Merge pull request #3129 from apache/delay_response_until_end
Add option to delay responses until the end
diff --git a/rel/overlay/etc/default.ini b/rel/overlay/etc/default.ini
index f3f12ca..16d568f 100644
--- a/rel/overlay/etc/default.ini
+++ b/rel/overlay/etc/default.ini
@@ -130,6 +130,9 @@
; _dbs_info in a request
max_db_number_for_dbs_info_req = 100
+; set to true to delay the start of a response until the end has been calculated
+;buffer_response = false
+
; authentication handlers
; authentication_handlers = {chttpd_auth, cookie_authentication_handler}, {chttpd_auth, default_authentication_handler}
; uncomment the next line to enable proxy authentication
diff --git a/src/chttpd/src/chttpd.erl b/src/chttpd/src/chttpd.erl
index adde073..fb7d61a 100644
--- a/src/chttpd/src/chttpd.erl
+++ b/src/chttpd/src/chttpd.erl
@@ -52,8 +52,9 @@
req,
code,
headers,
- first_chunk,
- resp=nil
+ chunks,
+ resp=nil,
+ buffer_response=false
}).
start_link() ->
@@ -780,40 +781,54 @@
end_json_response(Resp) ->
couch_httpd:end_json_response(Resp).
+
start_delayed_json_response(Req, Code) ->
start_delayed_json_response(Req, Code, []).
+
start_delayed_json_response(Req, Code, Headers) ->
start_delayed_json_response(Req, Code, Headers, "").
+
start_delayed_json_response(Req, Code, Headers, FirstChunk) ->
{ok, #delayed_resp{
start_fun = fun start_json_response/3,
req = Req,
code = Code,
headers = Headers,
- first_chunk = FirstChunk}}.
+ chunks = [FirstChunk],
+ buffer_response = buffer_response(Req)}}.
+
start_delayed_chunked_response(Req, Code, Headers) ->
start_delayed_chunked_response(Req, Code, Headers, "").
+
start_delayed_chunked_response(Req, Code, Headers, FirstChunk) ->
{ok, #delayed_resp{
start_fun = fun start_chunked_response/3,
req = Req,
code = Code,
headers = Headers,
- first_chunk = FirstChunk}}.
+ chunks = [FirstChunk],
+ buffer_response = buffer_response(Req)}}.
-send_delayed_chunk(#delayed_resp{}=DelayedResp, Chunk) ->
+
+send_delayed_chunk(#delayed_resp{buffer_response=false}=DelayedResp, Chunk) ->
{ok, #delayed_resp{resp=Resp}=DelayedResp1} =
start_delayed_response(DelayedResp),
{ok, Resp} = send_chunk(Resp, Chunk),
- {ok, DelayedResp1}.
+ {ok, DelayedResp1};
+
+send_delayed_chunk(#delayed_resp{buffer_response=true}=DelayedResp, Chunk) ->
+ #delayed_resp{chunks = Chunks} = DelayedResp,
+ {ok, DelayedResp#delayed_resp{chunks = [Chunk | Chunks]}}.
+
send_delayed_last_chunk(Req) ->
send_delayed_chunk(Req, []).
+
send_delayed_error(#delayed_resp{req=Req,resp=nil}=DelayedResp, Reason) ->
{Code, ErrorStr, ReasonStr} = error_info(Reason),
{ok, Resp} = send_error(Req, Code, ErrorStr, ReasonStr),
@@ -823,6 +838,7 @@
log_error_with_stack_trace(Reason),
throw({http_abort, Resp, Reason}).
+
close_delayed_json_object(Resp, Buffer, Terminator, 0) ->
% Use a separate chunk to close the streamed array to maintain strict
% compatibility with earlier versions. See COUCHDB-2724
@@ -831,10 +847,22 @@
close_delayed_json_object(Resp, Buffer, Terminator, _Threshold) ->
send_delayed_chunk(Resp, [Buffer | Terminator]).
-end_delayed_json_response(#delayed_resp{}=DelayedResp) ->
+
+end_delayed_json_response(#delayed_resp{buffer_response=false}=DelayedResp) ->
{ok, #delayed_resp{resp=Resp}} =
start_delayed_response(DelayedResp),
- end_json_response(Resp).
+ end_json_response(Resp);
+
+end_delayed_json_response(#delayed_resp{buffer_response=true}=DelayedResp) ->
+ #delayed_resp{
+ req = Req,
+ code = Code,
+ headers = Headers,
+ chunks = Chunks
+ } = DelayedResp,
+ {ok, Resp} = start_response_length(Req, Code, Headers, iolist_size(Chunks)),
+ send(Resp, lists:reverse(Chunks)).
+
get_delayed_req(#delayed_resp{req=#httpd{mochi_req=MochiReq}}) ->
MochiReq;
@@ -847,7 +875,7 @@
req=Req,
code=Code,
headers=Headers,
- first_chunk=FirstChunk
+ chunks=[FirstChunk]
}=DelayedResp,
{ok, Resp} = StartFun(Req, Code, Headers),
case FirstChunk of
@@ -858,6 +886,18 @@
start_delayed_response(#delayed_resp{}=DelayedResp) ->
{ok, DelayedResp}.
+
+buffer_response(Req) ->
+ case chttpd:qs_value(Req, "buffer_response") of
+ "false" ->
+ false;
+ "true" ->
+ true;
+ _ ->
+ config:get_boolean("chttpd", "buffer_response", false)
+ end.
+
+
error_info({Error, Reason}) when is_list(Reason) ->
error_info({Error, couch_util:to_binary(Reason)});
error_info(bad_request) ->
diff --git a/src/chttpd/test/eunit/chttpd_delayed_test.erl b/src/chttpd/test/eunit/chttpd_delayed_test.erl
new file mode 100644
index 0000000..64232dc
--- /dev/null
+++ b/src/chttpd/test/eunit/chttpd_delayed_test.erl
@@ -0,0 +1,73 @@
+-module(chttpd_delayed_test).
+
+-include_lib("couch/include/couch_eunit.hrl").
+-include_lib("couch/include/couch_db.hrl").
+
+-define(USER, "chttpd_view_test_admin").
+-define(PASS, "pass").
+-define(AUTH, {basic_auth, {?USER, ?PASS}}).
+-define(CONTENT_JSON, {"Content-Type", "application/json"}).
+-define(DDOC, "{\"_id\": \"_design/bar\", \"views\": {\"baz\":
+ {\"map\": \"function(doc) {emit(doc._id, doc._id);}\"}}}").
+
+-define(FIXTURE_TXT, ?ABS_PATH(?FILE)).
+-define(i2l(I), integer_to_list(I)).
+-define(TIMEOUT, 60). % seconds
+
+setup() ->
+ Hashed = couch_passwords:hash_admin_password(?PASS),
+ ok = config:set("admins", ?USER, ?b2l(Hashed), _Persist=false),
+ ok = config:set("chttpd", "buffer_response", "true"),
+ TmpDb = ?tempdb(),
+ Addr = config:get("chttpd", "bind_address", "127.0.0.1"),
+ Port = mochiweb_socket_server:get(chttpd, port),
+ Url = lists:concat(["http://", Addr, ":", Port, "/", ?b2l(TmpDb)]),
+ create_db(Url),
+ Url.
+
+teardown(Url) ->
+ delete_db(Url),
+ ok = config:delete("admins", ?USER, _Persist=false).
+
+create_db(Url) ->
+ {ok, Status, _, _} = test_request:put(Url, [?CONTENT_JSON, ?AUTH], "{}"),
+ ?assert(Status =:= 201 orelse Status =:= 202).
+
+
+delete_db(Url) ->
+ {ok, 200, _, _} = test_request:delete(Url, [?AUTH]).
+
+
+all_test_() ->
+ {
+ "chttpd delay tests",
+ {
+ setup,
+ fun chttpd_test_util:start_couch/0, fun chttpd_test_util:stop_couch/1,
+ {
+ foreach,
+ fun setup/0, fun teardown/1,
+ [
+ fun test_buffer_response_all_docs/1,
+ fun test_buffer_response_changes/1
+ ]
+ }
+ }
+ }.
+
+
+test_buffer_response_all_docs(Url) ->
+ assert_has_content_length(Url ++ "/_all_docs").
+
+
+test_buffer_response_changes(Url) ->
+ assert_has_content_length(Url ++ "/_changes").
+
+
+assert_has_content_length(Url) ->
+ {timeout, ?TIMEOUT, ?_test(begin
+ {ok, Code, Headers, _Body} = test_request:get(Url, [?AUTH]),
+ ?assertEqual(200, Code),
+ ?assert(lists:keymember("Content-Length", 1, Headers))
+ end)}.
+
\ No newline at end of file
