[MEDIUM] checks: add support for HTTP contents lookup
This patch adds the "http-check expect [r]{string,status}" statements
which enable health checks based on whether the response status or body
to an HTTP request contains a string or matches a regex.
This probably is one of the oldest patches that remained unmerged. Over
the time, several people have contributed to it, among which FinalBSD
(first and second implementations), Nick Chalk (port to 1.4), Anze
Skerlavaj (tests and fixes), Cyril Bonté (general fixes), and of course
myself for the final fixes and doc during integration.
Some people already use an old version of this patch which has several
issues, among which the inability to search for a plain string that is
not at the beginning of the data, and the inability to look for response
contents that are provided in a second and subsequent recv() calls. But
since some configs are already deployed, it was quite important to ensure
a 100% compatible behaviour on the working cases.
Thus, that patch fixes the issues while maintaining config compatibility
with already deployed versions.
(cherry picked from commit b507c43a3ce9a8e8e4b770e52e4edc20cba4c37f)
diff --git a/src/checks.c b/src/checks.c
index 3059d57..502d905 100644
--- a/src/checks.c
+++ b/src/checks.c
@@ -47,6 +47,8 @@
#include <proto/server.h>
#include <proto/task.h>
+static int httpchk_expect(struct server *s, int done);
+
const struct check_status check_statuses[HCHK_STATUS_SIZE] = {
[HCHK_STATUS_UNKNOWN] = { SRV_CHK_UNKNOWN, "UNK", "Unknown" },
[HCHK_STATUS_INI] = { SRV_CHK_UNKNOWN, "INI", "Initializing" },
@@ -938,21 +940,24 @@
}
s->check_code = str2uic(s->check_data + 9);
-
desc = ltrim(s->check_data + 12, ' ');
- /* check the reply : HTTP/1.X 2xx and 3xx are OK */
- if (*(s->check_data + 9) == '2' || *(s->check_data + 9) == '3') {
- cut_crlf(desc);
- set_server_check_status(s, HCHK_STATUS_L7OKD, desc);
- }
- else if ((s->proxy->options & PR_O_DISABLE404) &&
- (s->state & SRV_RUNNING) &&
- (s->check_code == 404)) {
+ if ((s->proxy->options & PR_O_DISABLE404) &&
+ (s->state & SRV_RUNNING) && (s->check_code == 404)) {
/* 404 may be accepted as "stopping" only if the server was up */
cut_crlf(desc);
set_server_check_status(s, HCHK_STATUS_L7OKCD, desc);
}
+ else if (s->proxy->options2 & PR_O2_EXP_TYPE) {
+ /* Run content verification check... We know we have at least 13 chars */
+ if (!httpchk_expect(s, done))
+ goto wait_more_data;
+ }
+ /* check the reply : HTTP/1.X 2xx and 3xx are OK */
+ else if (*(s->check_data + 9) == '2' || *(s->check_data + 9) == '3') {
+ cut_crlf(desc);
+ set_server_check_status(s, HCHK_STATUS_L7OKD, desc);
+ }
else {
cut_crlf(desc);
set_server_check_status(s, HCHK_STATUS_L7STS, desc);
@@ -1518,6 +1523,107 @@
}
/*
+ * Perform content verification check on data in s->check_data buffer.
+ * The buffer MUST be terminated by a null byte before calling this function.
+ * Sets server status appropriately. The caller is responsible for ensuring
+ * that the buffer contains at least 13 characters. If <done> is zero, we may
+ * return 0 to indicate that data is required to decide of a match.
+ */
+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;
+ int crlf;
+ int ret;
+
+ switch (s->proxy->options2 & PR_O2_EXP_TYPE) {
+ case PR_O2_EXP_STS:
+ case PR_O2_EXP_RSTS:
+ memcpy(status_code, s->check_data + 9, 3);
+ memcpy(status_msg + strlen(status_msg) - 4, s->check_data + 9, 3);
+
+ if ((s->proxy->options2 & PR_O2_EXP_TYPE) == PR_O2_EXP_STS)
+ ret = strncmp(s->proxy->expect_str, status_code, 3) == 0;
+ else
+ ret = regexec(s->proxy->expect_regex, status_code, MAX_MATCH, pmatch, 0) == 0;
+
+ /* we necessarily have the response, so there are no partial failures */
+ if (s->proxy->options2 & PR_O2_EXP_INV)
+ ret = !ret;
+
+ set_server_check_status(s, ret ? HCHK_STATUS_L7OKD : HCHK_STATUS_L7STS, status_msg);
+ break;
+
+ case PR_O2_EXP_STR:
+ case PR_O2_EXP_RSTR:
+ /* very simple response parser: ignore CR and only count consecutive LFs,
+ * stop with contentptr pointing to first char after the double CRLF or
+ * to '\0' if crlf < 2.
+ */
+ crlf = 0;
+ for (contentptr = s->check_data; *contentptr; contentptr++) {
+ if (crlf >= 2)
+ break;
+ if (*contentptr == '\r')
+ continue;
+ else if (*contentptr == '\n')
+ crlf++;
+ else
+ crlf = 0;
+ }
+
+ /* Check that response contains a body... */
+ if (crlf < 2) {
+ if (!done)
+ return 0;
+
+ set_server_check_status(s, HCHK_STATUS_L7RSP,
+ "HTTP content check could not find a response body");
+ return 1;
+ }
+
+ /* Check that response body is not empty... */
+ if (*contentptr == '\0') {
+ set_server_check_status(s, HCHK_STATUS_L7RSP,
+ "HTTP content check found empty response body");
+ return 1;
+ }
+
+ /* Check the response content against the supplied string
+ * or regex... */
+ if ((s->proxy->options2 & PR_O2_EXP_TYPE) == PR_O2_EXP_STR)
+ ret = strstr(contentptr, s->proxy->expect_str) != NULL;
+ else
+ ret = regexec(s->proxy->expect_regex, contentptr, MAX_MATCH, pmatch, 0) == 0;
+
+ /* if we don't match, we may need to wait more */
+ if (!ret && !done)
+ return 0;
+
+ if (ret) {
+ /* content matched */
+ if (s->proxy->options2 & PR_O2_EXP_INV)
+ set_server_check_status(s, HCHK_STATUS_L7RSP,
+ "HTTP check matched unwanted content");
+ else
+ set_server_check_status(s, HCHK_STATUS_L7OKD,
+ "HTTP content check matched");
+ }
+ else {
+ if (s->proxy->options2 & PR_O2_EXP_INV)
+ set_server_check_status(s, HCHK_STATUS_L7OKD,
+ "HTTP check did not match unwanted content");
+ else
+ set_server_check_status(s, HCHK_STATUS_L7RSP,
+ "HTTP content check did not match");
+ }
+ break;
+ }
+ return 1;
+}
+
+/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8