From 8aab10d28cc675e6299a1d12d86e36db003b12db Mon Sep 17 00:00:00 2001
From: Alexey Shchepin <alexey@process-one.net>
Date: Sat, 12 May 2007 18:09:38 +0000
Subject: [PATCH] * src/ejabberd_auth.erl: Added
 get_vh_registered_users_number/1 function * src/ejabberd_auth_odbc.erl:
 Likewise * src/odbc/odbc_queries.erl: Added users_number/1 function *
 src/ejabberd.cfg.example: Added an example for pgsql_users_number_estimate
 option

SVN Revision: 766
---
 ChangeLog                  |  7 +++++++
 src/ejabberd.cfg.example   |  4 ++++
 src/ejabberd_auth.erl      | 14 ++++++++++++++
 src/ejabberd_auth_odbc.erl | 12 ++++++++++--
 src/odbc/odbc_queries.erl  | 15 +++++++++++++++
 5 files changed, 50 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index eca44b631..216974af4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,12 @@
 2007-05-12  Alexey Shchepin  <alexey@sevcom.net>
 
+	* src/ejabberd_auth.erl: Added get_vh_registered_users_number/1
+	function
+	* src/ejabberd_auth_odbc.erl: Likewise
+	* src/odbc/odbc_queries.erl: Added users_number/1 function
+	* src/ejabberd.cfg.example: Added an example for
+	pgsql_users_number_estimate option
+
 	* src/ejabberd_auth_anonymous.erl: Added anonymous_purge_hook
 	(thanks to Christophe Romain and Mickael Remond)
 	* src/mod_offline.erl: Likewise
diff --git a/src/ejabberd.cfg.example b/src/ejabberd.cfg.example
index 654313355..00581047b 100644
--- a/src/ejabberd.cfg.example
+++ b/src/ejabberd.cfg.example
@@ -96,6 +96,10 @@
 %{auth_method, odbc}.
 %{odbc_server, "DSN=ejabberd;UID=ejabberd;PWD=ejabberd"}.
 
+% Uncomment this if you are using postgres, having a large DB, and need a
+% faster but inexact replacement for "select count(*) from users"
+%{pgsql_users_number_estimate, true}.
+
 
 % Host name:
 {hosts, ["localhost"]}.
diff --git a/src/ejabberd_auth.erl b/src/ejabberd_auth.erl
index 4c34ae76a..6ecd054d1 100644
--- a/src/ejabberd_auth.erl
+++ b/src/ejabberd_auth.erl
@@ -22,6 +22,7 @@
 	 try_register/3,
 	 dirty_get_registered_users/0,
 	 get_vh_registered_users/1,
+	 get_vh_registered_users_number/1,
 	 get_password/2,
 	 get_password_s/2,
 	 is_user_exists/2,
@@ -107,6 +108,19 @@ get_vh_registered_users(Server) ->
 	      M:get_vh_registered_users(Server)
       end, auth_modules(Server)).
 
+get_vh_registered_users_number(Server) ->
+    lists:sum(
+      lists:map(
+	fun(M) ->
+		case erlang:function_exported(
+		       M, get_vh_registered_users_number, 1) of
+		    true ->
+			M:get_vh_registered_users_number(Server);
+		    false ->
+			length(M:get_vh_registered_users(Server))
+		end
+	end, auth_modules(Server))).
+
 get_password(User, Server) ->
     lists:foldl(
       fun(M, false) ->
diff --git a/src/ejabberd_auth_odbc.erl b/src/ejabberd_auth_odbc.erl
index 60fce6d79..909a5d7a1 100644
--- a/src/ejabberd_auth_odbc.erl
+++ b/src/ejabberd_auth_odbc.erl
@@ -18,6 +18,7 @@
 	 try_register/3,
 	 dirty_get_registered_users/0,
 	 get_vh_registered_users/1,
+	 get_vh_registered_users_number/1,
 	 get_password/2,
 	 get_password_s/2,
 	 is_user_exists/2,
@@ -28,8 +29,6 @@
 
 -include("ejabberd.hrl").
 
--record(passwd, {user, password}).
-
 %%%----------------------------------------------------------------------
 %%% API
 %%%----------------------------------------------------------------------
@@ -123,6 +122,15 @@ get_vh_registered_users(Server) ->
 	    []
     end.
 
+get_vh_registered_users_number(Server) ->
+    LServer = jlib:nameprep(Server),
+    case catch odbc_queries:users_number(LServer) of
+	{selected, [_], [{Res}]} ->
+	    list_to_integer(Res);
+	_ ->
+	    0
+    end.
+
 get_password(User, Server) ->
     case jlib:nodeprep(User) of
 	error ->
diff --git a/src/odbc/odbc_queries.erl b/src/odbc/odbc_queries.erl
index f42a62a80..614e1d6ec 100644
--- a/src/odbc/odbc_queries.erl
+++ b/src/odbc/odbc_queries.erl
@@ -15,6 +15,7 @@
 	 del_user/2,
 	 del_user_return_password/3,
 	 list_users/1,
+	 users_number/1,
 	 add_spool_sql/2,
 	 add_spool/2,
 	 get_and_del_spool_msg_t/2,
@@ -109,6 +110,20 @@ list_users(LServer) ->
       LServer,
       "select username from users").
 
+users_number(LServer) ->
+    case ejabberd_config:get_local_option(
+	   {pgsql_users_number_estimate, LServer}) of
+	true ->
+	    ejabberd_odbc:sql_query(
+	      LServer,
+	      "select reltuples from pg_class "
+	      "where oid = 'users'::regclass::oid");
+	_ ->
+	    ejabberd_odbc:sql_query(
+	      LServer,
+	      "select count(*) from users")
+    end.
+
 add_spool_sql(Username, XML) ->
     ["insert into spool(username, xml) "
      "values ('", Username, "', '",