From 7e33bdc70eb397882fbe989fee1fa00385335917 Mon Sep 17 00:00:00 2001
From: Paul Buetow <paul@buetow.org>
Date: Sat, 20 May 2023 01:35:31 +0300
Subject: can determine the winner

---
 internal/quorum.go      |  9 +++++++++
 internal/quorum_test.go | 10 ++++++++++
 internal/run.go         |  7 +++++++
 3 files changed, 26 insertions(+)

(limited to 'internal')

diff --git a/internal/quorum.go b/internal/quorum.go
index 032ebc8..b506bfb 100644
--- a/internal/quorum.go
+++ b/internal/quorum.go
@@ -1,6 +1,7 @@
 package internal
 
 import (
+	"fmt"
 	"log"
 	"sort"
 )
@@ -17,6 +18,14 @@ func (q quorumMap) vote(v vote) {
 	q[v.from] = v
 }
 
+func (q quorumMap) winner(config config) (string, error) {
+	scores := q.score(config)
+	if len(scores) == 0 {
+		return "", fmt.Errorf("unable to find a winner, empty score list")
+	}
+	return scores[0].id, nil
+}
+
 func (q quorumMap) score(config config) (scores []score) {
 	q.cleanExpired()
 	scoreMap := make(map[string]int)
diff --git a/internal/quorum_test.go b/internal/quorum_test.go
index da2abdd..d4790f9 100644
--- a/internal/quorum_test.go
+++ b/internal/quorum_test.go
@@ -64,6 +64,11 @@ func TestTieScore(t *testing.T) {
 		if scores[0].id != "foo" || scores[0].score != 3 {
 			t.Errorf("Expected score[0] to be {foo,3}: %v", scores[0])
 		}
+
+		winner, _ := quorum.winner(config)
+		if winner != "foo" {
+			t.Errorf("Expected the winner to be foo but is: %s", winner)
+		}
 	})
 
 	t.Run("Second tie score test", func(t *testing.T) {
@@ -80,6 +85,11 @@ func TestTieScore(t *testing.T) {
 		if scores[0].id != "bar" || scores[0].score != 3 {
 			t.Errorf("Expected score[0] to be {bar,3}: %v", scores[0])
 		}
+
+		winner, _ := quorum.winner(config)
+		if winner != "bar" {
+			t.Errorf("Expected the winner to be bar but is: %s", winner)
+		}
 	})
 }
 
diff --git a/internal/run.go b/internal/run.go
index 8b7faa9..8f73b19 100644
--- a/internal/run.go
+++ b/internal/run.go
@@ -2,6 +2,7 @@ package internal
 
 import (
 	"context"
+	"log"
 )
 
 func Run(ctx context.Context, configFile string) {
@@ -18,6 +19,12 @@ func Run(ctx context.Context, configFile string) {
 			select {
 			case vote := <-ch:
 				quorum.vote(vote)
+				winner, err := quorum.winner(config)
+				if err != nil {
+					log.Println(err.Error())
+					continue
+				}
+				log.Printf("The current leader node is %s", winner)
 			case <-ctx.Done():
 				return
 			}
-- 
cgit v1.2.3