Allow agent checks to obtain information in
an HTTP header of the response to an http check.
Signed-off-by: Simon Horman <ho...@verge.net.au>
---
v4
* Do not duplicate code that is in process_result()
v2 - v3
* No change
---
doc/configuration.txt | 24 ++++++++++++--
include/types/proxy.h | 2 ++
src/cfgparse.c | 20 +++++++++++-
src/checks.c | 85 +++++++++++++++++++++++++++++++++++--------------
4 files changed, 104 insertions(+), 27 deletions(-)
diff --git a/doc/configuration.txt b/doc/configuration.txt
index acb356d..19dc7db 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -1139,6 +1139,7 @@ force-persist - X
X X
fullconn X - X X
grace X X X X
hash-type X - X X
+http-check agent-hdr X - X X
http-check disable-on-404 X - X X
http-check expect - - X X
http-check send-state X - X X
@@ -2527,6 +2528,24 @@ hash-type <method>
See also : "balance", "server"
+http-check agent-hdr
+ Use the value of the given http header as the result of an agent check
+ May be used in sections : defaults | frontend | listen | backend
+ yes | no | yes | yes
+ Arguments :
+
+ <header> The header string to use to send the server name
+
+ When this option is set an http check is enhanced to read the value
+ of the given header in the response to an http check and interpret
+ it as the result of an agent check. In this way an http and agent check
+ may be performed simultaneously.
+
+ This option is overridden by the agent-port parameter.
+
+ See also : "option lb-agent-chk", "agent-port"
+
+
http-check disable-on-404
Enable a maintenance mode upon HTTP/404 response to health-checks
May be used in sections : defaults | frontend | listen | backend
@@ -7682,10 +7701,11 @@ agent-port <port>
In this the agent check is run in conjunction with another check
and as such the check backend should be set to some value other than
- "lb-agent-check". An alternative scenario is to run only an agent check
+ "lb-agent-check". A second scenario is to run only an agent check
in which case the check backend should be set to "lb-agent-check" and
"agent-port" should not be set; in that scenario the port may be set
- using the "port" parameter.
+ using the "port" parameter. A third scenario is to use "http-check
+ agent-hdr" to run an agent and http checks simultaneously over HTTP.
See also the "agent-inter" parameter.
diff --git a/include/types/proxy.h b/include/types/proxy.h
index e6bc755..66e5db7 100644
--- a/include/types/proxy.h
+++ b/include/types/proxy.h
@@ -328,6 +328,7 @@ struct proxy {
int check_len; /* Length of the HTTP or SSL3
request */
char *expect_str; /* http-check expected content
: string or text version of the regex */
regex_t *expect_regex; /* http-check expected content
*/
+ const char *agent_http_header; /* http-check header to use for
agent checks */
struct chunk errmsg[HTTP_ERR_SIZE]; /* default or customized error
messages for known errors */
int uuid; /* universally unique proxy ID,
used for SNMP */
unsigned int backlog; /* force the frontend's listen
backlog */
@@ -359,6 +360,7 @@ struct proxy {
} conf; /* config information */
void *parent; /* parent of the proxy when
applicable */
struct comp *comp; /* http compression */
+
};
struct switching_rule {
diff --git a/src/cfgparse.c b/src/cfgparse.c
index ab309cf..23bbf2b 100644
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -3867,7 +3867,25 @@ stats_error_parsing:
if (warnifnotcap(curproxy, PR_CAP_BE, file, linenum, args[0],
NULL))
err_code |= ERR_WARN;
- if (strcmp(args[1], "disable-on-404") == 0) {
+ if (strcmp(args[1], "agent-hdr") == 0) {
+ int cur_arg;
+
+ if (curproxy->agent_http_header) {
+ Alert("parsing [%s:%d] : '%s %s' already
specified.\n", file, linenum, args[0], args[1]);
+ err_code |= ERR_ALERT | ERR_FATAL;
+ goto out;
+ }
+
+ cur_arg = 2;
+ if (!*(args[cur_arg ])) {
+ Alert("parsing [%s:%d] : '%s %s' expects
<string> as an argument.\n",
+ file, linenum, args[0], args[1]);
+ err_code |= ERR_ALERT | ERR_FATAL;
+ goto out;
+ }
+ curproxy->agent_http_header = strdup(args[cur_arg]);
+ }
+ else if (strcmp(args[1], "disable-on-404") == 0) {
/* enable a graceful server shutdown on an HTTP 404
response */
curproxy->options |= PR_O_DISABLE404;
}
diff --git a/src/checks.c b/src/checks.c
index 249a6ee..5d893f8 100644
--- a/src/checks.c
+++ b/src/checks.c
@@ -1306,6 +1306,35 @@ static struct task *server_warmup(struct task *t)
return t;
}
+static void process_result(struct check *check)
+{
+ struct server *s = check->server;
+
+ if (check->result & SRV_CHK_FAILED) { /* a failure or timeout
detected */
+ if (check->health > s->rise) {
+ check->health--; /* still good */
+ s->counters.failed_checks++;
+ }
+ else
+ set_server_down(check);
+ }
+ else { /* check was OK */
+ /* we may have to add/remove this server from the LB group */
+ if ((s->state & SRV_RUNNING) && (s->proxy->options &
PR_O_DISABLE404)) {
+ if ((s->state & SRV_GOINGDOWN) && !(check->result &
SRV_CHK_DISABLE))
+ set_server_enabled(s);
+ else if (!(s->state & SRV_GOINGDOWN) && (check->result
& SRV_CHK_DISABLE))
+ set_server_disabled(check);
+ }
+
+ if (check->health < s->rise + s->fall - 1) {
+ check->health++; /* was bad, stays for a while */
+ set_server_up(check);
+ }
+ }
+ check->state &= ~CHK_RUNNING;
+}
+
/*
* manages a server health-check. Returns
* the time the task accepts to wait, or TIME_ETERNITY for infinity.
@@ -1502,29 +1531,17 @@ static struct task *process_chk(struct task *t)
conn_full_close(conn);
}
- if (check->result & SRV_CHK_FAILED) { /* a failure or
timeout detected */
- if (check->health > s->rise) {
- check->health--; /* still good */
- s->counters.failed_checks++;
- }
- else
- set_server_down(check);
- }
- else { /* check was OK */
- /* we may have to add/remove this server from the LB
group */
- if ((s->state & SRV_RUNNING) && (s->proxy->options &
PR_O_DISABLE404)) {
- if ((s->state & SRV_GOINGDOWN) &&
!(check->result & SRV_CHK_DISABLE))
- set_server_enabled(s);
- else if (!(s->state & SRV_GOINGDOWN) &&
(check->result & SRV_CHK_DISABLE))
- set_server_disabled(check);
- }
+ process_result(check);
- if (check->health < s->rise + s->fall - 1) {
- check->health++; /* was bad, stays for a while
*/
- set_server_up(check);
- }
+ /* The agent check may run without a task if
+ * it is performed as aprt of the primary health check.
+ * If so process its result, here, while processing
+ * the primary health check.
+ */
+ if (!check->server->agent.task &&
+ check->server->agent.state != HCHK_STATUS_INI) {
+ process_result(&check->server->agent);
}
- check->state &= ~CHK_RUNNING;
rv = 0;
if (global.spread_checks > 0) {
@@ -1716,9 +1733,22 @@ static int httpchk_expect(struct server *s, int done)
{
static char status_msg[] = "HTTP status check returned code <000>";
char status_code[] = "000";
- char *contentptr;
+ char *contentptr = NULL, *agent_value = NULL;
int ret;
+ if (s->proxy->agent_http_header) {
+ httpchk_parse_header(s, s->proxy->agent_http_header,
&agent_value);
+
+ if (!agent_value || !strchr(agent_value, '\n')) {
+ /* if we don't match, we may need to wait more */
+ if (!done)
+ return 0;
+ set_server_check_status(&s->agent, HCHK_STATUS_L7RSP,
+ "HTTP check did not match
agent-hdr");
+ agent_value = NULL;
+ }
+ }
+
switch (s->proxy->options2 & PR_O2_EXP_TYPE) {
case PR_O2_EXP_STS:
case PR_O2_EXP_RSTS:
@@ -1739,7 +1769,8 @@ static int httpchk_expect(struct server *s, int done)
case PR_O2_EXP_STR:
case PR_O2_EXP_RSTR:
- contentptr = httpchk_parse_header(s, NULL, NULL);
+ if (!contentptr)
+ contentptr = httpchk_parse_header(s,
s->proxy->agent_http_header, &agent_value);
/* Check that response contains a body... */
if (*contentptr == '\0') {
@@ -1747,7 +1778,7 @@ static int httpchk_expect(struct server *s, int done)
return 0;
set_server_check_status(&s->check, HCHK_STATUS_L7RSP,
"HTTP content check could not find a response body or an empty response body
was found");
- return 1;
+ goto agent;
}
/* Check the response content against the supplied string
@@ -1780,6 +1811,12 @@ static int httpchk_expect(struct server *s, int done)
}
break;
}
+
+agent:
+ if (s->proxy->agent_http_header && agent_value) {
+ agent_expect(&s->agent, agent_value);
+ }
+
return 1;
}
--
1.7.10.4
