apply COUCHDB-252.

Allow _list functions to signal that iteration of the view should cease.
Thanks davisp.


git-svn-id: https://svn.apache.org/repos/asf/couchdb/trunk@744240 13f79535-47bb-0310-9956-ffa450edef68

4 files changed, 18 insertions, 7 deletions

diff --git a/src/couchdb/couch_db.hrl b/src/couchdb/couch_db.hrl
index 1afea912..5b8b74ef 100644
--- a/src/couchdb/couch_db.hrl
+++ b/src/couchdb/couch_db.hrl
@@ -162,6 +162,7 @@
 
 -record(extern_resp_args, {
     code = 200,
+    stop = false,
     data = <<>>,
     ctype = "application/json",
     headers = []
diff --git a/src/couchdb/couch_httpd_external.erl b/src/couchdb/couch_httpd_external.erl
index 5f63ac0e..2e25705b 100644
--- a/src/couchdb/couch_httpd_external.erl
+++ b/src/couchdb/couch_httpd_external.erl
@@ -106,6 +106,8 @@ parse_external_response({Response}) ->
                 Args;
             {<<"code">>, Value} ->
                 Args#extern_resp_args{code=Value};
+            {<<"stop">>, true} ->
+                Args#extern_resp_args{stop=true};
             {<<"json">>, Value} ->
                 Args#extern_resp_args{
                     data=?JSON_ENCODE(Value),
diff --git a/src/couchdb/couch_httpd_show.erl b/src/couchdb/couch_httpd_show.erl
index 2771a1c9..1da8fe98 100644
--- a/src/couchdb/couch_httpd_show.erl
+++ b/src/couchdb/couch_httpd_show.erl
@@ -127,13 +127,17 @@ output_map_list(Req, Lang, ListSrc, View, Db, QueryArgs) ->
         JsonResp = couch_query_servers:render_list_row(QueryServer, 
             Req, Db2, {{Key, DocId}, Value}),
         #extern_resp_args{
+            stop = StopIter,
             data = RowBody
         } = couch_httpd_external:parse_external_response(JsonResp),
         RowFront2 = case RowFront of
         nil -> [];
         _ -> RowFront
         end,
-        send_chunk(Resp, RowFront2 ++ binary_to_list(RowBody))
+        case StopIter of
+        true -> stop;
+        _ -> send_chunk(Resp, RowFront2 ++ binary_to_list(RowBody))
+        end
     end,
     
     FoldlFun = couch_httpd_view:make_view_fold_fun(Req, QueryArgs, Db, RowCount,
diff --git a/src/couchdb/couch_httpd_view.erl b/src/couchdb/couch_httpd_view.erl
index 7696bb0d..2674754e 100644
--- a/src/couchdb/couch_httpd_view.erl
+++ b/src/couchdb/couch_httpd_view.erl
@@ -416,13 +416,17 @@ make_view_fold_fun(Req, QueryArgs, Db,
             Offset = ReduceCountFun(OffsetReds),
             {ok, Resp2, BeginBody} = StartRespFun(Req, 200, 
                 TotalViewCount, Offset),
-            SendRowFun(Resp2, Db, 
-                {{Key, DocId}, Value}, BeginBody, IncludeDocs),
-            {ok, {AccLimit - 1, 0, Resp2, AccRevRows}};
+            case SendRowFun(Resp2, Db, 
+                {{Key, DocId}, Value}, BeginBody, IncludeDocs) of
+            stop ->  {stop, {AccLimit - 1, 0, Resp2, AccRevRows}};
+            _ -> {ok, {AccLimit - 1, 0, Resp2, AccRevRows}}
+            end;
         {_, AccLimit, _, Resp} when (AccLimit > 0) ->
-            SendRowFun(Resp, Db, 
-                {{Key, DocId}, Value}, nil, IncludeDocs),
-            {ok, {AccLimit - 1, 0, Resp, AccRevRows}}
+            case SendRowFun(Resp, Db, 
+                {{Key, DocId}, Value}, nil, IncludeDocs) of
+            stop ->  {stop, {AccLimit - 1, 0, Resp, AccRevRows}};
+            _ -> {ok, {AccLimit - 1, 0, Resp, AccRevRows}}
+            end
         end
     end.