gencert testing: use human-readable errors for validation (#6471)

This is done using the API errors, and quite useful when adding tests or
changing them to interpret the results

Author: psafont

ocaml/gencert/dune

@@ -64,6 +64,7 @@
     rresult
     x509
     xapi-consts
+    xapi-datamodel
     xapi-stdext-unix
   )
   (deps

ocaml/gencert/test_lib.ml

@@ -179,11 +179,20 @@ let test_valid_leaf_cert pem_leaf time pkey () =
   match validate_pem_chain ~pem_leaf ~pem_chain:None time pkey with
   | Ok _ ->
       ()
-  | Error (`Msg (_, msg)) ->
+  | Error (`Msg err) ->
+      let err_to_str (name, params) =
+        let Datamodel_types.{err_doc; err_params; _} =
+          Hashtbl.find Datamodel_errors.errors name
+        in
+        let args = List.combine err_params params in
+        Format.asprintf "%s %a" err_doc
+          Fmt.(Dump.list (pair ~sep:(Fmt.any ":@ ") string string))
+          args
+      in
       Alcotest.fail
         (Format.asprintf "Valid certificate could not be validated: %a"
-           Fmt.(Dump.list string)
-           msg
+           (Fmt.of_to_string err_to_str)
+           err
         )
 
 let test_invalid_cert pem_leaf time pkey error reason =

quality-gate.sh

@@ -110,7 +110,7 @@ unixgetenv () {
 }
 
 hashtblfind () {
-  N=34
+  N=35
   # Looks for all .ml files except the ones using Core.Hashtbl.find,
   # which already returns Option
   HASHTBLFIND=$(git grep -P -r --count 'Hashtbl.find(?!_opt)' -- '**/*.ml' ':!ocaml/xapi-storage-script/main.ml' | cut -d ':' -f 2 | paste -sd+ - | bc)