commit 84a7206c08ce2f963d2ddb9652cc2f6eb55ce676
Author: heimoshuiyu <heimoshuiyu@gmail.com>
Date:   Fri May 21 01:00:58 2021 +0800

    后端初步完成

diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..c87cde8
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,5 @@
+module msw-open-music
+
+go 1.16
+
+require github.com/mattn/go-sqlite3 v1.14.7 // indirect
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..96ff824
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,2 @@
+github.com/mattn/go-sqlite3 v1.14.7 h1:fxWBnXkxfM6sRiuH3bqJ4CfzZojMOLVc0UTsTglEghA=
+github.com/mattn/go-sqlite3 v1.14.7/go.mod h1:NyWgC/yNuGj7Q9rpYnZvas74GogHl5/Z4A/KQRfk6bU=
diff --git a/internal/pkg/api/api.go b/internal/pkg/api/api.go
new file mode 100644
index 0000000..33a613f
--- /dev/null
+++ b/internal/pkg/api/api.go
@@ -0,0 +1,300 @@
+package api
+
+import (
+	"encoding/json"
+	"errors"
+	"io"
+	"log"
+	"msw-open-music/internal/pkg/database"
+	"net/http"
+	"os"
+)
+
+type API struct {
+	Db *database.Database
+	Server http.Server
+	token string
+}
+
+type Status struct {
+	Status string `json:"status,omitempty"`
+}
+var ok Status = Status{
+	Status: "OK",
+}
+
+type WalkRequest struct {
+	Token string `json:"token"`
+	Root string `json:"root"`
+	Pattern []string `json:"pattern"`
+}
+
+type ResetRequest struct {
+	Token string `json:"token"`
+}
+
+type SearchFilesRequest struct {
+	Filename string `json:"filename"`
+	Limit int64 `json:"limit"`
+	Offest int64 `json:"offest"`
+}
+
+type SearchFoldersRequest struct {
+	Foldername string `json:"foldername"`
+	Limit int64 `json:"limit"`
+	Offest int64 `json:"offest"`
+}
+
+type SearchFilesRespond struct {
+	Files []database.File `json:"files"`
+}
+
+type SearchFoldersRespond struct {
+	Folders []database.Folder `json:"folders"`
+}
+
+func (api *API) CheckToken(token string) (error) {
+	if token != api.token {
+		return errors.New("token not matched")
+	}
+	return nil
+}
+
+func (api *API) HandleTokenNotMatch(w http.ResponseWriter, r *http.Request) {
+	api.HandleErrorStringCode(w, r, "token not match", 403)
+}
+
+func (api *API) HandleError(w http.ResponseWriter, r *http.Request, err error) {
+	api.HandleErrorString(w, r, err.Error())
+}
+
+func (api *API) HandleErrorCode(w http.ResponseWriter, r *http.Request, err error, code int) {
+	api.HandleErrorStringCode(w, r, err.Error(), code)
+}
+
+func (api *API) HandleErrorString(w http.ResponseWriter, r *http.Request, errorString string) {
+	api.HandleErrorStringCode(w, r, errorString, 500)
+}
+
+func (api *API) HandleErrorStringCode(w http.ResponseWriter, r *http.Request, errorString string, code int) {
+	log.Println("Handle Error", errorString)
+	errStatus := &Status{
+		Status: errorString,
+	}
+	w.WriteHeader(code)
+	json.NewEncoder(w).Encode(errStatus)
+}
+
+func (api *API) HandleReset(w http.ResponseWriter, r *http.Request) {
+	resetRequest := &ResetRequest{}
+	err := json.NewDecoder(r.Body).Decode(resetRequest)
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+
+	// check token
+	err = api.CheckToken(resetRequest.Token)
+	if err != nil {
+		api.HandleTokenNotMatch(w, r)
+		return
+	}
+
+	// reset
+	err = api.Db.ResetFiles()
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+	err = api.Db.ResetFolder()
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+
+	api.HandleStatus(w, r, "Database reseted")
+}
+
+func (api *API) HandleWalk(w http.ResponseWriter, r *http.Request) {
+	walkRequest := &WalkRequest{}
+	err := json.NewDecoder(r.Body).Decode(walkRequest)
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+
+	// check token match
+	err = api.CheckToken(walkRequest.Token)
+	if err != nil {
+		api.HandleTokenNotMatch(w, r)
+		return
+	}
+
+	// check root empty
+	if walkRequest.Root == "" {
+		api.HandleErrorString(w, r, `key "root" can't be empty`)
+		return
+	}
+
+	// check pattern empty
+	if len(walkRequest.Pattern) == 0 {
+		api.HandleErrorString(w, r, `"[]pattern" can't be empty`)
+		return
+	}
+
+	// walk
+	err = api.Db.Walk(walkRequest.Root, walkRequest.Pattern)
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+
+	api.HandleStatus(w, r, "Database udpated")
+}
+
+func (api *API) HandleOK(w http.ResponseWriter, r *http.Request) {
+	json.NewEncoder(w).Encode(&ok)
+}
+
+func (api *API) HandleStatus(w http.ResponseWriter, r *http.Request, status string) {
+	s := &Status{
+		Status: status,
+	}
+
+	json.NewEncoder(w).Encode(s)
+}
+
+func (api *API) HandleSearchFiles(w http.ResponseWriter, r *http.Request) {
+	searchFilesRequest := &SearchFilesRequest{}
+	err := json.NewDecoder(r.Body).Decode(searchFilesRequest)
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+
+	// check empty
+	if searchFilesRequest.Filename == "" {
+		api.HandleErrorString(w, r, `"filename" can't be empty`)
+		return
+	}
+	if searchFilesRequest.Limit == 0 {
+		api.HandleErrorString(w, r, `"limit" can't be zero`)
+		return
+	}
+
+	searchFilesRespond := &SearchFilesRespond{}
+
+	searchFilesRespond.Files, err = api.Db.SearchFiles(searchFilesRequest.Filename, searchFilesRequest.Limit, searchFilesRequest.Limit)
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+
+	json.NewEncoder(w).Encode(searchFilesRespond)
+}
+
+func (api *API) HandleSearchFolders(w http.ResponseWriter, r *http.Request) {
+	searchFoldersRequest := &SearchFoldersRequest{}
+	err := json.NewDecoder(r.Body).Decode(searchFoldersRequest)
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+
+	// check empty
+	if searchFoldersRequest.Foldername == "" {
+		api.HandleErrorString(w, r, `"foldername" can't be empty`)
+		return
+	}
+	if searchFoldersRequest.Limit == 0 {
+		api.HandleErrorString(w, r, `"limit" can't be zero`)
+		return
+	}
+
+	searchFoldersRespond := &SearchFoldersRespond{}
+
+	searchFoldersRespond.Folders, err = api.Db.SearchFolders(searchFoldersRequest.Foldername, searchFoldersRequest.Limit, searchFoldersRequest.Limit)
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+
+	json.NewEncoder(w).Encode(searchFoldersRespond)
+}
+
+type GetFileRequest struct {
+	ID int64 `json:"id"`
+}
+
+func (api *API) HandleGetFile(w http.ResponseWriter, r *http.Request) {
+	getFilesRequest := &GetFileRequest{
+		ID: -1,
+	}
+
+	err := json.NewDecoder(r.Body).Decode(getFilesRequest)
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+
+	// check empty
+	if getFilesRequest.ID < 0 {
+		api.HandleErrorString(w, r, `"id" can't be none or negative`)
+		return
+	}
+
+	file, err := api.Db.GetFile(getFilesRequest.ID)
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+
+	path, err := file.Path()
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+
+	src, err := os.Open(path)
+	if err != nil {
+		api.HandleError(w, r, err)
+		return
+	}
+	defer src.Close()
+	io.Copy(w, src)
+}
+
+func NewAPI(dbName string, Addr string) (*API, error) {
+	var err error
+
+	db, err := database.NewDatabase(dbName)
+	if err != nil {
+		return nil, err
+	}
+
+	mux := http.NewServeMux()
+	apiMux := http.NewServeMux()
+
+	api := &API{
+		Db: db,
+		Server: http.Server{
+			Addr: Addr,
+			Handler: mux,
+		},
+	}
+
+	// mount api
+	apiMux.HandleFunc("/hello", api.HandleOK)
+	apiMux.HandleFunc("/get_file", api.HandleGetFile)
+	apiMux.HandleFunc("/search_files", api.HandleSearchFiles)
+	apiMux.HandleFunc("/search_folders", api.HandleSearchFolders)
+	// below needs token
+	apiMux.HandleFunc("/walk", api.HandleWalk)
+	apiMux.HandleFunc("/reset", api.HandleReset)
+
+	mux.Handle("/api/v1/", http.StripPrefix("/api/v1", apiMux))
+
+	api.token = "pwd"
+
+	return api, nil
+}
diff --git a/internal/pkg/api/api_test.go b/internal/pkg/api/api_test.go
new file mode 100644
index 0000000..c1a11ba
--- /dev/null
+++ b/internal/pkg/api/api_test.go
@@ -0,0 +1,11 @@
+package api
+
+import "testing"
+
+func TestAPI(t *testing.T) {
+	api, err := NewAPI("/tmp/test.sqlite3", ":8080")
+	if err != nil {
+		t.Fatal(err.Error())
+	}
+	t.Fatal(api.Server.ListenAndServe())
+}
diff --git a/internal/pkg/database/database.go b/internal/pkg/database/database.go
new file mode 100644
index 0000000..1c7bd68
--- /dev/null
+++ b/internal/pkg/database/database.go
@@ -0,0 +1,349 @@
+package database
+
+import (
+	"database/sql"
+	"errors"
+	"log"
+	"os"
+	"path/filepath"
+
+	_ "github.com/mattn/go-sqlite3"
+)
+
+var initFilesTableQuery = `CREATE TABLE IF NOT EXISTS files (
+	id INTEGER PRIMARY KEY,
+	folder_id INTEGER NOT NULL,
+	filename TEXT NOT NULL
+);`
+var initFoldersTableQuery = `CREATE TABLE IF NOT EXISTS folders (
+	id INTEGER PRIMARY KEY,
+	folder TEXT NOT NULL,
+	foldername TEXT NOT NULL
+);`
+var insertFolderQuery = `INSERT INTO folders (folder, foldername) VALUES (?, ?);`
+var findFolderQuery = `SELECT id FROM folders WHERE folder = ? LIMIT 1;`
+var insertFileQuery = `INSERT INTO files (folder_id, filename) VALUES (?, ?);`
+var searchFilesQuery = `SELECT files.id, files.folder_id, files.filename, folders.foldername FROM files JOIN folders ON files.folder_id = folders.id WHERE filename LIKE ? LIMIT ? OFFSET ?;`
+var getFolderQuery = `SELECT folder FROM folders WHERE id = ? LIMIT 1;`
+var dropFilesQuery = `DROP TABLE files;`
+var dropFolderQuery = `DROP TABLE folders;`
+var getFileQuery = `SELECT files.id, files.folder_id, files.filename, folders.foldername FROM files JOIN folders ON files.folder_id = folders.id WHERE files.id = ? LIMIT 1;`
+var searchFoldersQuery = `SELECT id, folder, foldername FROM folders WHERE foldername LIKE ? LIMIT ? OFFSET ?;`
+
+type Database struct {
+	sqlConn *sql.DB
+	stmt *Stmt
+}
+
+type Stmt struct {
+	initFilesTable *sql.Stmt
+	initFoldersTable *sql.Stmt
+	insertFolder *sql.Stmt
+	insertFile *sql.Stmt
+	findFolder *sql.Stmt
+	searchFiles *sql.Stmt
+	getFolder *sql.Stmt
+	dropFiles *sql.Stmt
+	dropFolder *sql.Stmt
+	getFile *sql.Stmt
+	searchFolders *sql.Stmt
+}
+
+type File struct {
+	Db *Database `json:"-"`
+	ID int64 `json:"id"`
+	Folder_id int64 `json:"folder_id"`
+	Foldername string `json:"foldername"`
+	Filename string `json:"filename"`
+}
+
+type Folder struct {
+	Db *Database `json:"-"`
+	ID int64 `json:"id"`
+	Folder string `json:"folder"`
+	Foldername string `json:"foldername"`
+}
+
+func (database *Database) SearchFolders(foldername string, limit int64, offset int64) ([]Folder, error) {
+	rows, err := database.stmt.searchFolders.Query("%"+foldername+"%", limit, offset)
+	if err != nil {
+		return nil, errors.New("Error searching folders at query " + err.Error())
+	}
+	defer rows.Close()
+	folders := make([]Folder, 0)
+	for rows.Next() {
+		folder := Folder{
+			Db: database,
+		}
+		err = rows.Scan(&folder.ID, &folder.Folder, &folder.Foldername)
+		if err != nil {
+			return nil, errors.New("Error scanning SearchFolders" + err.Error())
+		}
+		folders = append(folders, folder)
+	}
+	return folders, nil
+}
+
+func (database *Database) GetFile(id int64) (*File, error) {
+	file := &File{
+		Db: database,
+	}
+	err := database.stmt.getFile.QueryRow(id).Scan(&file.ID, &file.Folder_id, &file.Filename, &file.Foldername)
+	if err != nil {
+		return nil, err
+	}
+	return file, nil
+}
+
+func (database *Database) ResetFiles() (error) {
+	var err error
+	_, err = database.stmt.dropFiles.Exec()
+	if err != nil {
+		return err
+	}
+	_, err = database.stmt.initFilesTable.Exec()
+	if err != nil {
+		return err
+	}
+	return err
+}
+
+func (database *Database) ResetFolder() (error) {
+	var err error
+	_, err = database.stmt.dropFolder.Exec()
+	if err != nil {
+		return err
+	}
+	_, err = database.stmt.initFoldersTable.Exec()
+	if err != nil {
+		return err
+	}
+	return err
+}
+
+func (database *Database) Walk(root string, pattern []string) (error) {
+	patternDict := make(map[string]bool)
+	for _, v := range pattern {
+		patternDict[v] = true
+	}
+	log.Println(patternDict)
+	return filepath.Walk(root, func (path string, info os.FileInfo, err error) (error) {
+		if err != nil {
+			return err
+		}
+
+		if info.IsDir() {
+			return nil
+		}
+
+		// check pattern
+		ext := filepath.Ext(info.Name())
+		if _, ok := patternDict[ext]; !ok {
+			log.Println("False", ext, info.Name())
+			return nil
+		}
+		log.Println("True", ext, info.Name())
+
+		// insert file, folder will aut created
+		err = database.Insert(path)
+		if err != nil {
+			return err
+		}
+		return nil
+	})
+}
+
+func (f *File) Path() (string, error) {
+	folder, err := f.Db.GetFolder(f.Folder_id)
+	if err != nil {
+		return "", err
+	}
+	return filepath.Join(folder.Folder, f.Filename), nil
+}
+
+func (database *Database) GetFolder(folderId int64) (*Folder, error) {
+	folder := &Folder{
+		Db: database,
+	}
+	err := database.stmt.getFolder.QueryRow(folderId).Scan(&folder.Folder)
+	if err != nil {
+		return nil, err
+	}
+	return folder, nil
+}
+
+func (database *Database) SearchFiles(filename string, limit int64, offset int64) ([]File, error) {
+	rows, err := database.stmt.searchFiles.Query("%"+filename+"%", limit, offset)
+	if err != nil {
+		return nil, errors.New("Error searching files at query " + err.Error())
+	}
+	defer rows.Close()
+	files := make([]File, 0)
+	for rows.Next() {
+		var file File = File{
+			Db: database,
+		}
+		err = rows.Scan(&file.ID, &file.Folder_id, &file.Filename, &file.Foldername)
+		if err != nil {
+			return nil, errors.New("Error scanning SearchFiles " + err.Error())
+		}
+		files = append(files, file)
+	}
+	if err = rows.Err(); err != nil {
+		return nil, errors.New("Error scanning SearchFiles exit without full result" + err.Error())
+	}
+	return files, nil
+}
+
+func (database *Database) FindFolder(folder string) (int64, error) {
+	var id int64
+	err := database.stmt.findFolder.QueryRow(folder).Scan(&id)
+	if err != nil {
+		return 0, err
+	}
+	return id, nil
+}
+
+func (database *Database) InsertFolder(folder string) (int64, error) {
+	result, err := database.stmt.insertFolder.Exec(folder, filepath.Base(folder))
+	if err != nil {
+		return 0, err
+	}
+	lastInsertId, err := result.LastInsertId()
+	if err != nil {
+		return 0, err
+	}
+	return lastInsertId, nil
+}
+
+func (database *Database) InsertFile(folderId int64, filename string) (error) {
+	_, err := database.stmt.insertFile.Exec(folderId, filename)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func (database *Database) Insert(path string) (error) {
+	folder, filename := filepath.Split(path)
+	folderId, err := database.FindFolder(folder)
+	if err != nil {
+		folderId, err = database.InsertFolder(folder)
+		if err != nil {
+			return err
+		}
+	}
+	err = database.InsertFile(folderId, filename)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func NewPreparedStatement(sqlConn *sql.DB) (*Stmt, error) {
+	var err error
+
+	stmt := &Stmt{}
+
+	// init files table
+	stmt.initFilesTable, err = sqlConn.Prepare(initFilesTableQuery)
+	if err != nil {
+		return nil, err
+	}
+
+	// init folders table
+	stmt.initFoldersTable, err = sqlConn.Prepare(initFoldersTableQuery)
+	if err != nil {
+		return nil, err
+	}
+
+	// run init statement
+	_, err = stmt.initFilesTable.Exec()
+	if err != nil {
+		return nil, err
+	}
+	_, err = stmt.initFoldersTable.Exec()
+	if err != nil {
+		return nil, err
+	}
+
+	// init insert folder statement
+	stmt.insertFolder, err = sqlConn.Prepare(insertFolderQuery)
+	if err != nil {
+		return nil, err
+	}
+
+	// init findFolder statement
+	stmt.findFolder, err = sqlConn.Prepare(findFolderQuery)
+	if err != nil {
+		return nil, err
+	}
+
+	// init insertFile stmt
+	stmt.insertFile, err = sqlConn.Prepare(insertFileQuery)
+	if err != nil {
+		return nil, err
+	}
+
+	// init searchFile stmt
+	stmt.searchFiles, err = sqlConn.Prepare(searchFilesQuery)
+	if err != nil {
+		return nil, err
+	}
+
+	// init getFolder stmt
+	stmt.getFolder, err = sqlConn.Prepare(getFolderQuery)
+	if err != nil {
+		return nil, err
+	}
+
+	// init dropFolder stmt
+	stmt.dropFolder, err = sqlConn.Prepare(dropFolderQuery)
+	if err != nil {
+		return nil, err
+	}
+
+	// init dropFiles stmt
+	stmt.dropFiles, err = sqlConn.Prepare(dropFilesQuery)
+	if err != nil {
+		return nil, err
+	}
+
+	// init getFile stmt
+	stmt.getFile, err = sqlConn.Prepare(getFileQuery)
+	if err != nil {
+		return nil, err
+	}
+
+	// init searchFolder stmt
+	stmt.searchFolders, err = sqlConn.Prepare(searchFoldersQuery)
+	if err != nil {
+		return nil, err
+	}
+
+	return stmt, err
+}
+
+func NewDatabase(dbName string) (*Database, error) {
+	var err error
+
+	// open database
+	sqlConn, err := sql.Open("sqlite3", dbName)
+	if err != nil {
+		return nil, err
+	}
+
+	// prepare statement
+	stmt, err := NewPreparedStatement(sqlConn)
+	if err != nil {
+		return nil, err
+	}
+
+	// new database
+	database := &Database{
+		sqlConn: sqlConn,
+		stmt: stmt,
+	}
+
+	return database, nil
+}
diff --git a/internal/pkg/database/database_test.go b/internal/pkg/database/database_test.go
new file mode 100644
index 0000000..fe1778c
--- /dev/null
+++ b/internal/pkg/database/database_test.go
@@ -0,0 +1,55 @@
+package database
+
+import (
+	"testing"
+)
+
+func TestDatabase(t *testing.T) {
+	db, err := NewDatabase("/tmp/test.sqlite3")
+	if err != nil {
+		t.Fatal("Error creating database" + err.Error())
+	}
+	t.Log("database open successfully")
+
+	_, err = db.InsertFolder("testfolder")
+	if err != nil {
+		t.Fatal(err.Error())
+	}
+	t.Log("insertFolders successfully")
+
+	id, err := db.FindFolder("testfolder")
+	if err != nil {
+		t.Fatal(err.Error())
+	}
+	t.Log("folder found", id)
+
+	err = db.Insert("/home/hmsy/go/bin/typora-image-ffmpeg")
+	if err != nil {
+		t.Fatal(err.Error())
+	}
+
+	files, err := db.SearchFiles("ffmpeg", 100, 0)
+	if err != nil {
+		t.Fatal(err.Error())
+	}
+	t.Log(files)
+
+	file := files[0]
+	t.Log(file.Path())
+
+	err = db.Walk("/home/hmsy/dsa/")
+	if err != nil {
+		t.Fatal(err.Error())
+	}
+
+	//err = db.ResetFiles()
+	//if err != nil {
+	//	t.Fatal(err.Error())
+	//}
+
+	//err = db.ResetFolder()
+	//if err != nil {
+	//	t.Fatal(err.Error())
+	//}
+
+}