Merge pull request #3653 from garlick/proxy_version

flux-proxy: add flux-core version check

doc/man1/flux-proxy.rst

@@ -9,7 +9,7 @@ flux-proxy(1)
 SYNOPSIS
 ========
 
-**flux** **proxy** URI [command [args...]]
+**flux** **proxy** [*OPTIONS*] URI [command [args...]]
 
 DESCRIPTION
 ===========
@@ -26,6 +26,13 @@ for example where connection establishment has high latency or
 requires authentication.
 
 
+OPTIONS
+=======
+
+**-f, --force**
+   Allow the proxy command to connect to a broker running a different
+   version of Flux with a warning message instead of a fatal error.
+
 EXAMPLES
 ========
 

src/broker/broker.c

@@ -639,8 +639,9 @@ static void init_attrs (attr_t *attrs, pid_t pid, struct flux_msg_cred *cred)
     init_attrs_rc_paths (attrs);
     init_attrs_shell_paths (attrs);
 
-    if (attr_add (attrs, "version", FLUX_CORE_VERSION_STRING,
-                                            FLUX_ATTRFLAG_IMMUTABLE) < 0)
+    /* Allow version to be changed by instance owner for testing
+     */
+    if (attr_add (attrs, "version", FLUX_CORE_VERSION_STRING, 0) < 0)
         log_err_exit ("attr_add version");
 
     char tmp[32];

src/cmd/builtin/proxy.c

@@ -222,6 +222,34 @@ static void acceptor_cb (struct usock_conn *uconn, void *arg)
     usock_conn_destroy (uconn);
 }
 
+/* Compare proxy version with broker version.
+ * Require major, minor, and patch numbers to match, ignoring patch suffix.
+ */
+static void version_check (flux_t *h, bool force)
+{
+    unsigned int n[3];
+    const char *version;
+
+    if (!(version = flux_attr_get (h, "version")))
+        log_err_exit ("flux_attr_get version");
+    if (sscanf (version, "%u.%u.%u", &n[0], &n[1], &n[2]) != 3
+        || n[0] != FLUX_CORE_VERSION_MAJOR
+        || n[1] != FLUX_CORE_VERSION_MINOR
+        || n[2] != FLUX_CORE_VERSION_PATCH) {
+        if (force) {
+            log_msg ("warning: proxy version %s != broker version %s",
+                      FLUX_CORE_VERSION_STRING,
+                      version);
+        }
+        else {
+            log_msg_exit ("fatal: proxy version %s != broker version %s "
+                          "(--force to connect anyway)",
+                          FLUX_CORE_VERSION_STRING,
+                          version);
+        }
+    }
+}
+
 static int cmd_proxy (optparse_t *p, int ac, char *av[])
 {
     int n;
@@ -250,6 +278,10 @@ static int cmd_proxy (optparse_t *p, int ac, char *av[])
     if (flux_set_reactor (ctx.h, r) < 0)
         log_err_exit ("flux_set_reactor");
 
+    /* Check proxy version vs broker version
+     */
+    version_check (ctx.h, optparse_hasopt (p, "force"));
+
     /* Create router
      */
     if (!(ctx.router = router_create (ctx.h)))
@@ -296,6 +328,12 @@ static int cmd_proxy (optparse_t *p, int ac, char *av[])
     return (0);
 }
 
+static struct optparse_option proxy_opts[] = {
+    { .name = "force",  .key = 'f',  .has_arg = 0,
+      .usage = "Skip version check when connecting to Flux broker", },
+    OPTPARSE_TABLE_END,
+};
+
 int subcommand_proxy_register (optparse_t *p)
 {
     optparse_err_t e;
@@ -304,7 +342,7 @@ int subcommand_proxy_register (optparse_t *p)
         "[OPTIONS] URI [COMMAND...]",
         "Route messages to/from Flux instance",
         0,
-        NULL);
+        proxy_opts);
     if (e != OPTPARSE_SUCCESS)
         return (-1);
 

t/t1105-proxy.t

@@ -81,4 +81,18 @@ test_expect_success 'flux-proxy forwards LD_LIBRARY_PATH' '
 	grep -E "ssh.* LD_LIBRARY_PATH=[^ ]*:?/foo .*/flux relay" ./proxinator.log
 '
 
+test_expect_success 'set bogus broker version' '
+	flux getattr version >realversion &&
+	flux setattr version 0.0.0
+'
+test_expect_success 'flux-proxy fails with version mismatch' '
+	test_must_fail flux proxy $FLUX_URI /bin/true
+'
+test_expect_success 'flux-proxy --force works with version mismatch' '
+	flux proxy --force $FLUX_URI /bin/true
+'
+test_expect_success 'restore real broker version' '
+	flux setattr version $(cat realversion)
+'
+
 test_done