Add option to use a custom field for GitHub user matching

app/lib/github_badges.rb

@@ -11,9 +11,12 @@ module GithubBadges
     COMMITTER_BADGE_NAME_GOLD ||= "Amazing Committer"
 
     class Granter
-      def initialize(emails)
+      def initialize(emails, custom_user_field)
         @emails = emails
         @badges = []
+        # The custom user field that stores the user's GitHub username, if
+        # specified.
+        @custom_user_field = custom_user_field
       end
 
       def add_badge(badge, as_title:, threshold:)
@@ -52,6 +55,18 @@ def grant!
               .map { |row| [row.user, row.info["nickname"]] }
               .to_h
 
+          # If we don't have any screen names, look in the custom user field, if
+          # specified.
+          if screen_names.empty? && @custom_user_field
+            screen_names =
+              UserCustomField
+                .where(name: @custom_user_field)
+                .where("value IN (?)", github_name_email.keys)
+                .includes(:user)
+                .map { |row| [row.user, row.value] }
+                .to_h
+          end
+
           screen_names.each do |user, screen_name|
             user_emails[user] ||= []
             user_emails[user] << github_name_email[screen_name]
@@ -83,7 +98,7 @@ def self.grant_committer_badges!
 
       bronze, silver, gold = committer_badges
 
-      granter = GithubBadges::Granter.new(emails)
+      granter = GithubBadges::Granter.new(emails, SiteSetting.github_user_custom_field)
       granter.add_badge(bronze, as_title: false, threshold: 1)
       granter.add_badge(silver, as_title: true, threshold: 25)
       granter.add_badge(gold, as_title: true, threshold: 1000)
@@ -99,7 +114,7 @@ def self.grant_contributor_badges!
 
       bronze, silver, gold = contributor_badges
 
-      granter = GithubBadges::Granter.new(emails)
+      granter = GithubBadges::Granter.new(emails, SiteSetting.github_user_custom_field)
       granter.add_badge(bronze, as_title: false, threshold: 1)
       granter.add_badge(
         silver,

config/locales/server.en.yml

@@ -11,6 +11,7 @@ en:
     github_badges_repos: "URLs of the GitHub repos to scan for contributions and commits"
     github_silver_badge_min_commits: "Minumum number of commits for silver badge"
     github_gold_badge_min_commits: "Minumum number of commits for gold badge"
+    github_user_custom_field: "Optional custom field that stores the GitHub username for verification"
 
     errors:
       invalid_badge_repo: "You must provide a GitHub URL or the repository name in the format github_user/repository_name"

config/settings.yml

@@ -29,3 +29,5 @@ discourse_github:
   github_gold_badge_min_commits:
     default: 250
     min: 1
+  github_user_custom_field:
+    default: ""