expanding options for databases. abstractions for database push/pull functions

4 files changed, 94 insertions, 30 deletions

diff --git a/cache.go b/cache.go
index 3a7886e..fb32e04 100644
--- a/cache.go
+++ b/cache.go
@@ -75,12 +75,7 @@ func refreshCache() {
 	confObj.Mu.Unlock()
 }
 
-// Pushes the registry's cache data to a local
-// database for safe keeping.
-func pushDatabase() error {
-	db := <-dbChan
-	dbChan <- db
-
+func (lvl dbLevel) push() error {
 	twtxtCache.Mu.RLock()
 	var dbBasket = &leveldb.Batch{}
 	for k, v := range twtxtCache.Users {
@@ -101,7 +96,7 @@ func pushDatabase() error {
 	}
 	remoteRegistries.Mu.RUnlock()
 
-	if err := db.Write(dbBasket, nil); err != nil {
+	if err := lvl.db.Write(dbBasket, nil); err != nil {
 		return err
 	}
 
@@ -112,11 +107,33 @@ func pushDatabase() error {
 	return nil
 }
 
+func (lite dbSqlite) push() error {
+
+	return nil
+}
+
+func (lite dbSqlite) pull() {
+
+}
+
+// Pushes the registry's cache data to a local
+// database for safe keeping.
+func pushDatabase() error {
+	db := <-dbChan
+	dbChan <- db
+
+	return db.push()
+}
+
 func pullDatabase() {
 	db := <-dbChan
 	dbChan <- db
+	db.pull()
+}
+
+func (lvl dbLevel) pull() {
 
-	iter := db.NewIterator(nil, nil)
+	iter := lvl.db.NewIterator(nil, nil)
 
 	for iter.Next() {
 		key := string(iter.Key())
diff --git a/getwtxt.yml b/getwtxt.yml
index 460ff4e..4c72454 100644
--- a/getwtxt.yml
+++ b/getwtxt.yml
@@ -22,7 +22,12 @@
 # This is the port that getwtxt will bind to.
 ListenPort: 9001
 
-# The location of the LevelDB database structure. Can be
+# The type of database you want to use. Currently,
+# the following are supported:
+#   leveldb
+DatabaseType: "leveldb"
+
+# The location of the database structure. Can be
 # a relative or absolute path.
 DatabasePath: "getwtxt.db"
 
diff --git a/init.go b/init.go
index ba3fdfc..076a7ca 100644
--- a/init.go
+++ b/init.go
@@ -1,6 +1,7 @@
 package main
 
 import (
+	"database/sql"
 	"fmt"
 	"html/template"
 	"log"
@@ -33,7 +34,7 @@ var closeLog = make(chan bool, 1)
 
 // used to transmit database pointer after
 // initialization
-var dbChan = make(chan *leveldb.DB, 1)
+var dbChan = make(chan dbase, 1)
 
 var tmpls *template.Template
 
@@ -136,6 +137,7 @@ func initConfig() {
 	confObj.Port = viper.GetInt("ListenPort")
 	confObj.LogFile = viper.GetString("LogFile")
 
+	confObj.DBType = strings.ToLower(viper.GetString("DatabaseType"))
 	confObj.DBPath = viper.GetString("DatabasePath")
 	log.Printf("Using database: %v\n", confObj.DBPath)
 
@@ -213,6 +215,7 @@ func rebindConfig() {
 	confObj.Mu.Lock()
 
 	confObj.LogFile = viper.GetString("LogFile")
+	confObj.DBType = strings.ToLower(viper.GetString("DatabaseType"))
 	confObj.DBPath = viper.GetString("DatabasePath")
 	confObj.StdoutLogging = viper.GetBool("StdoutLogging")
 	confObj.CacheInterval = viper.GetDuration("StatusFetchInterval")
@@ -235,9 +238,24 @@ func initTemplates() *template.Template {
 
 // Pull DB data into cache, if available.
 func initDatabase() {
+	var db dbase
+	var err error
+
 	confObj.Mu.RLock()
-	db, err := leveldb.OpenFile(confObj.DBPath, nil)
+	switch confObj.DBType {
+
+	case "leveldb":
+		var lvl *leveldb.DB
+		lvl, err = leveldb.OpenFile(confObj.DBPath, nil)
+		db = &dbLevel{db: lvl}
+
+	case "sqlite":
+		var lite *sql.DB
+		db = &dbSqlite{db: lite}
+
+	}
 	confObj.Mu.RUnlock()
+
 	if err != nil {
 		log.Fatalf("%v\n", err.Error())
 	}
@@ -259,11 +277,18 @@ func watchForInterrupt() {
 
 			log.Printf("\n\nCaught %v. Cleaning up ...\n", sigint)
 			confObj.Mu.RLock()
-
 			log.Printf("Closing database connection to %v...\n", confObj.DBPath)
+
 			db := <-dbChan
-			if err := db.Close(); err != nil {
-				log.Printf("%v\n", err.Error())
+
+			switch dbType := db.(type) {
+
+			case *dbLevel:
+				lvl := dbType
+				if err := lvl.db.Close(); err != nil {
+					log.Printf("%v\n", err.Error())
+				}
+
 			}
 
 			if !confObj.StdoutLogging {
diff --git a/types.go b/types.go
index 16f3c55..7e78ae0 100644
--- a/types.go
+++ b/types.go
@@ -1,8 +1,11 @@
 package main
 
 import (
+	"database/sql"
 	"sync"
 	"time"
+
+	"github.com/syndtr/goleveldb/leveldb"
 )
 
 // content-type consts
@@ -13,26 +16,40 @@ const cssutf8 = "text/css; charset=utf-8"
 // Configuration object definition
 type Configuration struct {
 	Mu            sync.RWMutex
-	Port          int           `json:"ListenPort"`
-	LogFile       string        `json:"LogFile"`
-	DBPath        string        `json:"DatabasePath"`
-	StdoutLogging bool          `json:"StdoutLogging"`
-	Version       string        `json:"-"`
-	CacheInterval time.Duration `json:"StatusFetchInterval"`
-	DBInterval    time.Duration `json:"DatabasePushInterval"`
-	LastCache     time.Time     `json:"-"`
-	LastPush      time.Time     `json:"-"`
-	Instance      `json:"Instance"`
+	Port          int           `yaml:"ListenPort"`
+	LogFile       string        `yaml:"LogFile"`
+	DBType        string        `yaml:"DatabaseType"`
+	DBPath        string        `yaml:"DatabasePath"`
+	StdoutLogging bool          `yaml:"StdoutLogging"`
+	Version       string        `yaml:"-"`
+	CacheInterval time.Duration `yaml:"StatusFetchInterval"`
+	DBInterval    time.Duration `yaml:"DatabasePushInterval"`
+	LastCache     time.Time     `yaml:"-"`
+	LastPush      time.Time     `yaml:"-"`
+	Instance      `yaml:"Instance"`
 }
 
 // Instance refers to this specific instance of getwtxt
 type Instance struct {
-	Vers  string `json:"-"`
-	Name  string `json:"Instance.SiteName"`
-	URL   string `json:"Instance.URL"`
-	Owner string `json:"Instance.OwnerName"`
-	Mail  string `json:"Instance.Email"`
-	Desc  string `json:"Instance.Description"`
+	Vers  string `yaml:"-"`
+	Name  string `yaml:"Instance.SiteName"`
+	URL   string `yaml:"Instance.URL"`
+	Owner string `yaml:"Instance.OwnerName"`
+	Mail  string `yaml:"Instance.Email"`
+	Desc  string `yaml:"Instance.Description"`
+}
+
+type dbLevel struct {
+	db *leveldb.DB
+}
+
+type dbSqlite struct {
+	db *sql.DB
+}
+
+type dbase interface {
+	push() error
+	pull()
 }
 
 // RemoteRegistries holds a list of remote registries to