- add descriptions to metrics

- move document_* metrics to couch_db module and merge them into database_* metrics

git-svn-id: https://svn.apache.org/repos/asf/couchdb/trunk@748217 13f79535-47bb-0310-9956-ffa450edef68

4 files changed, 82 insertions, 22 deletions

diff --git a/src/couchdb/couch_db.erl b/src/couchdb/couch_db.erl
index d9caa36f..963c834b 100644
--- a/src/couchdb/couch_db.erl
+++ b/src/couchdb/couch_db.erl
@@ -92,6 +92,7 @@ open_doc(Db, IdOrDocInfo) ->
     open_doc(Db, IdOrDocInfo, []).
 
 open_doc(Db, Id, Options) ->
+    couch_stats_collector:increment({couchdb, database_reads}),
     case open_doc_int(Db, Id, Options) of
     {ok, #doc{deleted=true}=Doc} ->
         case lists:member(deleted, Options) of
@@ -105,6 +106,7 @@ open_doc(Db, Id, Options) ->
     end.
 
 open_doc_revs(Db, Id, Revs, Options) ->
+    couch_stats_collector:increment({couchdb, database_reads}),
     [Result] = open_doc_revs_int(Db, [{Id, Revs}], Options),
     Result.
 
@@ -284,6 +286,7 @@ update_docs(#db{update_pid=UpdatePid}=Db, Docs, Options) ->
     update_docs(#db{update_pid=UpdatePid}=Db, Docs, Options, true).
 
 update_docs(Db, Docs, Options, false) ->
+    couch_stats_collector:increment({couchdb, database_changes}),
     DocBuckets = group_alike_docs(Docs),
     Ids = [Id || [#doc{id=Id}|_] <- DocBuckets],
     
@@ -320,7 +323,9 @@ update_docs(Db, Docs, Options, false) ->
     write_and_commit(Db, DocBuckets2, Options);
     
 update_docs(Db, Docs, Options, true) ->
-        % go ahead and generate the new revision ids for the documents.
+    couch_stats_collector:increment({couchdb, database_changes}),
+
+    % go ahead and generate the new revision ids for the documents.
     Docs2 = lists:map(
         fun(#doc{id=Id,revs=Revs}=Doc) ->
             case Id of
diff --git a/src/couchdb/couch_httpd_db.erl b/src/couchdb/couch_httpd_db.erl
index 78339911..53eff650 100644
--- a/src/couchdb/couch_httpd_db.erl
+++ b/src/couchdb/couch_httpd_db.erl
@@ -80,7 +80,7 @@ db_req(#httpd{method='POST',path_parts=[DbName]}=Req, Db) ->
     Doc = couch_doc:from_json_obj(couch_httpd:json_body(Req)),
     DocId = couch_util:new_uuid(),
     {ok, NewRev} = couch_db:update_doc(Db, Doc#doc{id=DocId, revs=[]}, []),
-    couch_stats_collector:increment({httpd, document_creates}),
+    % couch_stats_collector:increment({httpd, document_creates}),
     DocUrl = absolute_uri(Req, 
         binary_to_list(<<"/",DbName/binary,"/",DocId/binary>>)),
     send_json(Req, 201, [{"Location", DocUrl}], {[
@@ -379,7 +379,7 @@ db_doc_req(#httpd{method='DELETE'}=Req, Db, DocId) ->
         couch_httpd:send_error(Req, 409, <<"missing_rev">>,
             <<"Document rev/etag must be specified to delete">>);
     RevToDelete ->
-        couch_stats_collector:increment({httpd, document_deletes}),
+        % couch_stats_collector:increment({httpd, document_deletes}),
         {ok, NewRev} = couch_db:delete_doc(Db, DocId, [RevToDelete]),
         send_json(Req, 200, {[
             {ok, true},
@@ -394,7 +394,7 @@ db_doc_req(#httpd{method='GET'}=Req, Db, DocId) ->
         open_revs = Revs,
         options = Options
     } = parse_doc_query(Req),
-    couch_stats_collector:increment({httpd, document_reads}),
+    % couch_stats_collector:increment({httpd, document_reads}),
     case Revs of
     [] ->
         Doc = couch_doc_open(Db, DocId, Rev, Options),
@@ -471,10 +471,10 @@ db_doc_req(#httpd{method='PUT'}=Req, Db, DocId) ->
     end,
     case extract_header_rev(Req, ExplicitRev) of
     missing_rev ->
-        couch_stats_collector:increment({httpd, document_creates}),
+        % couch_stats_collector:increment({httpd, document_creates}),
         Revs = [];
     Rev ->
-        couch_stats_collector:increment({httpd, document_updates}),
+        % couch_stats_collector:increment({httpd, document_updates}),
         Revs = [Rev]
     end,
     {ok, NewRev} = couch_db:update_doc(Db, Doc#doc{id=DocId, revs=Revs}, Options),
@@ -498,7 +498,7 @@ db_doc_req(#httpd{method='COPY'}=Req, Db, SourceDocId) ->
 
     % save new doc
     {ok, NewTargetRev} = couch_db:update_doc(Db, Doc#doc{id=TargetDocId, revs=TargetRev}, []),
-    couch_stats_collector:increment({httpd, document_copies}),
+    % couch_stats_collector:increment({httpd, document_copies}),
 
     send_json(Req, 201, [{"Etag", "\"" ++ binary_to_list(NewTargetRev) ++ "\""}], {[
         {ok, true},
@@ -525,7 +525,7 @@ db_doc_req(#httpd{method='MOVE'}=Req, Db, SourceDocId) ->
         #doc{id=SourceDocId, revs=[SourceRev], deleted=true}
         ],
     {ok, ResultRevs} = couch_db:update_docs(Db, Docs, []),
-    couch_stats_collector:increment({httpd, document_moves}),
+    % couch_stats_collector:increment({httpd, document_moves}),
     
     DocResults = lists:zipwith(
         fun(FDoc, NewRev) ->
@@ -629,10 +629,10 @@ db_attachment_req(#httpd{method=Method}=Req, Db, DocId, FileNameParts)
 
     Doc = case extract_header_rev(Req, couch_httpd:qs_value(Req, "rev")) of
         missing_rev -> % make the new doc
-            couch_stats_collector:increment({httpd, document_creates}),
+            % couch_stats_collector:increment({httpd, document_creates}),
             #doc{id=DocId};
         Rev ->
-            couch_stats_collector:increment({httpd, document_updates}),
+            % couch_stats_collector:increment({httpd, document_updates}),
             case couch_db:open_doc_revs(Db, DocId, [Rev], []) of
             {ok, [{ok, Doc0}]}  -> Doc0#doc{revs=[Rev]};
             {ok, [Error]}       -> throw(Error)
diff --git a/src/couchdb/couch_stats.hrl b/src/couchdb/couch_stats.hrl
index 7b51aa0c..47a9a86f 100644
--- a/src/couchdb/couch_stats.hrl
+++ b/src/couchdb/couch_stats.hrl
@@ -11,11 +11,12 @@
 % the License.
 
 -record(aggregates, {
-    min=0,
-    max=0,
-    mean=0.0,
+    min = 0,
+    max = 0,
+    mean = 0.0,
     variance = 0.0,
-    stddev=0.0,
-    count=0,
-    last=0
+    stddev = 0.0,
+    count = 0,
+    last = 0,
+    description
 }).
diff --git a/src/couchdb/couch_stats_aggregator.erl b/src/couchdb/couch_stats_aggregator.erl
index 3d3db0ef..2a1e5797 100644
--- a/src/couchdb/couch_stats_aggregator.erl
+++ b/src/couchdb/couch_stats_aggregator.erl
@@ -23,7 +23,8 @@
          time_passed/0, clear_aggregates/1]).
 
 -record(state, {
-    aggregates = []
+    aggregates = [],
+    descriptions = []
 }).
 
 -define(COLLECTOR, couch_stats_collector).
@@ -61,6 +62,7 @@ all() ->
 init(_) ->
     ets:new(?MODULE, [named_table, set, protected]),
     init_timers(),
+    init_descriptions(),
     {ok, #state{}}.
 
 handle_call({get, Key}, _, State) ->
@@ -141,8 +143,8 @@ do_clear_aggregates(Time, #state{aggregates=Stats}) ->
     end, Stats),
     #state{aggregates=NewStats}.
 
-%% default Time is 0, which is when CouchDB started
 get_aggregate(Key, State) ->
+    %% default Time is 0, which is when CouchDB started
     get_aggregate(Key, State, '0').
 get_aggregate(Key, #state{aggregates=StatsList}, Time) ->
     Aggregates = case proplists:lookup(Key, StatsList) of
@@ -151,11 +153,17 @@ get_aggregate(Key, #state{aggregates=StatsList}, Time) ->
         {Key, Stats} ->
             case proplists:lookup(Time, Stats) of
                 none -> #aggregates{}; % empty record again
-                {Time, Stat} -> Stat
+                {Time, Stat} -> Stat#aggregates{description=get_description(Key)}
             end
     end,
     Aggregates.
 
+get_description(Key) ->
+    case ets:lookup(?MODULE, Key) of
+        [] -> <<"No description yet.">>;
+        [{_Key, Description}] -> Description
+    end.
+
 %% updates all aggregates for Key
 update_aggregates_loop(Key, Values, State, CounterType) ->
     #state{aggregates=AllStats} = State,
@@ -193,7 +201,9 @@ update_aggregates_loop(Key, Values, State, CounterType) ->
 
     % put the newly calculated aggregates into State and delete the previous
     % entry
-    #state{aggregates=[{Key, NewStats} | proplists:delete(Key, AllStats)]}.
+    #state{
+        aggregates=[{Key, NewStats} | proplists:delete(Key, AllStats)]
+    }.
 
 % does the actual updating of the aggregate record
 update_aggregates(Value, Stat, CounterType) ->
@@ -241,7 +251,7 @@ update_aggregates(Value, Stat, CounterType) ->
     end.
 
 
-aggregate_to_json_term(#aggregates{min=Min,max=Max,mean=Mean,stddev=Stddev,count=Count,last=Last}) ->
+aggregate_to_json_term(#aggregates{min=Min,max=Max,mean=Mean,stddev=Stddev,count=Count,last=Last,description=Description}) ->
     {[
         % current is redundant, but reads nicer in JSON
         {current, Last},
@@ -250,7 +260,8 @@ aggregate_to_json_term(#aggregates{min=Min,max=Max,mean=Mean,stddev=Stddev,count
         {min, Min},
         {max, Max},
         {stddev, Stddev},
-        {resolution, 1}
+        {resolution, 1},
+        {description, Description}
     ]}.
 
 get_stats(Key, State) ->
@@ -275,6 +286,49 @@ do_get_all(#state{aggregates=Stats}=State) ->
           {[{LastMod, {lists:sort(LastVals)}} | LastRestMods]}
     end.
 
+
+init_descriptions() ->
+
+    % ets is probably overkill here, but I didn't manage to keep the 
+    % descriptions in the gen_server state. Which means there is probably
+    % a bug in one of the handle_call() functions most likely the one that
+    % handles the time_passed message. But don't tell anyone, the math is
+    % correct :) -- Jan
+
+    % please keep this in alphabetical order
+    ets:insert(?MODULE, {{couchdb, database_changes}, <<"Number of times a database was changed">>}),
+    ets:insert(?MODULE, {{couchdb, database_reads}, <<"Number of times a document was read from a database">>}),
+    ets:insert(?MODULE, {{couchdb, open_databases}, <<"Number of open databases">>}),
+    ets:insert(?MODULE, {{couchdb, request_time}, <<"Length of a request inside CouchDB without Mochiweb">>}),
+
+    ets:insert(?MODULE, {{http_status_codes, '200'}, <<"Number of HTTP 200 OK responses">>}),
+    ets:insert(?MODULE, {{http_status_codes, '201'}, <<"Number of HTTP 201 Created responses">>}),
+    ets:insert(?MODULE, {{http_status_codes, '202'}, <<"Number of HTTP 202 Accepted responses">>}),
+    ets:insert(?MODULE, {{http_status_codes, '301'}, <<"Number of HTTP 301 Moved Permanently responses">>}),
+    ets:insert(?MODULE, {{http_status_codes, '304'}, <<"Number of HTTP 304 Not Modified responses">>}),
+    ets:insert(?MODULE, {{http_status_codes, '400'}, <<"Number of HTTP 400 Bad Request responses">>}),
+    ets:insert(?MODULE, {{http_status_codes, '401'}, <<"Number of HTTP 401 Unauthorized responses">>}),
+    ets:insert(?MODULE, {{http_status_codes, '403'}, <<"Number of HTTP 403 Forbidden responses">>}),
+    ets:insert(?MODULE, {{http_status_codes, '404'}, <<"Number of HTTP 404 Not Found responses">>}),
+    ets:insert(?MODULE, {{http_status_codes, '405'}, <<"Number of HTTP 405 Method Not Allowed responses">>}),
+    ets:insert(?MODULE, {{http_status_codes, '409'}, <<"Number of HTTP 409 Conflict responses">>}),
+    ets:insert(?MODULE, {{http_status_codes, '412'}, <<"Number of HTTP 412 Precondition Failed responses">>}),
+    ets:insert(?MODULE, {{http_status_codes, '500'}, <<"Number of HTTP 500 Internal Server Error responses">>}),
+
+    ets:insert(?MODULE, {{httpd, bulk_requests}, <<"Number of bulk requests">>}),
+    ets:insert(?MODULE, {{httpd, copy_requests}, <<"Number of HTTP COPY requests">>}),
+    ets:insert(?MODULE, {{httpd, delete_requests}, <<"Number of HTTP DELETE requests">>}),
+    ets:insert(?MODULE, {{httpd, get_requests}, <<"Number of HTTP GET requests">>}),
+    ets:insert(?MODULE, {{httpd, head_requests}, <<"Number of HTTP HEAD requests">>}),
+    ets:insert(?MODULE, {{httpd, move_requests}, <<"Number of HTTP MOVE requests">>}),
+    ets:insert(?MODULE, {{httpd, post_requests}, <<"Number of HTTP POST requests">>}),
+    ets:insert(?MODULE, {{httpd, requests}, <<"Number of HTTP requests">>}),
+    ets:insert(?MODULE, {{httpd, temporary_view_reads}, <<"Number of temporary view reads">>}),
+    ets:insert(?MODULE, {{httpd, view_reads}, <<"Number of view reads">>}),
+    ets:insert(?MODULE, {{httpd, put_requests}, <<"Number of HTTP PUT requests">>}).
+    % please keep this in alphabetical order
+
+
 % Timer
 
 init_timers() ->