iilyak commented on a change in pull request #1370: [5/5] Clustered Purge
Implementation
URL: https://github.com/apache/couchdb/pull/1370#discussion_r196612907
##########
File path: src/couch/src/couch_db.erl
##########
@@ -369,8 +379,153 @@ get_full_doc_info(Db, Id) ->
get_full_doc_infos(Db, Ids) ->
couch_db_engine:open_docs(Db, Ids).
-purge_docs(#db{main_pid=Pid}, IdsRevs) ->
- gen_server:call(Pid, {purge_docs, IdsRevs}).
+purge_docs(Db, IdRevs) ->
+ purge_docs(Db, IdRevs, []).
+
+-spec purge_docs(#db{}, [{UUId, Id, [Rev]}], [PurgeOption]) ->
+ {ok, [Reply]} when
+ UUId :: binary(),
+ Id :: binary(),
+ Rev :: {non_neg_integer(), binary()},
+ PurgeOption :: interactive_edit | replicated_changes,
+ Reply :: {ok, []} | {ok, [Rev]}.
+purge_docs(#db{main_pid = Pid} = Db, UUIDsIdsRevs, Options) ->
+ % Check here if any UUIDs already exist when
+ % we're not replicating purge infos
+ IsRepl = lists:member(replicated_changes, Options),
+ if IsRepl -> ok; true ->
+ UUIDs = [UUID || {UUID, _, _} <- UUIDsIdsRevs],
+ lists:foreach(fun(Resp) ->
+ if Resp == not_found -> ok; true ->
+ Fmt = "Duplicate purge info UIUD: ~s",
+ Reason = io_lib:format(Fmt, [element(2, Resp)]),
+ throw({badreq, Reason})
+ end
+ end, get_purge_infos(Db, UUIDs))
+ end,
+ increment_stat(Db, [couchdb, database_purges]),
+ gen_server:call(Pid, {purge_docs, UUIDsIdsRevs, Options}).
+
+-spec get_purge_infos(#db{}, [UUId]) -> [PurgeInfo] when
+ UUId :: binary(),
+ PurgeInfo :: {PurgeSeq, UUId, Id, [Rev]} | not_found,
+ PurgeSeq :: non_neg_integer(),
+ Id :: binary(),
+ Rev :: {non_neg_integer(), binary()}.
+get_purge_infos(Db, UUIDs) ->
+ couch_db_engine:load_purge_infos(Db, UUIDs).
+
+
+get_minimum_purge_seq(#db{} = Db) ->
+ PurgeSeq = couch_db_engine:get_purge_seq(Db),
+ OldestPurgeSeq = couch_db_engine:get_oldest_purge_seq(Db),
+ PurgeInfosLimit = couch_db_engine:get_purge_infos_limit(Db),
+
+ FoldFun = fun(#doc{id = DocId, body = {Props}}, SeqAcc) ->
+ case DocId of
+ <<?LOCAL_DOC_PREFIX, "purge-", _/binary>> ->
+ ClientSeq = couch_util:get_value(<<"purge_seq">>, Props),
+ case ClientSeq of
+ CS when is_integer(CS), CS >= PurgeSeq - PurgeInfosLimit ->
+ {ok, SeqAcc};
+ CS when is_integer(CS) ->
+ case purge_client_exists(Db, DocId, Props) of
+ true -> {ok, erlang:min(CS, SeqAcc)};
+ false -> {ok, SeqAcc}
+ end;
+ _ ->
+ % If there's a broken doc we have to keep every
+ % purge info until the doc is fixed or removed.
+ Fmt = "Invalid purge doc '~s' with purge_seq '~w'",
+ couch_log:error(Fmt, [DocId, ClientSeq]),
+ {ok, erlang:min(OldestPurgeSeq, SeqAcc)}
+ end;
+ _ ->
+ {stop, SeqAcc}
+ end
+ end,
+ InitMinSeq = PurgeSeq - PurgeInfosLimit,
+ Opts = [
+ {start_key, list_to_binary(?LOCAL_DOC_PREFIX ++ "purge-")}
+ ],
+ {ok, MinIdxSeq} = couch_db:fold_local_docs(Db, FoldFun, InitMinSeq, Opts),
+ FinalSeq = case MinIdxSeq < PurgeSeq - PurgeInfosLimit of
+ true -> MinIdxSeq;
+ false -> erlang:max(0, PurgeSeq - PurgeInfosLimit)
+ end,
+ % Log a warning if we've got a purge sequence exceeding the
+ % configured threshold.
+ if FinalSeq >= (PurgeSeq - PurgeInfosLimit) -> ok; true ->
+ Fmt = "The purge sequence for '~s' exceeds configured threshold",
+ couch_log:warning(Fmt, [couch_db:name(Db)])
+ end,
+ FinalSeq.
+
+
+purge_client_exists(DbName, DocId, Props) ->
+ % Warn about clients that have not updated their purge
+ % checkpoints in the last "index_lag_warn_seconds"
+ LagWindow = config:get_integer(
+ "purge", "index_lag_warn_seconds", 86400), % Default 24 hours
+
+ {Mega, Secs, _} = os:timestamp(),
+ NowSecs = Mega * 1000000 + Secs,
+ LagThreshold = NowSecs - LagWindow,
+
+ try
+ CheckFun = get_purge_client_fun(DocId, Props),
+ Exists = CheckFun(DbName, DocId, Props),
Review comment:
I don't quite understand it. We are calling a function with arity 3 here.
- `get_purge_client_fun/2` returns the function with arity 2 [see
here](https://github.com/apache/couchdb/pull/1370/files#diff-66129b4f374c3cde3fc9a49fa8a9452eR509).
- mem3_rep:verify_purge_checkpoint has arity 3
- couch_mrview_index:verify_index_exists has arity 1
I am sure I missing something.
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
[email protected]
With regards,
Apache Git Services
