First commit

driver/localDbDriver.go

@@ -0,0 +1,212 @@
+package driver
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"sync"
+
+	"github.com/google/uuid"
+	"github.com/jcelliott/lumber"
+)
+
+const Version = "1.0.1"
+const parentDir = "C:/local-go-db/"
+
+type (
+	Logger interface {
+		Fatal(string, ...interface{})
+		Error(string, ...interface{})
+		Info(string, ...interface{})
+		Warn(string, ...interface{})
+		Debug(string, ...interface{})
+		Trace(string, ...interface{})
+	}
+
+	Driver struct {
+		mutex   sync.Mutex
+		mutexes map[string]*sync.Mutex
+		dir     string
+		log     Logger
+	}
+)
+
+type Options struct {
+	Logger
+}
+
+type Data struct {
+	ID     string
+	Object interface{}
+}
+
+func NewConnection(dbName string, options *Options) (*Driver, error) {
+	if dbName == "" {
+		return nil, fmt.Errorf("Cannot create Nameless database - No name given")
+	}
+	dir := parentDir + dbName
+	dir = filepath.Clean(dir)
+
+	opts := Options{}
+	if options != nil {
+		opts = *options
+	}
+
+	if opts.Logger == nil {
+		opts.Logger = lumber.NewConsoleLogger((lumber.INFO))
+	}
+
+	driver := Driver{
+		dir:     dir,
+		mutexes: make(map[string]*sync.Mutex),
+		log:     opts.Logger,
+	}
+
+	if _, err := os.Stat(dir); err == nil {
+		opts.Logger.Debug("Using '%s' (database already exists)\n", dir)
+		return &driver, nil
+	}
+
+	opts.Logger.Debug("Creating the database at '%s'...\n", dir)
+	return &driver, os.MkdirAll(dir, 0755)
+}
+
+func (d *Driver) InsertOne(collection string, v interface{}) error {
+
+	if collection == "" {
+		return fmt.Errorf("Missing collection - no place to save record!")
+	}
+
+	// Create new uuid for object and append object to database
+
+	var data Data
+	data.ID = uuid.New().String()
+	data.Object = v
+
+	mutex := d.getOrCreateMutex(collection)
+	mutex.Lock()
+	defer mutex.Unlock()
+
+	dir := filepath.Join(d.dir, collection)
+	fnlPath := filepath.Join(dir, data.ID+".json")
+	tmpPath := fnlPath + ".tmp"
+
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return err
+	}
+
+	b, err := json.MarshalIndent(data, "", "\t")
+	if err != nil {
+		return err
+	}
+
+	b = append(b, byte('\n'))
+
+	if err := ioutil.WriteFile(tmpPath, b, 0644); err != nil {
+		return err
+	}
+
+	return os.Rename(tmpPath, fnlPath)
+}
+
+func (d *Driver) InsertMany(collection, resource string) {
+
+}
+
+func (d *Driver) FindOne(collection, id string) (interface{}, error) {
+	if collection == "" {
+		return nil, fmt.Errorf("Missing collection - unable to read!")
+	}
+
+	record := filepath.Join(d.dir, collection, id)
+
+	if _, err := stat(record); err != nil {
+		fmt.Println(err)
+		return nil, fmt.Errorf("The object you're searching for cannot be found")
+	}
+
+	b, err := ioutil.ReadFile(record + ".json")
+	if err != nil {
+		return nil, err
+	}
+	var v Data
+	json.Unmarshal(b, &v)
+
+	return v, nil
+}
+
+func (d *Driver) FindAll(collection string) ([]string, error) {
+
+	if collection == "" {
+		return nil, fmt.Errorf("Missing collection - unable to read!")
+	}
+	dir := filepath.Join(d.dir, collection)
+
+	if _, err := stat(dir); err != nil {
+		return nil, err
+	}
+
+	files, _ := ioutil.ReadDir(dir)
+
+	var records []string
+
+	for _, file := range files {
+		b, err := ioutil.ReadFile(filepath.Join(dir, file.Name()))
+		if err != nil {
+			return nil, err
+		}
+
+		records = append(records, string(b))
+	}
+	return records, nil
+}
+
+func (d *Driver) Delete(collection, id string) error {
+
+	path := filepath.Join(collection, id)
+	mutex := d.getOrCreateMutex(collection)
+	mutex.Lock()
+	defer mutex.Unlock()
+
+	dir := filepath.Join(d.dir, path)
+
+	switch fi, err := stat(dir); {
+	case fi == nil, err != nil:
+		return fmt.Errorf("Unable to find file or directory name %v\n", path)
+
+	case fi.Mode().IsDir():
+		return os.RemoveAll(dir)
+
+	case fi.Mode().IsRegular():
+		return os.RemoveAll(dir + ".json")
+	}
+	return nil
+}
+
+func (d *Driver) getOrCreateMutex(collection string) *sync.Mutex {
+
+	d.mutex.Lock()
+	defer d.mutex.Unlock()
+	m, ok := d.mutexes[collection]
+
+	if !ok {
+		m = &sync.Mutex{}
+		d.mutexes[collection] = m
+	}
+
+	return m
+}
+
+func stat(path string) (fi os.FileInfo, err error) {
+	if fi, err = os.Stat(path); os.IsNotExist(err) {
+		fi, err = os.Stat(path + ".json")
+	}
+	return
+}
+
+type User struct {
+	Name string
+	Age  json.Number
+}