MINOR: stream: Add be_max_retries/cur_max_retries sample fetch functions

These new samples can be used to get, resepectively, the backend value for
the maximum connection retries and the current value applied to the stream.
They could be used to know if a "set-retries" action was performed.

A dedicated reg-test was also added.

doc/configuration.txt

@@ -24325,6 +24325,7 @@ bc_srv_queue                                       integer
 be_id                                              integer
 be_name                                            string
 be_connect_timeout                                 integer
+be_max_retries                                     integer
 be_queue_timeout                                   integer
 be_server_timeout                                  integer
 be_tarpit_timeout                                  integer
@@ -24333,6 +24334,7 @@ bytes_in                                           integer
 bytes_out                                          integer
 cur_connect_timeout                                integer
 cur_client_timeout                                 integer
+cur_max_retries                                    integer
 cur_queue_timeout                                  integer
 cur_server_timeout                                 integer
 cur_tarpit_timeout                                 integer
@@ -24669,6 +24671,11 @@ be_connect_timeout : integer
   current backend. This timeout can be overwritten by a "set-timeout" rule. See
   also the "cur_connect_timeout".
 
+be_max_retries : integer
+  Returns the configuration value for the connection retries of the current
+  backend. This value can be overwritten by a "set-retries" rule. See also the
+  "cur_max_retries".
+
 be_name : string
   Returns a string containing the current backend's name. It can be used in
   frontends with responses to check which backend processed the request. If
@@ -24712,6 +24719,11 @@ cur_client_timeout : integer
   In the default case, this will be equal to fe_client_timeout unless a
   "set-timeout" rule has been applied. See also "fe_client_timeout".
 
+cur_max_retries : integer
+  Returns the currently applied connect retries for the stream.
+  In the default case, this will be equal to be_max_retries unless a
+  "set-retries" rule has been applied. See also "be_max_retries".
+
 cur_queue_timeout : integer
   Returns the currently applied queue timeout in millisecond for the stream.
   In the default case, this will be equal to be_queue_timeout unless a

reg-tests/stream/set-retries.vtc

@@ -0,0 +1,114 @@
+varnishtest "set-retries action test"
+
+feature ignore_unknown_macro
+
+server srv_h1 -repeat 6 {
+    rxreq
+    txresp -hdr "Connection: close"
+} -start
+
+
+haproxy hap -conf {
+    global
+    .if feature(THREAD)
+        thread-groups 1
+    .endif
+
+    defaults
+        timeout connect 5s
+        timeout client 5s
+        timeout server 5s
+	retries 3
+        log global
+
+    listen li1
+        mode http
+        bind "fd@${li1}"
+        http-after-response set-header retries "%[be_max_retries] %[cur_max_retries]"
+        server srv_h1 ${srv_h1_addr}:${srv_h1_port}
+
+    listen li2
+        mode http
+        bind "fd@${li2}"
+        http-request set-retries 5
+        http-after-response set-header retries "%[be_max_retries] %[cur_max_retries]"
+        server srv_h1 ${srv_h1_addr}:${srv_h1_port}
+
+    listen li3
+        mode http
+        bind "fd@${li3}"
+        http-request set-retries 5
+        http-after-response set-header retries "%[be_max_retries] %[cur_max_retries]"
+	default_backend be1
+
+    listen li4
+        mode http
+        bind "fd@${li4}"
+        http-request set-retries 4
+        http-after-response set-header retries "%[be_max_retries] %[cur_max_retries]"
+	default_backend be2
+
+    frontend fe5
+        mode http
+        bind "fd@${fe5}"
+        http-after-response set-header retries "%[be_max_retries] %[cur_max_retries]"
+        default_backend be1
+
+    frontend fe6
+        mode http
+        bind "fd@${fe6}"
+        http-after-response set-header retries "%[be_max_retries] %[cur_max_retries]"
+        default_backend be2
+
+    backend be1
+       mode http
+       server srv_h1 ${srv_h1_addr}:${srv_h1_port}
+
+    backend be2
+       mode http
+       http-request set-retries 5
+       server srv_h1 ${srv_h1_addr}:${srv_h1_port}
+
+} -start
+
+client c1 -connect ${hap_li1_sock} {
+    txreq
+    rxresp
+    expect resp.status == 200
+    expect resp.http.retries == "3 3"
+} -run
+
+client c2 -connect ${hap_li2_sock} {
+    txreq
+    rxresp
+    expect resp.status == 200
+    expect resp.http.retries == "3 5"
+} -run
+
+client c3 -connect ${hap_li3_sock} {
+    txreq
+    rxresp
+    expect resp.status == 200
+    expect resp.http.retries == "3 3"
+} -run
+
+client c4 -connect ${hap_li4_sock} {
+    txreq
+    rxresp
+    expect resp.status == 200
+    expect resp.http.retries == "3 5"
+} -run
+
+client c5 -connect ${hap_fe5_sock} {
+    txreq
+    rxresp
+    expect resp.status == 200
+    expect resp.http.retries == "3 3"
+} -run
+
+client c6 -connect ${hap_fe6_sock} {
+    txreq
+    rxresp
+    expect resp.status == 200
+    expect resp.http.retries == "3 5"
+} -run

src/backend.c

@@ -3756,6 +3756,24 @@ smp_fetch_srv_uweight(const struct arg *args, struct sample *smp, const char *kw
 	return 1;
 }
 
+static int
+smp_fetch_be_max_retries(const struct arg *args, struct sample *smp, const char *km, void *private)
+{
+	struct proxy *px = NULL;
+
+	if (smp->strm)
+		px = smp->strm->be;
+	else if (obj_type(smp->sess->origin) == OBJ_TYPE_CHECK)
+		px = __objt_check(smp->sess->origin)->proxy;
+	if (!px)
+		return 0;
+
+	smp->flags = SMP_F_VOL_TXN;
+	smp->data.type = SMP_T_SINT;
+	smp->data.u.sint = px->conn_retries;
+	return 1;
+}
+
 static int
 smp_fetch_be_connect_timeout(const struct arg *args, struct sample *smp, const char *km, void *private)
 {
@@ -3929,6 +3947,7 @@ static struct sample_fetch_kw_list smp_kws = {ILH, {
 	{ "be_id",             smp_fetch_be_id,             0,           NULL, SMP_T_SINT, SMP_USE_BKEND, },
 	{ "be_name",           smp_fetch_be_name,           0,           NULL, SMP_T_STR,  SMP_USE_BKEND, },
 	{ "be_connect_timeout",smp_fetch_be_connect_timeout,0,           NULL, SMP_T_SINT, SMP_USE_BKEND, },
+	{ "be_max_retries",    smp_fetch_be_max_retries,    0,           NULL, SMP_T_SINT, SMP_USE_BKEND, },
 	{ "be_queue_timeout",  smp_fetch_be_queue_timeout,  0,           NULL, SMP_T_SINT, SMP_USE_BKEND, },
 	{ "be_server_timeout", smp_fetch_be_server_timeout, 0,           NULL, SMP_T_SINT, SMP_USE_BKEND, },
 	{ "be_sess_rate",      smp_fetch_be_sess_rate,      ARG1(1,BE),  NULL, SMP_T_SINT, SMP_USE_INTRN, },

src/stream.c

@@ -4420,6 +4420,17 @@ static struct action_kw_list stream_http_after_res_actions =  { ILH, {
 
 INITCALL1(STG_REGISTER, http_after_res_keywords_register, &stream_http_after_res_actions);
 
+static int smp_fetch_cur_max_retries(const struct arg *args, struct sample *smp, const char *km, void *private)
+{
+	smp->flags = SMP_F_VOL_TXN;
+	smp->data.type = SMP_T_SINT;
+	if (!smp->strm)
+		return 0;
+
+	smp->data.u.sint = smp->strm->max_retries;
+	return 1;
+}
+
 static int smp_fetch_cur_connect_timeout(const struct arg *args, struct sample *smp, const char *km, void *private)
 {
 	smp->flags = SMP_F_VOL_TXN;
@@ -4687,6 +4698,7 @@ static int smp_fetch_redispatched(const struct arg *args, struct sample *smp, co
 static struct sample_fetch_kw_list smp_kws = {ILH, {
 	{ "cur_connect_timeout",smp_fetch_cur_connect_timeout,0, NULL, SMP_T_SINT, SMP_USE_BKEND, },
 	{ "cur_client_timeout", smp_fetch_cur_client_timeout, 0, NULL, SMP_T_SINT, SMP_USE_FTEND, },
+	{ "cur_max_retries",    smp_fetch_cur_max_retries,    0, NULL, SMP_T_SINT, SMP_USE_BKEND, },
 	{ "cur_server_timeout", smp_fetch_cur_server_timeout, 0, NULL, SMP_T_SINT, SMP_USE_BKEND, },
 	{ "cur_queue_timeout",  smp_fetch_cur_queue_timeout,  0, NULL, SMP_T_SINT, SMP_USE_BKEND, },
 	{ "cur_tarpit_timeout", smp_fetch_cur_tarpit_timeout, 0, NULL, SMP_T_SINT, SMP_USE_FTEND | SMP_USE_BKEND, },