CA-399187: Allow gencert to be called without groupid (#5987)

Last year, an argument to determine the group id of the certificates
created
was added. This broke test clients, and there's no need no make it
compulsory
since there's a default value: -1.

Modify the binary so it can accept only 3 arguments like before, and
change the
help output to mention the group id.

This makes quite a few internal certificate tests to pass compare the
previous suite run 204647 to the new 204840

ocaml/gencert/gencert.ml

@@ -76,19 +76,34 @@ let () =
   let program_name = Sys.argv.(0) in
   let dbg = Printf.sprintf "%s - %f" program_name (Unix.gettimeofday ()) in
   (* if necessary use Unix.localtime to debug *)
-  D.debug "%s" dbg ;
-  match Sys.argv with
-  | [|_; path; _; _|] when Sys.file_exists path ->
-      D.info "file already exists at path (%s) - doing nothing" path ;
-      exit 0
-  | [|_; path; cert_gid; sni|] -> (
+  let sni_or_exit sni =
     match SNI.of_string sni with
     | Some sni ->
-        main ~dbg ~path ~cert_gid:(int_of_string cert_gid) ~sni ()
+        sni
     | None ->
         D.error "SNI must be default or xapi:pool, but got '%s'" sni ;
         exit 1
-  )
+  in
+  let gid_or_exit gid =
+    match int_of_string_opt gid with
+    | Some gid ->
+        gid
+    | None ->
+        D.error "GROUPID must be an integer, but got '%s'" gid ;
+        exit 1
+  in
+  D.debug "%s" dbg ;
+  match Sys.argv with
+  | ([|_; path; _|] | [|_; path; _; _|]) when Sys.file_exists path ->
+      D.info "file already exists at path (%s) - doing nothing" path ;
+      exit 0
+  | [|_; path; sni|] ->
+      let sni = sni_or_exit sni in
+      main ~dbg ~path ~cert_gid:(-1) ~sni ()
+  | [|_; path; cert_gid; sni|] ->
+      let sni = sni_or_exit sni in
+      let cert_gid = gid_or_exit cert_gid in
+      main ~dbg ~path ~cert_gid ~sni ()
   | _ ->
-      D.error "Usage: %s PATH (default|xapi:pool)" program_name ;
+      D.error "Usage: %s PATH [GROUPID] (default|xapi:pool)" program_name ;
       exit 1

ocaml/idl/datamodel_lifecycle.ml

@@ -68,7 +68,7 @@ let prototyped_of_field = function
   | "host", "last_software_update" ->
       Some "22.20.0"
   | "VM_guest_metrics", "netbios_name" ->
-      Some "24.27.0-next"
+      Some "24.28.0"
   | "VM", "groups" ->
       Some "24.19.1"
   | "VM", "pending_guidances_full" ->