Added ability to add user

cmd/data/db.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 
 	"github.com/go-sql-driver/mysql"
+	"golang.org/x/crypto/bcrypt"
 )
 
 type DB struct {
@@ -32,3 +33,28 @@ func OpenDB(dbName string) (*DB, error) {
 
 	return &db, nil
 }
+
+func (db *DB) AddUser(user, pass, first, last string, writer, editor, admin bool) error {
+	hashedPass, err := bcrypt.GenerateFromPassword([]byte(pass), bcrypt.DefaultCost)
+	if err != nil {
+		return fmt.Errorf("error creating password hash: %v", err)
+	}
+
+	if !permissionsOK(writer, editor, admin) {
+		return fmt.Errorf("error with mutually exclusive user permissions: writer = %v, editor = %v, admin = %v",
+			writer, editor, admin)
+	}
+
+	query := `
+    INSERT INTO users
+        (username, password, first_name, last_name, writer, editor, admin)
+    VALUES
+        (?, ?, ?, ?, ?, ?)
+    `
+	_, err = db.Exec(query, user, hashedPass, first, last, writer, editor, admin)
+	if err != nil {
+		return fmt.Errorf("error inserting user into DB: %v", err)
+	}
+
+	return nil
+}

cmd/data/helpers.go

@@ -50,3 +50,9 @@ func getCredentials() (string, string, error) {
 
 	return user, pass, nil
 }
+
+func permissionsOK(writer, editor, admin bool) bool {
+	return writer && !editor && !admin ||
+		!writer && editor && !admin ||
+		!writer && !editor && admin
+}