| % 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. |
| |
| -module(chttpd_prefer_header). |
| |
| -compile(tuple_calls). |
| |
| -export([ |
| maybe_return_minimal/2 |
| ]). |
| |
| -include_lib("couch/include/couch_db.hrl"). |
| |
| -define(DEFAULT_PREFER_MINIMAL, |
| "Cache-Control, Content-Length, Content-Range, " |
| "Content-Type, ETag, Server, Transfer-Encoding, Vary" |
| ). |
| |
| maybe_return_minimal(#httpd{mochi_req = MochiReq}, Headers) -> |
| case get_prefer_header(MochiReq) of |
| "return=minimal" -> |
| filter_headers(Headers, get_header_list()); |
| _ -> |
| Headers |
| end. |
| |
| get_prefer_header(Req) -> |
| case Req:get_header_value("Prefer") of |
| Value when is_list(Value) -> |
| string:to_lower(Value); |
| undefined -> |
| undefined |
| end. |
| |
| filter_headers(Headers, IncludeList) -> |
| lists:filter( |
| fun({HeaderName, _}) -> |
| lists:member(HeaderName, IncludeList) |
| end, |
| Headers |
| ). |
| |
| get_header_list() -> |
| SectionStr = config:get( |
| "chttpd", |
| "prefer_minimal", |
| ?DEFAULT_PREFER_MINIMAL |
| ), |
| split_list(SectionStr). |
| |
| split_list(S) -> |
| re:split(S, "\\s*,\\s*", [trim, {return, list}]). |