build a new mochiweb request
- MochiReq1 = mochiweb_request:new(MochiReq:get(socket),
- MochiReq:get(method),
- RawPath1,
- MochiReq:get(version),
- MochiReq:get(headers)),
-
- % cleanup, It force mochiweb to reparse raw uri.
- MochiReq1:cleanup(),
-
- chttpd:handle_request(MochiReq1)
- end.
-
-
-
-%% @doc Try to find a rule matching current url. If none is found
-%% 404 error not_found is raised
-try_bind_path([], _Method, _PathParts, _QueryList) ->
- no_dispatch_path;
-try_bind_path([Dispatch|Rest], Method, PathParts, QueryList) ->
- [{PathParts1, Method1}, RedirectPath, QueryArgs] = Dispatch,
- case bind_method(Method1, Method) of
- true ->
- case bind_path(PathParts1, PathParts, []) of
- {ok, Remaining, Bindings} ->
- Bindings1 = Bindings ++ QueryList,
-
- % we parse query args from the rule and fill
- % it eventually with bindings vars
- QueryArgs1 = make_query_list(QueryArgs, Bindings1, []),
-
- % remove params in QueryLists1 that are already in
- % QueryArgs1
- Bindings2 = lists:foldl(fun({K, V}, Acc) ->
- K1 = to_atom(K),
- KV = case couch_util:get_value(K1, QueryArgs1) of
- undefined -> [{K1, V}];
- _V1 -> []
- end,
- Acc ++ KV
- end, [], Bindings1),
-
- FinalBindings = Bindings2 ++ QueryArgs1,
- NewPathParts = make_new_path(RedirectPath, FinalBindings,
- Remaining, []),
- {NewPathParts, FinalBindings};
- fail ->
- try_bind_path(Rest, Method, PathParts, QueryList)
- end;
- false ->
- try_bind_path(Rest, Method, PathParts, QueryList)
- end.
-
-%% rewriting dynamically the quey list given as query member in
-%% rewrites. Each value is replaced by one binding or an argument
-%% passed in url.
-make_query_list([], _Bindings, Acc) ->
- Acc;
-make_query_list([{Key, {Value}}|Rest], Bindings, Acc) ->
- Value1 = to_json({Value}),
- make_query_list(Rest, Bindings, [{to_atom(Key), Value1}|Acc]);
-make_query_list([{Key, Value}|Rest], Bindings, Acc) when is_binary(Value) ->
- Value1 = replace_var(Key, Value, Bindings),
- make_query_list(Rest, Bindings, [{to_atom(Key), Value1}|Acc]);
-make_query_list([{Key, Value}|Rest], Bindings, Acc) when is_list(Value) ->
- Value1 = replace_var(Key, Value, Bindings),
- make_query_list(Rest, Bindings, [{to_atom(Key), Value1}|Acc]);
-make_query_list([{Key, Value}|Rest], Bindings, Acc) ->
- make_query_list(Rest, Bindings, [{to_atom(Key), Value}|Acc]).
-
-replace_var(Key, Value, Bindings) ->
- case Value of
- <<":", Var/binary>> ->
- get_var(Var, Bindings, Value);
- _ when is_list(Value) ->
- Value1 = lists:foldr(fun(V, Acc) ->
- V1 = case V of
- <<":", VName/binary>> ->
- case get_var(VName, Bindings, V) of
- V2 when is_list(V2) ->
- iolist_to_binary(V2);
- V2 -> V2
- end;
- _ ->
-
- V
- end,
- [V1|Acc]
- end, [], Value),
- to_json(Value1);
- _ when is_binary(Value) ->
- Value;
- _ ->
- case Key of
- <<"key">> -> to_json(Value);
- <<"startkey">> -> to_json(Value);
- <<"endkey">> -> to_json(Value);
- _ ->
- lists:flatten(?JSON_ENCODE(Value))
- end
- end.
-
-
-get_var(VarName, Props, Default) ->
- VarName1 = list_to_atom(binary_to_list(VarName)),
- couch_util:get_value(VarName1, Props, Default).
-
-%% doc: build new patch from bindings. bindings are query args
-%% (+ dynamic query rewritten if needed) and bindings found in
-%% bind_path step.
-make_new_path([], _Bindings, _Remaining, Acc) ->
- lists:reverse(Acc);
-make_new_path([?MATCH_ALL], _Bindings, Remaining, Acc) ->
- Acc1 = lists:reverse(Acc) ++ Remaining,
- Acc1;
-make_new_path([?MATCH_ALL|_Rest], _Bindings, Remaining, Acc) ->
- Acc1 = lists:reverse(Acc) ++ Remaining,
- Acc1;
-make_new_path([P|Rest], Bindings, Remaining, Acc) when is_atom(P) ->
- P2 = case couch_util:get_value(P, Bindings) of
- undefined -> << "undefined">>;
- P1 -> P1
- end,
- make_new_path(Rest, Bindings, Remaining, [P2|Acc]);
-make_new_path([P|Rest], Bindings, Remaining, Acc) ->
- make_new_path(Rest, Bindings, Remaining, [P|Acc]).
-
-
-%% @doc If method of the query fith the rule method. If the
-%% method rule is '*', which is the default, all
-%% request method will bind. It allows us to make rules
-%% depending on HTTP method.
-bind_method(?MATCH_ALL, _Method) ->
- true;
-bind_method(Method, Method) ->
- true;
-bind_method(_, _) ->
- false.
-
-
-%% @doc bind path. Using the rule from we try to bind variables given
-%% to the current url by pattern matching
-bind_path([], [], Bindings) ->
- {ok, [], Bindings};
-bind_path([?MATCH_ALL], Rest, Bindings) when is_list(Rest) ->
- {ok, Rest, Bindings};
-bind_path(_, [], _) ->
- fail;
-bind_path([Token|RestToken],[Match|RestMatch],Bindings) when is_atom(Token) ->
- bind_path(RestToken, RestMatch, [{Token, Match}|Bindings]);
-bind_path([Token|RestToken], [Token|RestMatch], Bindings) ->
- bind_path(RestToken, RestMatch, Bindings);
-bind_path(_, _, _) ->
- fail.
-
-
-%% normalize path.
-normalize_path(Path) ->
- "/" ++ string:join(normalize_path1(string:tokens(Path,
- "/"), []), [?SEPARATOR]).
-
-
-normalize_path1([], Acc) ->
- lists:reverse(Acc);
-normalize_path1([".."|Rest], Acc) ->
- Acc1 = case Acc of
- [] -> [".."|Acc];
- [T|_] when T =:= ".." -> [".."|Acc];
- [_|R] -> R
- end,
- normalize_path1(Rest, Acc1);
-normalize_path1(["."|Rest], Acc) ->
- normalize_path1(Rest, Acc);
-normalize_path1([Path|Rest], Acc) ->
- normalize_path1(Rest, [Path|Acc]).
-
-
-%% @doc transform json rule in erlang for pattern matching
-make_rule(Rule) ->
- Method = case couch_util:get_value(<<"method">>, Rule) of
- undefined -> '*';
- M -> list_to_atom(?b2l(M))
- end,
- QueryArgs = case couch_util:get_value(<<"query">>, Rule) of
- undefined -> [];
- {Args} -> Args
- end,
- FromParts = case couch_util:get_value(<<"from">>, Rule) of
- undefined -> ['*'];
- From ->
- parse_path(From)
- end,
- ToParts = case couch_util:get_value(<<"to">>, Rule) of
- undefined ->
- throw({error, invalid_rewrite_target});
- To ->
- parse_path(To)
- end,
- [{FromParts, Method}, ToParts, QueryArgs].
-
-parse_path(Path) ->
- {ok, SlashRE} = re:compile(<<"\\/">>),
- path_to_list(re:split(Path, SlashRE), [], 0).
-
-%% @doc convert a path rule (from or to) to an erlang list
-%% * and path variable starting by ":" are converted
-%% in erlang atom.
-path_to_list([], Acc, _DotDotCount) ->
- lists:reverse(Acc);
-path_to_list([<<>>|R], Acc, DotDotCount) ->
- path_to_list(R, Acc, DotDotCount);
-path_to_list([<<"*">>|R], Acc, DotDotCount) ->
- path_to_list(R, [?MATCH_ALL|Acc], DotDotCount);
-path_to_list([<<"..">>|R], Acc, DotDotCount) when DotDotCount == 2 ->
- case couch_config:get("httpd", "secure_rewrites", "true") of
- "false" ->
- path_to_list(R, [<<"..">>|Acc], DotDotCount+1);
- _Else ->
- ?LOG_INFO("insecure_rewrite_rule ~p blocked", [lists:reverse(Acc) ++ [<<"..">>] ++ R]),
- throw({insecure_rewrite_rule, "too many ../.. segments"})
- end;
-path_to_list([<<"..">>|R], Acc, DotDotCount) ->
- path_to_list(R, [<<"..">>|Acc], DotDotCount+1);
-path_to_list([P|R], Acc, DotDotCount) ->
- P1 = case P of
- <<":", Var/binary>> ->
- list_to_atom(binary_to_list(Var));
- _ -> P
- end,
- path_to_list(R, [P1|Acc], DotDotCount).
-
-encode_query(Props) ->
- Props1 = lists:foldl(fun ({K, V}, Acc) ->
- V1 = case is_list(V) of
- true -> V;
- false when is_binary(V) ->
- V;
- false ->
- mochiweb_util:quote_plus(V)
- end,
- [{K, V1} | Acc]
- end, [], Props),
- lists:flatten(mochiweb_util:urlencode(Props1)).
-
-to_atom(V) when is_atom(V) ->
- V;
-to_atom(V) when is_binary(V) ->
- to_atom(?b2l(V));
-to_atom(V) ->
- list_to_atom(V).
-
-to_json(V) ->
- iolist_to_binary(?JSON_ENCODE(V)).