plugin: add queue validation

Add validation for an optional queue argument
when a job is submitted. The queue is first checked
to exist in the queues map. It is then checked to
determine if it is a valid queue for a user/bank to specify
when submitting their job.

If no queue is specified, the plugin will look for a "default"
queue and use its associated priority. If no default queue is
added, jobs trying to use this default queue will be rejected
with a message saying that no default queue exists. It is up
to the sys admin or scheduler operator to ensure that at least
a default queue exists in the queue_table of the flux-accounting
DB.

If all checks pass, the queue's associated integer priority
is added to the bank_info struct for the user/bank job.

src/plugins/mf_priority.cpp

@@ -305,19 +305,21 @@ static int validate_cb (flux_plugin_t *p,
 {
     int userid;
     char *bank = NULL;
+    char *queue = NULL;
     int max_run_jobs, cur_active_jobs, max_active_jobs = 0;
     double fairshare = 0.0;
 
     std::map<int, std::map<std::string, struct bank_info>>::iterator it;
     std::map<std::string, struct bank_info>::iterator bank_it;
+    std::map<std::string, struct queue_info>::iterator q_it;
 
     flux_t *h = flux_jobtap_get_flux (p);
     if (flux_plugin_arg_unpack (args,
                                 FLUX_PLUGIN_ARG_IN,
-                                "{s:i, s{s{s{s?s}}}}",
+                                "{s:i, s{s{s{s?s, s?s}}}}",
                                 "userid", &userid,
                                 "jobspec", "attributes", "system",
-                                "bank", &bank) < 0) {
+                                "bank", &bank, "queue", &queue) < 0) {
         return flux_jobtap_reject_job (p, args, "unable to unpack bank arg");
     }
 
@@ -342,6 +344,35 @@ static int validate_cb (flux_plugin_t *p,
                                      "user/default bank entry does not exist");
     }
 
+    // make sure that if a queue is passed in, it 1) exists, and 2) is a valid
+    // queue for the user to run jobs in
+    if (queue != NULL) {
+        // check #1) the queue passed in exists in the queues map
+        q_it = queues.find (queue);
+        if (q_it == queues.end ())
+            return flux_jobtap_reject_job (p, args, "Queue does not exist");
+
+        // check #2) the queue passed in is a valid option to pass for user
+        std::vector<std::string>::iterator vect_it;
+        vect_it = std::find (bank_it->second.queues.begin (),
+                             bank_it->second.queues.end (), queue);
+
+        if (vect_it == bank_it->second.queues.end ())
+            return flux_jobtap_reject_job (p, args, "Queue not valid for user");
+        else
+            // add priority associated with the passed in queue to bank_info
+            bank_it->second.queue_factor = queues[queue].priority;
+    } else {
+        // no queue was specified, so use default queue and associated priority
+        q_it = queues.find ("default");
+
+        if (q_it == queues.end ())
+            return flux_jobtap_reject_job (p, args, "No default queue exists");
+        else
+            // add priority associated with the passed in queue to bank_info
+            bank_it->second.queue_factor = queues["default"].priority;
+    }
+
     max_run_jobs = bank_it->second.max_run_jobs;
     fairshare = bank_it->second.fairshare;
     cur_active_jobs = bank_it->second.cur_active_jobs;