memory db

Author: Snowflake107

README.md

@@ -13,8 +13,13 @@ $ npm i --save @devsnowflake/jsql
 
 ```js
 const { Database } = require("@devsnowflake/jsql");
+
+// file based
 const db = new Database("./database.json");
 
+// in-memory
+const db = new Database(":memory:");
+
 // creating a table
 db.prepare(`CREATE TABLE IF NOT EXISTS "DEMO" ("key" TEXT, "value" TEXT)`).run();
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@devsnowflake/jsql",
-  "version": "1.0.0",
+  "version": "1.0.1",
   "description": "Use JSON as SQL.",
   "main": "index.js",
   "types": "typings/index.d.ts",

src/jsql/Database.js

@@ -8,14 +8,19 @@ const handlers = {
 };
 
 class Database {
-    constructor(name) {
-        this.name = name;
-        if (!fs.existsSync(this.name)) fs.writeFileSync(this.name, '{}');
+    constructor(name, memory = false) {
+        this.name = memory === true ? ':memory:' : name;
+        this.memory = !memory && this.name === ':memory:' ? true : Boolean(memory);
+        this._memdb = {};
+
+        Object.defineProperty(this, '_memdb', { enumerable: false });
+
+        if (!this.memory && !fs.existsSync(this.name)) fs.writeFileSync(this.name, '{}');
     }
 
     get db() {
         try {
-            const db = JSON.parse(fs.readFileSync(this.name, 'utf-8'));
+            const db = this.memory ? this._memdb : JSON.parse(fs.readFileSync(this.name, 'utf-8'));
             return db;
         } catch {
             throw new Error('malformed database');
@@ -27,7 +32,8 @@ class Database {
     }
 
     write(data) {
-        fs.writeFileSync(this.name, JSON.stringify(data));
+        if (!this.memory) fs.writeFileSync(this.name, JSON.stringify(data));
+        else this._memdb = data;
     }
 
     run(query) {
@@ -67,4 +73,4 @@ class Database {
     }
 }
 
-module.exports = Database;
+module.exports = Database;

src/sql/parser.js

@@ -4,9 +4,9 @@ const parser = new Parser();
 module.exports.parse = function (query) {
     try {
         return parser.astify(query);
-    } catch(e) {
-        const expected = [...new Set((e.expected ?? []).filter(m => m.type === "literal").map((m) => m.text))];
-        throw new SyntaxError(`Expected ${expected.join(", ")} but received "${e.found}"!`);
+    } catch (e) {
+        const expected = [...new Set((e.expected ?? []).filter((m) => m.type === 'literal').map((m) => m.text))];
+        throw new SyntaxError(`Expected ${expected.join(', ')} but received "${e.found}"!`);
     }
 };
 

typings/index.d.ts

@@ -1,7 +1,6 @@
-import { AST } from "node-sql-parser"
-
-declare module "jsql" {
+import { AST } from 'node-sql-parser';
 
+declare module 'jsql' {
     export interface Handlers {
         create: (q: AST) => void;
         select: (q: AST) => any[];
@@ -24,13 +23,13 @@ declare module "jsql" {
     }
 
     export class Database {
-        constructor(name: string);
+        memory: boolean;
+        constructor(name: string, memory?: boolean);
         get db(): any;
         static get handlers(): Handlers;
         write(data: any): void;
         run(query: Statement): any;
         prepare(query: Statement): DatabasePrepare;
         parse(statement: Statement): string;
     }
-
-}
+}