Get a new lb pid if existing pid is not alive
It's possible for the connection process associated with a pid in the
ibrowse_lb ets table to die, yet remain in the table, in which case
subsequent requests to the corresponding {Host, Port} will result in an
error like the following:
(node1@127.0.0.1)9> ibrowse:send_req("http://localhost:15984", [], get).
** exception exit: {noproc,
{gen_server,call,
[<0.2451.0>,
{spawn_connection,
{url,"http://localhost:15984","localhost",15984,
undefined,undefined,"/",http,hostname},
10,10,
{[],false},
[]}]}}
in function gen_server:call/2 (gen_server.erl, line 215)
in call from ibrowse:try_routing_request/14 (src/ibrowse.erl, line 377)
This checks whether the pid about to be returned from the table is alive,
and if not, the entry is deleted, and a new pid is obtained.
diff --git a/src/ibrowse.erl b/src/ibrowse.erl
index 2066799..5adf047 100644
--- a/src/ibrowse.erl
+++ b/src/ibrowse.erl
@@ -342,12 +342,7 @@
#url{host = Host,
port = Port,
protocol = Protocol} = Parsed_url ->
- Lb_pid = case ets:lookup(ibrowse_lb, {Host, Port}) of
- [] ->
- get_lb_pid(Parsed_url);
- [#lb_pid{pid = Lb_pid_1}] ->
- Lb_pid_1
- end,
+ Lb_pid = lb_pid(Host, Port, Parsed_url),
Max_sessions = get_max_sessions(Host, Port, Options),
Max_pipeline_size = get_max_pipeline_size(Host, Port, Options),
Max_attempts = get_max_attempts(Host, Port, Options),
@@ -367,6 +362,20 @@
{error, {url_parsing_failed, Err}}
end.
+lb_pid(Host, Port, Url) ->
+ case ets:lookup(ibrowse_lb, {Host, Port}) of
+ [] ->
+ get_lb_pid(Url);
+ [#lb_pid{pid = Pid}] ->
+ case is_process_alive(Pid) of
+ true ->
+ Pid;
+ false ->
+ ets:delete(ibrowse_lb, {Host, Port}),
+ get_lb_pid(Url)
+ end
+ end.
+
try_routing_request(Lb_pid, Parsed_url,
Max_sessions,
Max_pipeline_size,
diff --git a/test/ibrowse_test.erl b/test/ibrowse_test.erl
index cd78049..fc2e4af 100644
--- a/test/ibrowse_test.erl
+++ b/test/ibrowse_test.erl
@@ -40,7 +40,8 @@
test_save_to_file_no_content_length/0,
socks5_noauth/0,
socks5_auth_succ/0,
- socks5_auth_fail/0
+ socks5_auth_fail/0,
+ test_dead_lb_pid/0
]).
-include_lib("ibrowse/include/ibrowse.hrl").
@@ -64,7 +65,8 @@
{local_test_fun, test_retry_of_requests, []},
{local_test_fun, verify_chunked_streaming, []},
{local_test_fun, test_chunked_streaming_once, []},
- {local_test_fun, test_generate_body_0, []}
+ {local_test_fun, test_generate_body_0, []},
+ {local_test_fun, test_dead_lb_pid, []}
]).
-define(TEST_LIST, [{"http://intranet/messenger", get},
@@ -877,6 +879,22 @@
ets:delete(Tid)
end.
+%% Test that when an lb process dies, its entry is removed from the ibrowse_lb
+%% table by the next requestor and replaced with a new process
+%%------------------------------------------------------------------------------
+test_dead_lb_pid() ->
+ {Host, Port} = {"localhost", 8181},
+ Url = "http://" ++ Host ++ ":" ++ integer_to_list(Port),
+ {ok, "200", _, _} = ibrowse:send_req(Url, [], get),
+ [{lb_pid, {Host, Port}, Pid}] = ets:lookup(ibrowse_lb, {Host, Port}),
+ true = exit(Pid, kill),
+ false = is_process_alive(Pid),
+ {ok, "200", _, _} = ibrowse:send_req(Url, [], get),
+ [{lb_pid, {Host, Port}, NewPid}] = ets:lookup(ibrowse_lb, {Host, Port}),
+ true = NewPid /= Pid,
+ true = is_process_alive(NewPid),
+ success.
+
do_trace(Fmt, Args) ->
do_trace(get(my_trace_flag), Fmt, Args).
