Initial Commit

store/user.go

@@ -0,0 +1,115 @@
+package store
+
+import (
+	"encoding/json"
+	"errors"
+
+	"github.com/dgraph-io/badger/v4"
+	"github.com/google/uuid"
+)
+
+type User struct {
+	ID       string
+	Name     string
+	Email    string
+	Password string
+}
+
+const (
+	userPrefix     = "user:"
+	emailIndexPref = "email:"
+)
+
+var (
+	ErrEmailExists = errors.New("email already registered")
+)
+
+func CreateUser(name, email, password string) (*User, error) {
+	// Enforce uniqueness
+	if _, err := findUserIDByEmail(email); err == nil {
+		return nil, ErrEmailExists
+	}
+
+	user := &User{
+		ID:       uuid.NewString(),
+		Name:     name,
+		Email:    email,
+		Password: password,
+	}
+	data, err := json.Marshal(user)
+	if err != nil {
+		return nil, err
+	}
+
+	err = GetDB().Update(func(txn *badger.Txn) error {
+		if err := txn.Set([]byte(userPrefix+user.ID), data); err != nil {
+			return err
+		}
+		return txn.Set([]byte(emailIndexPref+email), []byte(user.ID))
+	})
+
+	return user, err
+}
+
+func FindUserByID(id string) (*User, error) {
+	var user User
+	err := GetDB().View(func(txn *badger.Txn) error {
+		item, err := txn.Get([]byte(userPrefix + id))
+		if err != nil {
+			return err
+		}
+		return item.Value(func(val []byte) error {
+			return json.Unmarshal(val, &user)
+		})
+	})
+	if err != nil {
+		return nil, err
+	}
+	return &user, nil
+}
+
+func findUserIDByEmail(email string) (string, error) {
+	var id string
+	err := GetDB().View(func(txn *badger.Txn) error {
+		item, err := txn.Get([]byte(emailIndexPref + email))
+		if err != nil {
+			return err
+		}
+		return item.Value(func(v []byte) error {
+			id = string(v)
+			return nil
+		})
+	})
+	return id, err
+}
+
+func FindUserByEmail(email string) (*User, error) {
+	id, err := findUserIDByEmail(email)
+	if err != nil {
+		return nil, err
+	}
+	return FindUserByID(id)
+}
+
+func ListUsers() ([]*User, error) {
+	users := []*User{}
+	err := GetDB().View(func(txn *badger.Txn) error {
+		it := txn.NewIterator(badger.DefaultIteratorOptions)
+		defer it.Close()
+		for it.Seek([]byte(userPrefix)); it.ValidForPrefix([]byte(userPrefix)); it.Next() {
+			item := it.Item()
+			err := item.Value(func(v []byte) error {
+				var u User
+				if err := json.Unmarshal(v, &u); err == nil {
+					users = append(users, &u)
+				}
+				return nil
+			})
+			if err != nil {
+				return err
+			}
+		}
+		return nil
+	})
+	return users, err
+}