From ac3d047a6be45316681d9c6e507537231d1e0e0a Mon Sep 17 00:00:00 2001 From: Adam Kocoloski Date: Fri, 24 Jul 2009 16:38:53 +0000 Subject: reassemble split chunks in changes feed, add all() export git-svn-id: https://svn.apache.org/repos/asf/couchdb/trunk@797553 13f79535-47bb-0310-9956-ffa450edef68 --- src/couchdb/couch_rep_changes_feed.erl | 123 ++++++++++++++++++++++++++------- 1 file changed, 97 insertions(+), 26 deletions(-) (limited to 'src/couchdb/couch_rep_changes_feed.erl') diff --git a/src/couchdb/couch_rep_changes_feed.erl b/src/couchdb/couch_rep_changes_feed.erl index deea2d8e..3de178a5 100644 --- a/src/couchdb/couch_rep_changes_feed.erl +++ b/src/couchdb/couch_rep_changes_feed.erl @@ -15,7 +15,7 @@ -export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2, code_change/3]). --export([start/2, start_link/2, next/1, stop/1]). +-export([start/2, start_link/2, all/1, next/1, stop/1]). -define(MIN_BUFFER_SIZE, 100). @@ -23,10 +23,12 @@ -include("../ibrowse/ibrowse.hrl"). -record (remote, { - conn = nil, - reqid = nil, + conn, + reqid, + last_seq, complete = false, count = 0, + partial_chunk = nil, reply_to = nil, rows = queue:new() }). @@ -46,6 +48,11 @@ start(Url, Options) -> start_link(Url, Options) -> gen_server:start_link(?MODULE, [Url, Options], []). +%% @doc does not block +all(Server) -> + gen_server:call(Server, all_changes). + +%% @doc returns the next change from the feed, blocking if necessary next(Server) -> gen_server:call(Server, next_change, infinity). @@ -57,7 +64,7 @@ init([{remote, Url}, Options]) -> Continuous = proplists:get_value(continuous, Options, false), {Pid, ReqId} = start_http_request(lists:concat([Url, "/_changes", "?style=all_docs", "&since=", Since, "&continuous=", Continuous])), - {ok, #remote{conn=Pid, reqid=ReqId}}; + {ok, #remote{conn=Pid, last_seq=Since, reqid=ReqId}}; init([{local, DbName}, Options]) when is_list(DbName) -> init([{local, ?l2b(DbName)}, Options]); @@ -91,6 +98,30 @@ handle_call({add, Row}, From, #local{}=State) -> } = State, {noreply, State#local{count=Count+1, changes_from=From, rows=queue:in(Row,Rows)}}; +handle_call(all_changes, _From, #local{complete=Complete, count=Count}=State) + when Complete =:= false; Count > 0 -> + #local{ + changes_from = ChangesFrom, + rows = Rows + } = State, + if Count < ?MIN_BUFFER_SIZE, ChangesFrom =/= nil -> + gen_server:reply(ChangesFrom, ok); + true -> ok end, + {reply, queue:to_list(Rows), State#local{count=0, rows=queue:new()}}; +handle_call(all_changes, _From, #local{}=State) -> + {stop, normal, complete, State}; + +handle_call(all_changes, _From, #remote{complete=Complete, count=Count}=State) + when Complete =:= false; Count > 0 -> + #remote{ + reqid = Id, + rows = Rows + } = State, + ok = maybe_stream_next(Complete, 0, Id), + {reply, queue:to_list(Rows), State#remote{count=0, rows=queue:new()}}; +handle_call(all_changes, _From, #remote{}=State) -> + {stop, normal, complete, State}; + handle_call(next_change, From, #local{count=0}=State) -> if State#local.complete -> {stop, normal, complete, State}; @@ -158,28 +189,11 @@ handle_info({ibrowse_async_headers, Id, Code, Hdrs}, #remote{reqid=Id}=State) -> [Code,Hdrs]), {stop, {error, list_to_integer(Code)}, State}; +handle_info({ibrowse_async_response, _, {error, Reason}}, State) -> + {stop, {error, Reason}, State}; handle_info({ibrowse_async_response, Id, Msg}, #remote{reqid=Id} = State) -> ?LOG_DEBUG("~p reqid ~p ibrowse_async_response ~p", [?MODULE, Id, Msg]), - #remote{ - complete = Complete, - count = Count, - rows = Rows - } = State, - try - Row = decode_row(Msg), - case State of - #remote{reply_to=nil} -> - {noreply, State#remote{count=Count+1, rows = queue:in(Row, Rows)}}; - #remote{count=0, reply_to=From}-> - gen_server:reply(From, Row), - {noreply, State#remote{reply_to=nil}} - end - catch - throw:{invalid_json, Msg} -> - ?LOG_DEBUG("got invalid_json ~p", [Msg]), - ok = maybe_stream_next(Complete, Count, Id), - {noreply, State} - end; + {noreply, process_response(Msg, Id, State)}; handle_info({ibrowse_async_response_end, Id}, #remote{reqid=Id} = State) -> ?LOG_DEBUG("got ibrowse_async_response_end ~p", [State#remote.reply_to]), @@ -217,7 +231,63 @@ code_change(_OldVsn, State, _Extra) -> %internal funs -decode_row([$,, $\n | Rest]) -> +process_response(<<"{\"results\":[\n">>, Id, State) -> + #remote{ + complete = Complete, + count = Count + } = State, + ok = maybe_stream_next(Complete, Count, Id), + State; +process_response(<<"\n],\n\"last_seq\":", LastSeqStr/binary>>, _, State) -> + LastSeq = list_to_integer(?b2l(hd(re:split(LastSeqStr, "}")))), + State#remote{last_seq = LastSeq}; +process_response(Chunk, Id, #remote{partial_chunk=nil} = State) -> + #remote{ + complete = Complete, + count = Count, + rows = Rows + } = State, + try + Row = decode_row(Chunk), + ok = maybe_stream_next(Complete, Count+1, Id), + case State of + #remote{reply_to=nil} -> + State#remote{count=Count+1, rows = queue:in(Row, Rows)}; + #remote{count=0, reply_to=From}-> + gen_server:reply(From, Row), + State#remote{reply_to=nil} + end + catch + throw:{invalid_json, Bad} -> + ?LOG_DEBUG("got invalid_json ~p", [Bad]), + ok = maybe_stream_next(Complete, Count, Id), + State#remote{partial_chunk = Bad} + end; +process_response(Chunk, Id, State) -> + #remote{ + complete = Complete, + count = Count, + partial_chunk = Partial, + rows = Rows + } = State, + try + Row = decode_row(<>), + ok = maybe_stream_next(Complete, Count+1, Id), + case State of + #remote{reply_to=nil} -> + State#remote{count=Count+1, partial_chunk=nil, rows=queue:in(Row,Rows)}; + #remote{count=0, reply_to=From}-> + gen_server:reply(From, Row), + State#remote{reply_to=nil, partial_chunk=nil} + end + catch + throw:{invalid_json, Bad} -> + ?LOG_DEBUG("got invalid_json ~p", [Bad]), + ok = maybe_stream_next(Complete, Count, Id), + State#remote{partial_chunk = Bad} + end. + +decode_row(<<",\n", Rest/binary>>) -> decode_row(Rest); decode_row(Row) -> ?JSON_DECODE(Row). @@ -278,7 +348,8 @@ start_http_request(RawUrl) -> {ok, Pid} = ibrowse:spawn_link_worker_process(Url#url.host, Url#url.port), Opts = [ {stream_to, {self(), once}}, - {inactivity_timeout, 30000} + {inactivity_timeout, 30000}, + {response_format, binary} ], {ibrowse_req_id, Id} = ibrowse:send_req_direct(Pid, RawUrl, [], get, [], Opts, infinity), -- cgit v1.2.3