%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2005-2016. All Rights Reserved.
%%
%% 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.
%%
%% %CopyrightEnd%
%%
%%
-module(httpd_esi).
-export([parse_headers/1, handle_headers/1]).
-include_lib("inets/src/inets_app/inets_internal.hrl").
%%%=========================================================================
%%% Internal application API
%%%=========================================================================
%%--------------------------------------------------------------------------
%% parse_headers(Data) -> {Headers, Body}
%%
%% Data = string() | io_list()
%% Headers = string()
%% Body = io_list()
%%
%% Description: Parses <Data> and divides it to a header part and a
%% body part. Note that it is presumed that <Data> starts with a
%% string including "\r\n\r\n" if there is any header information
%% present. The returned headers will not contain the HTTP header body
%% delimiter \r\n. (All header, header delimiters are kept.)
%% Ex: ["Content-Type : text/html\r\n Connection : closing \r\n\r\n" |
%% io_list()] --> {"Content-Type : text/html\r\n Connection : closing \r\n",
%% io_list()}
%%--------------------------------------------------------------------------
parse_headers(Data) ->
parse_headers(Data, []).
%%--------------------------------------------------------------------------
%% handle_headers(Headers) -> {ok, HTTPHeaders, StatusCode} |
%% {proceed, AbsPath}
%% Headers = string()
%% HTTPHeaders = [{HeaderField, HeaderValue}]
%% HeaderField = string()
%% HeaderValue = string()
%% StatusCode = integer()
%%
%% Description: Transforms the plain HTTP header string data received
%% from the ESI program into a list of header values and an
%% appropriate HTTP status code. Note if a location header is present
%% the return value will be {proceed, AbsPath}
%%--------------------------------------------------------------------------
handle_headers("") ->
{ok, [], 200};
handle_headers(Headers) ->
NewHeaders = string:tokens(Headers, ?CRLF),
handle_headers(NewHeaders, [], 200, true).
%%%========================================================================
%%% Internal functions
%%%========================================================================
parse_headers([], Acc) ->
{[], lists:reverse(Acc)};
parse_headers([?CR, ?LF, ?CR, ?LF], Acc) ->
{lists:reverse(Acc) ++ [?CR, ?LF], []};
parse_headers([?CR, ?LF, ?CR, ?LF | Rest], Acc) ->
{lists:reverse(Acc) ++ [?CR, ?LF], Rest};
parse_headers([Char | Rest], Acc) ->
parse_headers(Rest, [Char | Acc]).
handle_headers([], NewHeaders, StatusCode, _) ->
{ok, NewHeaders, StatusCode};
handle_headers([Header | Headers], NewHeaders, StatusCode, NoESIStatus) ->
{FieldName, FieldValue} = httpd_response:split_header(Header, []),
case FieldName of
"location" ->
handle_headers(Headers,
[{FieldName, FieldValue} | NewHeaders],
302, NoESIStatus);
"status" ->
NewStatusCode =
case httpd_util:split(FieldValue," ",2) of
{ok,[Code,_]} ->
list_to_integer(Code);
_ ->
200
end,
handle_headers(Headers, NewHeaders, NewStatusCode, false);
_ ->
handle_headers(Headers,
[{FieldName, FieldValue}| NewHeaders], StatusCode,
NoESIStatus)
end.
