Preparatory work to move the store into a different service

server/main/main.go

@@ -21,6 +21,7 @@ import (
 )
 
 var config Configuration
+var store *SQLStore
 
 // WebsocketMsg is send on block changes
 type WebsocketMsg struct {
@@ -64,9 +65,9 @@ func handleGetBlocks(w http.ResponseWriter, r *http.Request) {
 
 	var blocks []string
 	if len(blockType) > 0 {
-		blocks = getBlocksWithParentAndType(parentID, blockType)
+		blocks = store.getBlocksWithParentAndType(parentID, blockType)
 	} else {
-		blocks = getBlocksWithParent(parentID)
+		blocks = store.getBlocksWithParent(parentID)
 	}
 	log.Printf("GetBlocks parentID: %s, %d result(s)", parentID, len(blocks))
 	response := `[` + strings.Join(blocks[:], ",") + `]`
@@ -127,7 +128,7 @@ func handlePostBlocks(w http.ResponseWriter, r *http.Request) {
 			return
 		}
 
-		insertBlock(block, string(jsonBytes))
+		store.insertBlock(block, string(jsonBytes))
 	}
 
 	broadcastBlockChangeToWebsocketClients(blockIDsToNotify)
@@ -142,13 +143,13 @@ func handleDeleteBlock(w http.ResponseWriter, r *http.Request) {
 
 	var blockIDsToNotify = []string{blockID}
 
-	parentID := getParentID(blockID)
+	parentID := store.getParentID(blockID)
 
 	if len(parentID) > 0 {
 		blockIDsToNotify = append(blockIDsToNotify, parentID)
 	}
 
-	deleteBlock(blockID)
+	store.deleteBlock(blockID)
 
 	broadcastBlockChangeToWebsocketClients(blockIDsToNotify)
 
@@ -160,7 +161,7 @@ func handleGetSubTree(w http.ResponseWriter, r *http.Request) {
 	vars := mux.Vars(r)
 	blockID := vars["blockID"]
 
-	blocks := getSubTree(blockID)
+	blocks := store.getSubTree(blockID)
 
 	log.Printf("GetSubTree blockID: %s, %d result(s)", blockID, len(blocks))
 	response := `[` + strings.Join(blocks[:], ",") + `]`
@@ -168,7 +169,7 @@ func handleGetSubTree(w http.ResponseWriter, r *http.Request) {
 }
 
 func handleExport(w http.ResponseWriter, r *http.Request) {
-	blocks := getAllBlocks()
+	blocks := store.getAllBlocks()
 
 	log.Printf("EXPORT Blocks, %d result(s)", len(blocks))
 	response := `[` + strings.Join(blocks[:], ",") + `]`
@@ -191,25 +192,24 @@ func handleImport(w http.ResponseWriter, r *http.Request) {
 		}
 	}()
 
-	var blockMaps []map[string]interface{}
+	var blocks []Block
-	err = json.Unmarshal([]byte(requestBody), &blockMaps)
+	err = json.Unmarshal([]byte(requestBody), &blocks)
 	if err != nil {
 		errorResponse(w, http.StatusInternalServerError, ``)
 		return
 	}
 
-	for _, blockMap := range blockMaps {
+	for _, block := range blocks {
-		jsonBytes, err := json.Marshal(blockMap)
+		jsonBytes, err := json.Marshal(block)
 		if err != nil {
 			errorResponse(w, http.StatusInternalServerError, `{}`)
 			return
 		}
 
-		block := blockFromMap(blockMap)
+		store.insertBlock(block, string(jsonBytes))
-		insertBlock(block, string(jsonBytes))
 	}
 
-	log.Printf("IMPORT Blocks %d block(s)", len(blockMaps))
+	log.Printf("IMPORT Blocks %d block(s)", len(blocks))
 	jsonResponse(w, http.StatusOK, "{}")
 }
 
@@ -434,7 +434,12 @@ func main() {
 
 	http.Handle("/", r)
 
-	connectDatabase(config.DBType, config.DBConfigString)
+	var err error
+	store, err = NewSQLStore(config.DBType, config.DBConfigString)
+	if err != nil {
+		log.Fatal("Unable to start the database", err)
+		panic(err)
+	}
 
 	// Ctrl+C handling
 	handler := make(chan os.Signal, 1)

server/main/octoDatabase.go

@@ -10,25 +10,38 @@ import (
 	_ "github.com/mattn/go-sqlite3"
 )
 
-var db *sql.DB
+type SQLStore struct {
+	db     *sql.DB
+	dbType string
+}
 
-func connectDatabase(dbType string, connectionString string) {
+func NewSQLStore(dbType, connectionString string) (*SQLStore, error) {
 	log.Println("connectDatabase")
 	var err error
 
-	db, err = sql.Open(dbType, connectionString)
+	db, err := sql.Open(dbType, connectionString)
 	if err != nil {
 		log.Fatal("connectDatabase: ", err)
-		panic(err)
+		return nil, err
 	}
 
 	err = db.Ping()
 	if err != nil {
 		log.Println(`Database Ping failed`)
-		panic(err)
+		return nil, err
 	}
 
-	createTablesIfNotExists(dbType)
+	store := &SQLStore{
+		db:     db,
+		dbType: dbType,
+	}
+
+	err = store.createTablesIfNotExists()
+	if err != nil {
+		log.Println(`Table creation failed`)
+		return nil, err
+	}
+	return store, nil
 }
 
 // Block is the basic data unit
@@ -41,11 +54,11 @@ type Block struct {
 	DeleteAt int64  `json:"deleteAt"`
 }
 
-func createTablesIfNotExists(dbType string) {
+func (s *SQLStore) createTablesIfNotExists() error {
 	// TODO: Add update_by with the user's ID
 	// TODO: Consolidate insert_at and update_at, decide if the server of DB should set it
 	var query string
-	if dbType == "sqlite3" {
+	if s.dbType == "sqlite3" {
 		query = `CREATE TABLE IF NOT EXISTS blocks (
 			id VARCHAR(36),
 			insert_at DATETIME NOT NULL DEFAULT current_timestamp,
@@ -71,12 +84,13 @@ func createTablesIfNotExists(dbType string) {
 		);`
 	}
 
-	_, err := db.Exec(query)
+	_, err := s.db.Exec(query)
 	if err != nil {
 		log.Fatal("createTablesIfNotExists: ", err)
-		panic(err)
+		return err
 	}
-	log.Printf("createTablesIfNotExists(%s)", dbType)
+	log.Printf("createTablesIfNotExists(%s)", s.dbType)
+	return nil
 }
 
 func blockFromMap(m map[string]interface{}) Block {
@@ -103,7 +117,7 @@ func blockFromMap(m map[string]interface{}) Block {
 	return b
 }
 
-func getBlocksWithParentAndType(parentID string, blockType string) []string {
+func (s *SQLStore) getBlocksWithParentAndType(parentID string, blockType string) []string {
 	query := `WITH latest AS
 		(
 			SELECT * FROM
@@ -120,7 +134,7 @@ func getBlocksWithParentAndType(parentID string, blockType string) []string {
 		FROM latest
 		WHERE delete_at = 0 and parent_id = $1 and type = $2`
 
-	rows, err := db.Query(query, parentID, blockType)
+	rows, err := s.db.Query(query, parentID, blockType)
 	if err != nil {
 		log.Printf(`getBlocksWithParentAndType ERROR: %v`, err)
 		panic(err)
@@ -129,7 +143,7 @@ func getBlocksWithParentAndType(parentID string, blockType string) []string {
 	return blocksFromRows(rows)
 }
 
-func getBlocksWithParent(parentID string) []string {
+func (s *SQLStore) getBlocksWithParent(parentID string) []string {
 	query := `WITH latest AS
 		(
 			SELECT * FROM
@@ -146,7 +160,7 @@ func getBlocksWithParent(parentID string) []string {
 		FROM latest
 		WHERE delete_at = 0 and parent_id = $1`
 
-	rows, err := db.Query(query, parentID)
+	rows, err := s.db.Query(query, parentID)
 	if err != nil {
 		log.Printf(`getBlocksWithParent ERROR: %v`, err)
 		panic(err)
@@ -155,7 +169,7 @@ func getBlocksWithParent(parentID string) []string {
 	return blocksFromRows(rows)
 }
 
-func getSubTree(blockID string) []string {
+func (s *SQLStore) getSubTree(blockID string) []string {
 	query := `WITH latest AS
 	(
 		SELECT * FROM
@@ -174,7 +188,7 @@ func getSubTree(blockID string) []string {
 		AND (id = $1
 			OR parent_id = $1)`
 
-	rows, err := db.Query(query, blockID)
+	rows, err := s.db.Query(query, blockID)
 	if err != nil {
 		log.Printf(`getSubTree ERROR: %v`, err)
 		panic(err)
@@ -183,7 +197,7 @@ func getSubTree(blockID string) []string {
 	return blocksFromRows(rows)
 }
 
-func getAllBlocks() []string {
+func (s *SQLStore) getAllBlocks() []string {
 	query := `WITH latest AS
 	(
 		SELECT * FROM
@@ -200,7 +214,7 @@ func getAllBlocks() []string {
 	FROM latest
 	WHERE delete_at = 0`
 
-	rows, err := db.Query(query)
+	rows, err := s.db.Query(query)
 	if err != nil {
 		log.Printf(`getAllBlocks ERROR: %v`, err)
 		panic(err)
@@ -229,7 +243,7 @@ func blocksFromRows(rows *sql.Rows) []string {
 	return results
 }
 
-func getParentID(blockID string) string {
+func (s *SQLStore) getParentID(blockID string) string {
 	statement :=
 		`WITH latest AS
 		(
@@ -248,7 +262,7 @@ func getParentID(blockID string) string {
 		WHERE delete_at = 0
 			AND id = $1`
 
-	row := db.QueryRow(statement, blockID)
+	row := s.db.QueryRow(statement, blockID)
 
 	var parentID string
 	err := row.Scan(&parentID)
@@ -259,19 +273,19 @@ func getParentID(blockID string) string {
 	return parentID
 }
 
-func insertBlock(block Block, json string) {
+func (s *SQLStore) insertBlock(block Block, json string) {
 	statement := `INSERT INTO blocks(id, parent_id, type, json, create_at, update_at, delete_at) VALUES($1, $2, $3, $4, $5, $6, $7)`
-	_, err := db.Exec(statement, block.ID, block.ParentID, block.Type, json, block.CreateAt, block.UpdateAt, block.DeleteAt)
+	_, err := s.db.Exec(statement, block.ID, block.ParentID, block.Type, json, block.CreateAt, block.UpdateAt, block.DeleteAt)
 	if err != nil {
 		panic(err)
 	}
 }
 
-func deleteBlock(blockID string) {
+func (s *SQLStore) deleteBlock(blockID string) {
 	now := time.Now().Unix()
 	json := fmt.Sprintf(`{"id":"%s","updateAt":%d,"deleteAt":%d}`, blockID, now, now)
 	statement := `INSERT INTO blocks(id, json, update_at, delete_at) VALUES($1, $2, $3, $4)`
-	_, err := db.Exec(statement, blockID, json, now, now)
+	_, err := s.db.Exec(statement, blockID, json, now, now)
 	if err != nil {
 		panic(err)
 	}