## 1.104. subscribeset_int( integer, integer, integer, boolean )

Function Properties
Language: PLPGSQL
Return Type: integer

subscribeSet_int (sub_set, sub_provider, sub_receiver, sub_forward) Internal actions for subscribing receiver sub_receiver to subscription set sub_set.

    declare
    	p_sub_set			alias for $1;
    	p_sub_provider		alias for $2;
    	p_sub_receiver		alias for $3;
    	p_sub_forward		alias for $4;
    	v_set_origin		int4;
    	v_sub_row			record;
    begin
    	-- ----
    	-- Grab the central configuration lock
    	-- ----
    	lock table sl_config_lock;

    	-- ----
    	-- Provider change is only allowed for active sets
    	-- ----
    	if p_sub_receiver = getLocalNodeId('_schemadoc') then
    		select sub_active into v_sub_row from sl_subscribe
    				where sub_set = p_sub_set
    				and sub_receiver = p_sub_receiver;
    		if found then
    			if not v_sub_row.sub_active then
    				raise exception 'Slony-I: set % is not active, cannot change provider',
    						p_sub_set;
    			end if;
    		end if;
    	end if;

    	-- ----
    	-- Try to change provider and/or forward for an existing subscription
    	-- ----
    	update sl_subscribe
    			set sub_provider = p_sub_provider,
    				sub_forward = p_sub_forward
    			where sub_set = p_sub_set
    			and sub_receiver = p_sub_receiver;
    	if found then
    		return p_sub_set;
    	end if;

    	-- ----
    	-- Not found, insert a new one
    	-- ----
    	if not exists (select true from sl_path
    			where pa_server = p_sub_provider
    			and pa_client = p_sub_receiver)
    	then
    		insert into sl_path
    				(pa_server, pa_client, pa_conninfo, pa_connretry)
    				values
    				(p_sub_provider, p_sub_receiver,
    				'<event pending>', 10);
    	end if;
    	insert into sl_subscribe
    			(sub_set, sub_provider, sub_receiver, sub_forward, sub_active)
    			values (p_sub_set, p_sub_provider, p_sub_receiver,
    				p_sub_forward, false);

    	-- ----
    	-- If the set origin is here, then enable the subscription
    	-- ----
    	select set_origin into v_set_origin
    			from sl_set
    			where set_id = p_sub_set;
    	if not found then
    		raise exception 'Slony-I: set % not found', p_sub_set;
    	end if;

    	if v_set_origin = getLocalNodeId('_schemadoc') then
    		perform createEvent('_schemadoc', 'ENABLE_SUBSCRIPTION',
    				p_sub_set, p_sub_provider, p_sub_receiver,
    				case p_sub_forward when true then 't' else 'f' end);
    		perform enableSubscription(p_sub_set,
    				p_sub_provider, p_sub_receiver);
    	end if;

    	-- Rewrite sl_listen table
    	perform RebuildListenEntries();

    	return p_sub_set;
    end;