From 05556daf26afdb3350fb95b91b4a8c6b9bda0d80 Mon Sep 17 00:00:00 2001
From: Herman Schaaf <hermanschaaf@gmail.com>
Date: Sun, 28 Jul 2019 14:35:28 +0100
Subject: [PATCH] start implementation of database package

---
 .gitignore     |  2 ++
 database/db.go | 91 ++++++++++++++++++++++++++++++++++++++++++++++++++
 main.go        | 37 ++++++--------------
 3 files changed, 104 insertions(+), 26 deletions(-)
 create mode 100644 database/db.go

diff --git a/.gitignore b/.gitignore
index ab243a0..434864e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -28,3 +28,5 @@ _testmain.go
 _repos
 
 goreportcard.db
+
+var
\ No newline at end of file
diff --git a/database/db.go b/database/db.go
new file mode 100644
index 0000000..9a7c493
--- /dev/null
+++ b/database/db.go
@@ -0,0 +1,91 @@
+package database
+
+import (
+	"github.com/go-redis/redis"
+	"github.com/siddontang/ledisdb/config"
+	"github.com/siddontang/ledisdb/ledis"
+)
+
+type Database interface {
+	Get(string) (string, error)
+	Set(string, string) error
+	Close() error
+}
+
+// GetConnection connects to the Redis/Ledis database (or creates it if it does not exist, in the case of Ledis),
+// and creates a space for saving the repos, also only if it does not exist.
+func GetConnection(redisHost string) (Database, error) {
+	if redisHost == "" {
+		return newLedisDatabase()
+	}
+	return newRedisDatabase(redisHost)
+}
+
+type ledisDatabase struct {
+	connection *ledis.DB
+}
+
+func (l *ledisDatabase) Get(k string) (string, error) {
+	b, _ := l.connection.Get([]byte(k))
+	return string(b), nil
+}
+
+func (l *ledisDatabase) Set(k, v string) error {
+	return l.connection.Set([]byte(k), []byte(v))
+}
+
+func (l *ledisDatabase) Close() error {
+	return nil
+}
+
+func newLedisDatabase() (*ledisDatabase, error) {
+	db, err := connectLedis()
+	if err != nil {
+		return nil, err
+	}
+	return &ledisDatabase{connection: db}, nil
+}
+
+func connectLedis() (*ledis.DB, error) {
+	// connect to ledis
+	l, err := ledis.Open(config.NewConfigDefault())
+	if err != nil {
+		return nil, err
+	}
+	db, err := l.Select(0)
+	if err != nil {
+		return nil, err
+	}
+	return db, nil
+}
+
+type redisDatabase struct {
+	connection *redis.Client
+}
+
+func newRedisDatabase(redisHost string) (*redisDatabase, error) {
+	db := connectRedis(redisHost)
+	err := db.Echo("test").Err()
+	return &redisDatabase{connection: db}, err
+}
+
+func (r *redisDatabase) Get(k string) (string, error) {
+	return r.connection.Get(k).Result()
+}
+
+func (r *redisDatabase) Set(k, v string) error {
+	return r.connection.Set(k, v, 0).Err()
+}
+
+func (r *redisDatabase) Close() error {
+	return r.connection.Close()
+}
+
+func connectRedis(redisHost string) *redis.Client {
+	client := redis.NewClient(&redis.Options{
+		Addr:     redisHost,
+		Password: "", // no password set
+		DB:       0,  // use default DB
+	})
+	return client
+}
diff --git a/main.go b/main.go
index dc8a968..7139f3d 100644
--- a/main.go
+++ b/main.go
@@ -9,15 +9,17 @@ import (
 	"regexp"
 	"time"
 
+	"github.com/gojp/goreportcard/database"
+
 	"github.com/gojp/goreportcard/handlers"
 
-	"github.com/boltdb/bolt"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
 )
 
 var (
-	addr = flag.String("http", ":8000", "HTTP listen address")
+	addr      string
+	redisHost string
 )
 
 func makeHandler(name string, fn func(http.ResponseWriter, *http.Request, string)) http.HandlerFunc {
@@ -57,26 +59,6 @@ func makeHandler(name string, fn func(http.ResponseWriter, *http.Request, string
 	}
 }
 
-// initDB opens the bolt database file (or creates it if it does not exist), and creates
-// a bucket for saving the repos, also only if it does not exist.
-func initDB() error {
-	db, err := bolt.Open(handlers.DBPath, 0600, &bolt.Options{Timeout: 1 * time.Second})
-	if err != nil {
-		return err
-	}
-	defer db.Close()
-
-	err = db.Update(func(tx *bolt.Tx) error {
-		_, err := tx.CreateBucketIfNotExists([]byte(handlers.RepoBucket))
-		if err != nil {
-			return err
-		}
-		_, err = tx.CreateBucketIfNotExists([]byte(handlers.MetaBucket))
-		return err
-	})
-	return err
-}
-
 // metrics provides functionality for monitoring the application status
 type metrics struct {
 	responseTimes *prometheus.SummaryVec
@@ -114,14 +96,17 @@ func (m metrics) instrument(path string, h http.HandlerFunc) (string, http.Handl
 }
 
 func main() {
+	flag.StringVar(&addr, "http", ":8000", "HTTP listen address")
+	flag.StringVar(&redisHost, "redis", "", "Address of Redis server")
 	flag.Parse()
 	if err := os.MkdirAll("_repos/src/github.com", 0755); err != nil && !os.IsExist(err) {
 		log.Fatal("ERROR: could not create repos dir: ", err)
 	}
 
 	// initialize database
-	if err := initDB(); err != nil {
-		log.Fatal("ERROR: could not open bolt db: ", err)
+	_, err := database.GetConnection(redisHost)
+	if err != nil {
+		log.Fatal("ERROR: could not connect to db: ", err)
 	}
 
 	m := setupMetrics()
@@ -137,6 +122,6 @@ func main() {
 
 	http.Handle("/metrics", promhttp.Handler())
 
-	log.Printf("Running on %s ...", *addr)
-	log.Fatal(http.ListenAndServe(*addr, nil))
+	log.Printf("Running on %s ...", addr)
+	log.Fatal(http.ListenAndServe(addr, nil))
 }