From fc0cceb08a5e11a5e767e3a1d4d44901c454a850 Mon Sep 17 00:00:00 2001 From: Maximilian Mader Date: Sun, 6 Jun 2021 00:50:22 +0200 Subject: [PATCH] MINOR: haproxy: Add `-cc` argument This patch adds the `-cc` (check condition) argument to evaluate conditions on startup and return the result as the exit code. As an example this can be used to easily check HAProxy's version in scripts: haproxy -cc 'version_atleast(2.4)' This resolves GitHub issue #1246. Co-authored-by: Tim Duesterhus --- doc/configuration.txt | 3 ++ doc/management.txt | 4 ++ include/haproxy/cfgparse.h | 1 + include/haproxy/global-t.h | 1 + reg-tests/startup/check_condition.vtc | 13 ++++++ src/cfgparse.c | 2 +- src/haproxy.c | 62 ++++++++++++++++++++++++++- 7 files changed, 84 insertions(+), 2 deletions(-) create mode 100644 reg-tests/startup/check_condition.vtc diff --git a/doc/configuration.txt b/doc/configuration.txt index 5b1768e89..1fb6094aa 100644 --- a/doc/configuration.txt +++ b/doc/configuration.txt @@ -802,6 +802,9 @@ Comments may be placed on the same line if needed after a '#', they will be ignored. The directives are tokenized like other configuration directives, and as such it is possible to use environment variables in conditions. +Conditions can also be evaluated on startup with the -cc parameter. +See "3. Starting HAProxy" in the management doc. + The conditions are currently limited to: - an empty string, always returns "false" diff --git a/doc/management.txt b/doc/management.txt index b1ef55ec2..39c3a3160 100644 --- a/doc/management.txt +++ b/doc/management.txt @@ -195,6 +195,10 @@ list of options is : to bind. The exit status is zero if everything is OK, or non-zero if an error is encountered. Presence of warnings will be reported if any. + -cc : evaluates a condition as used within a conditional block of the + configuration. The exit status is zero if the condition is true, 1 if the + condition is false or 2 if an error is encountered. + -d : enable debug mode. This disables daemon mode, forces the process to stay in foreground and to show incoming and outgoing events. It must never be used in an init script. diff --git a/include/haproxy/cfgparse.h b/include/haproxy/cfgparse.h index 1c97a88b9..51e5b9edf 100644 --- a/include/haproxy/cfgparse.h +++ b/include/haproxy/cfgparse.h @@ -126,6 +126,7 @@ void free_email_alert(struct proxy *p); const char *cfg_find_best_match(const char *word, const struct list *list, int section, const char **extra); int warnifnotcap(struct proxy *proxy, int cap, const char *file, int line, const char *arg, const char *hint); int failifnotcap(struct proxy *proxy, int cap, const char *file, int line, const char *arg, const char *hint); +int cfg_eval_condition(char **args, char **err, const char **errptr); /* simplified way to define a section parser */ #define REGISTER_CONFIG_SECTION(name, parse, post) \ diff --git a/include/haproxy/global-t.h b/include/haproxy/global-t.h index 1bdbc1bbc..057d90e61 100644 --- a/include/haproxy/global-t.h +++ b/include/haproxy/global-t.h @@ -38,6 +38,7 @@ #define MODE_MWORKER_WAIT 0x100 /* Master Worker wait mode */ #define MODE_ZERO_WARNING 0x200 /* warnings cause a failure */ #define MODE_DIAG 0x400 /* extra warnings */ +#define MODE_CHECK_CONDITION 0x800 /* -cc mode */ /* list of last checks to perform, depending on config options */ #define LSTCHK_CAP_BIND 0x00000001 /* check that we can bind to any port */ diff --git a/reg-tests/startup/check_condition.vtc b/reg-tests/startup/check_condition.vtc new file mode 100644 index 000000000..7d3324bfe --- /dev/null +++ b/reg-tests/startup/check_condition.vtc @@ -0,0 +1,13 @@ +varnishtest "Tests the -cc argument" + +#REQUIRE_VERSION=2.5 +feature cmd "$HAPROXY_PROGRAM -cc 'version_atleast(2.5-dev0)'" + +shell { + $HAPROXY_PROGRAM -cc "version_atleast(2.4)" + ! $HAPROXY_PROGRAM -cc "version_atleast(1024)" + + $HAPROXY_PROGRAM -cc "streq(foo,'foo')" + $HAPROXY_PROGRAM -cc "streq(\"foo bar\",'foo bar')" + ! $HAPROXY_PROGRAM -cc "streq(foo,bar)" +} -run diff --git a/src/cfgparse.c b/src/cfgparse.c index 0f8ad579d..dc31ecae2 100644 --- a/src/cfgparse.c +++ b/src/cfgparse.c @@ -1736,7 +1736,7 @@ static const struct cond_pred_kw *cfg_lookup_cond_pred(const char *str) * and only in this case), 0 if the condition is false, 1 if it's true. If * is not NULL, it's set to the first invalid character on error. */ -static int cfg_eval_condition(char **args, char **err, const char **errptr) +int cfg_eval_condition(char **args, char **err, const char **errptr) { const struct cond_pred_kw *cond_pred = NULL; const char *end_ptr; diff --git a/src/haproxy.c b/src/haproxy.c index 3ac6ed9cf..60435002c 100644 --- a/src/haproxy.c +++ b/src/haproxy.c @@ -570,6 +570,7 @@ static void usage(char *name) #endif " -q quiet mode : don't display messages\n" " -c check mode : only check config files and exit\n" + " -cc check condition : evaluate a condition and exit\n" " -n sets the maximum total # of connections (uses ulimit -n)\n" " -m limits the usable amount of memory (in MB)\n" " -N sets the default, per-proxy maximum # of connections (%d)\n" @@ -1464,6 +1465,7 @@ static void init(int argc, char **argv) struct proxy *px; struct post_check_fct *pcf; int ideal_maxconn; + char *check_condition = NULL; global.mode = MODE_STARTING; old_argv = copy_argv(argc, argv); @@ -1619,6 +1621,12 @@ static void init(int argc, char **argv) global.tune.options |= GTUNE_RESOLVE_DONTFAIL; else if (*flag == 'd') arg_mode |= MODE_DEBUG; + else if (*flag == 'c' && flag[1] == 'c') { + arg_mode |= MODE_CHECK_CONDITION; + argv++; + argc--; + check_condition = *argv; + } else if (*flag == 'c') arg_mode |= MODE_CHECK; else if (*flag == 'D') @@ -1752,7 +1760,7 @@ static void init(int argc, char **argv) global.mode |= (arg_mode & (MODE_DAEMON | MODE_MWORKER | MODE_FOREGROUND | MODE_VERBOSE | MODE_QUIET | MODE_CHECK | MODE_DEBUG | MODE_ZERO_WARNING - | MODE_DIAG)); + | MODE_DIAG | MODE_CHECK_CONDITION)); if (getenv("HAPROXY_MWORKER_WAIT_ONLY")) { unsetenv("HAPROXY_MWORKER_WAIT_ONLY"); @@ -1787,6 +1795,58 @@ static void init(int argc, char **argv) usermsgs_clr("config"); + if (global.mode & MODE_CHECK_CONDITION) { + int result; + + uint32_t err; + const char *errptr; + char *errmsg = NULL; + + char *args[MAX_LINE_ARGS+1]; + int arg = sizeof(args) / sizeof(*args); + size_t outlen = strlen(check_condition) + 1; + + err = parse_line(check_condition, check_condition, &outlen, args, &arg, + PARSE_OPT_DQUOTE | PARSE_OPT_SQUOTE | PARSE_OPT_BKSLASH, + &errptr); + + if (err & PARSE_ERR_QUOTE) { + ha_alert("Syntax Error in condition: Unmatched quote.\n"); + exit(2); + } + + if (err & PARSE_ERR_HEX) { + ha_alert("Syntax Error in condition: Truncated or invalid hexadecimal sequence.\n"); + exit(2); + } + + if (err & (PARSE_ERR_TOOLARGE|PARSE_ERR_OVERLAP)) { + ha_alert("Error in condition: Line too long.\n"); + exit(2); + } + + if (err & PARSE_ERR_TOOMANY) { + ha_alert("Error in condition: Too many words.\n"); + exit(2); + } + + if (err) { + ha_alert("Unhandled error in condition, please report this to the developers.\n"); + exit(2); + } + + result = cfg_eval_condition(args, &errmsg, &errptr); + + if (result < 0) { + if (errmsg) + ha_alert("Failed to evaluate condition: %s\n", errmsg); + + exit(2); + } + + exit(result ? 0 : 1); + } + /* in wait mode, we don't try to read the configuration files */ if (!(global.mode & MODE_MWORKER_WAIT)) { char *env_cfgfiles = NULL;