cfg: change project owner syntax to record list

Author: yasunariw

documentation/config_docs.md

@@ -258,8 +258,16 @@ Note that the owner of the personal access token cannot be a project owner, as G
 {
     ...,
     "project_owners": {
-        "Label 1": ["user1", "user2", "org/team1"],
-        "Label 2": ["org/team2", "user3"]
+        "rules": [
+            {
+                "label": "Label 1",
+                "owners": ["user1", "user2", "org/team1"]
+            },
+            {
+                "label": "Label 2",
+                "owners": ["org/team2", "user3"]
+            }
+        ]
     },
     ...
 }

lib/config.atd

@@ -1,7 +1,7 @@
 type status_rule <ocaml from="Rule"> = abstract
 type prefix_rule <ocaml from="Rule"> = abstract
 type label_rule <ocaml from="Rule"> = abstract
-type 'v map_as_object <ocaml from="Common"> = abstract
+type project_owners_rule <ocaml from="Rule"> = abstract
 
 (* This type of rule is used for CI build notifications. *)
 type status_rules = {
@@ -23,13 +23,18 @@ type label_rules = {
   rules: label_rule list;
 }
 
+(* This type of rule is used for routing PR review requests to users. *)
+type project_owners = {
+  rules: project_owners_rule list;
+}
+
 (* This is the structure of the repository configuration file. It should be at the
    root of the monorepo, on the main branch. *)
 type config = {
   prefix_rules : prefix_rules;
   label_rules : label_rules;
   ~status_rules <ocaml default="{allowed_pipelines = Some []; rules = []}"> : status_rules;
-  ~project_owners <ocaml default="Common.StringMap.empty"> : string list map_as_object;
+  ~project_owners <ocaml default="{rules = []}"> : project_owners;
   ?main_branch_name : string nullable; (* the name of the main branch; used to filter out notifications about merges of main branch into other branches *)
 }
 

lib/github.ml

@@ -140,12 +140,8 @@ let gh_link_of_string url_str =
     end
   | _ | (exception Re2.Exceptions.Regex_match_failed _) -> None
 
-let get_project_owners (labels : label list) project_owners_map =
-  List.fold_left labels ~init:[] ~f:(fun acc label ->
-    match Map.find_multi project_owners_map label.name with
-    | [] -> acc
-    | reviewers -> List.rev_append reviewers acc
-  )
+let get_project_owners (labels : label list) ({ rules } : Config_t.project_owners) =
+  List.fold_left labels ~init:[] ~f:(fun acc l -> List.rev_append (Rule.Project_owners.match_rules l ~rules) acc)
   |> List.dedup_and_sort ~compare:String.compare
   |> List.partition_map ~f:(fun reviewer ->
        try

lib/rule.atd

@@ -79,4 +79,13 @@ type label_rule = {
   ?allow <json name="match"> : string list nullable;
   ?ignore : string list nullable;
   channel_name <json name="channel"> : string;
-}
+}
+
+(* Requests reviews from [owners] if a PR is labeled with [label]. Owner format:
+   - users: "username"
+   - teams: "org/team"
+*)
+type project_owners_rule = {
+  label: string;
+  owners: string list;
+}

lib/rule.ml

@@ -125,3 +125,10 @@ module Label = struct
          Stdio.printf " -> #%s\n%!" rule.channel_name
        )
 end
+
+module Project_owners = struct
+  let match_rules (l : Github_t.label) ~rules =
+    match List.find rules ~f:(fun { label; _ } -> String.equal label l.name) with
+    | Some { owners = []; _ } | None -> []
+    | Some { owners; _ } -> owners
+end