CA-399638: The livepatches are absent in the response of /updates (#6017

)

When applying livepatches, for one component, only the latest one will
be applied. This is because the latest livepatch will always roll up all
the previous ones if they are of the same component and base build ID.

The bug to be fixed in this commit is that the previous livepatches with
the same build ID are not returned in the response of the query on
the /updates HTTP endpoint.

ocaml/tests/test_repository_helpers.ml

@@ -3881,7 +3881,29 @@ module PruneUpdateInfoForLivepatches = Generic.MakeStateless (struct
       ; base_build_id= "2cc28689364587682593b6a72e2a586d29996bb9"
       ; base_version= "4.19.19"
       ; base_release= "8.0.20.xs8"
-      ; to_version= "4.13.4"
+      ; to_version= "4.19.19"
+      ; to_release= "8.0.21.xs8"
+      }
+
+  let lp2 =
+    LivePatch.
+      {
+        component= Livepatch.Kernel
+      ; base_build_id= "2cc28689364587682593b6a72e2a586d29996bb9"
+      ; base_version= "4.19.19"
+      ; base_release= "8.0.20.xs8"
+      ; to_version= "4.19.20"
+      ; to_release= "8.0.21.xs8"
+      }
+
+  let lp3 =
+    LivePatch.
+      {
+        component= Livepatch.Kernel
+      ; base_build_id= "4cc28689364587682593b6a72e2a586d29996bb9"
+      ; base_version= "4.19.20"
+      ; base_release= "7.0.20.xs8"
+      ; to_version= "4.13.5"
       ; to_release= "8.0.21.xs8"
       }
 
@@ -3915,6 +3937,12 @@ module PruneUpdateInfoForLivepatches = Generic.MakeStateless (struct
       ; ( ([], {updateinfo with livepatches= [lp0; lp1]})
         , {updateinfo with livepatches= []}
         )
+      ; ( ([lp0; lp2], {updateinfo with livepatches= [lp0; lp1; lp2; lp3]})
+        , {updateinfo with livepatches= [lp0; lp1; lp2]}
+        )
+      ; ( ([lp0], {updateinfo with livepatches= [lp0; lp1; lp2; lp3]})
+        , {updateinfo with livepatches= [lp0]}
+        )
       ]
 end)
 

ocaml/xapi/repository_helpers.ml

@@ -1298,12 +1298,22 @@ let with_access_token ~token ~token_id f =
       let msg = Printf.sprintf "%s: The token or token_id is empty" __LOC__ in
       raise Api_errors.(Server_error (internal_error, [msg]))
 
-let prune_updateinfo_for_livepatches livepatches updateinfo =
-  let open UpdateInfo in
-  let lps =
-    List.filter (fun x -> LivePatchSet.mem x livepatches) updateinfo.livepatches
+let prune_updateinfo_for_livepatches latest_lps updateinfo =
+  let livepatches =
+    let open LivePatch in
+    (* Keep a livepatch if it is rolled up by one of the latest livepatches.
+     * The latest livepatches are the ones to be applied actually.
+     *)
+    updateinfo.UpdateInfo.livepatches
+    |> List.filter (fun lp ->
+           let is_rolled_up_by latest =
+             latest.component = lp.component
+             && latest.base_build_id = lp.base_build_id
+           in
+           LivePatchSet.exists is_rolled_up_by latest_lps
+       )
   in
-  {updateinfo with livepatches= lps}
+  {updateinfo with livepatches}
 
 let do_with_host_pending_guidances ~op guidances =
   List.iter