MINOR: httpclient: allow ipv4 or ipv6 preference for resolving

The httpclient.resolvers.prefer global keyword allows to configure an
ipv4 or ipv6 preference when resolving. This could be useful in
environment where the ipv6 is not supported.

diff --git a/src/http_client.c b/src/http_client.c
index 02957cefc010dc322e4c44e09b04c97419983960..4de00bf0e0df137a2812f1c5e62674e220d16f55 100644 (file)
--- a/src/http_client.c
+++ b/src/http_client.c
@@ -52,8 +52,10 @@ static char *httpclient_ssl_ca_file = NULL;
 #endif
 static struct applet httpclient_applet;
 
+/* if the httpclient is not configured, error are ignored and features are limited */
 static int hard_error_resolvers = 0;
 static char *resolvers_id = NULL;
+static char *resolvers_prefer = NULL;
 
 /* --- This part of the file implement an HTTP client over the CLI ---
  * The functions will be  starting by "hc_cli" for "httpclient cli"
@@ -1069,7 +1071,7 @@ static int httpclient_resolve_init()
        if (!resolvers_id)
                resolvers_id = strdup("default");
 
-       memprintf(&do_resolve, "do-resolve(txn.hc_ip,%s)", resolvers_id);
+       memprintf(&do_resolve, "do-resolve(txn.hc_ip,%s%s%s)", resolvers_id, resolvers_prefer ? "," : "", resolvers_prefer ? resolvers_prefer : "");
        http_rules[1][0] = do_resolve;
 
        /* if the resolver does not exist and no hard_error was set, simply ignore resolving */
@@ -1310,6 +1312,28 @@ static int httpclient_parse_global_resolvers(char **args, int section_type, stru
        return 0;
 }
 
+static int httpclient_parse_global_prefer(char **args, int section_type, struct proxy *curpx,
+                                        const struct proxy *defpx, const char *file, int line,
+                                        char **err)
+{
+       if (too_many_args(1, args, err, NULL))
+               return -1;
+
+       /* any configuration should set the hard_error flag */
+       hard_error_resolvers = 1;
+
+
+       if (strcmp(args[1],"ipv4") == 0)
+               resolvers_prefer = "ipv4";
+       else if (strcmp(args[1],"ipv6") == 0)
+               resolvers_prefer = "ipv6";
+       else {
+               ha_alert("parsing [%s:%d] : '%s' expects 'ipv4' or 'ipv6' as argument.\n", file, line, args[0]);
+               return -1;
+       }
+
+       return 0;
+}
 
 
 #ifdef USE_OPENSSL
@@ -1354,6 +1378,7 @@ static int httpclient_parse_global_verify(char **args, int section_type, struct
 
 static struct cfg_kw_list cfg_kws = {ILH, {
        { CFG_GLOBAL, "httpclient.resolvers.id", httpclient_parse_global_resolvers },
+       { CFG_GLOBAL, "httpclient.resolvers.prefer", httpclient_parse_global_prefer },
 #ifdef USE_OPENSSL
        { CFG_GLOBAL, "httpclient.ssl.verify", httpclient_parse_global_verify },
        { CFG_GLOBAL, "httpclient.ssl.ca-file", httpclient_parse_global_ca_file },