Manejo de archivos

archivos/contenedor.js

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+
+const {promises:fs} = require('fs')
+
+class Contenedor {
+    constructor(filePath){
+        this.filePath = filePath
+        this.lastId = 0
+    }
+
+    async save(obj){
+        let data = await this.getAll()
+        const newObj = {id: ++this.lastId, ...obj};
+        console.log(`Nuevo objeto: `, newObj);
+        data = [...data, newObj];
+
+        await fs.writeFile(this.filePath, JSON.stringify(data, null, 2));
+        console.log(`Se creo archivo ${this.filePath}`);
+        return newObj
+    }
+
+    async getById(id){
+        let data = await this.getAll()
+        return data.find(data => data.id === id)
+    }
+
+    async getAll(){
+        try {
+            let raw = await fs.readFile(this.filePath, 'utf8');
+            let data = JSON.parse(raw);
+            let lastId = [0, ...data.map(item => item.id)]
+            this.lastId = Math.max(...lastId)
+            console.log(`Se leyo archivo ${this.filePath}, lastId: `, this.lastId);
+            return data;
+        } catch (e) {
+            if( e.code === 'ENOENT') {
+                try{
+                    await fs.writeFile(this.filePath, JSON.stringify([]));
+                    console.log(`Se creo archivo ${this.filePath}`);
+                    return []
+                } catch (error) {
+                    return `No se puede modificar los datos`
+                }
+            }
+        }
+    }
+
+    async deleteById(id){
+        let data = await this.getAll()
+        let datafiltered = data.filter(item => item.id != id)
+        console.log("delete by id", datafiltered)
+        try {
+            await fs.writeFile(this.filePath, JSON.stringify(datafiltered, null, 2))
+            return `Dato borrado`
+        } catch (error) {
+            return `No se puede modificar los datos`
+        }
+    }
+
+    async deleteAll(){
+        try {
+            await fs.writeFile(this.filePath, JSON.stringify([]));
+        } catch (error) {
+            return `No se puede modificar los datos`
+        }
+    }
+}
+
+module.exports = {Contenedor}
+// ( async () => {
+
+//     let data = new Contenedor("./data.json")
+//     let result
+
+//     result = await data.save({name: "Contenedor"})
+//     console.log(result)
+
+//     result = await data.deleteById(3)
+//     console.log(result)
+// })()
+
+// data.getAll()
+// .then((data) => {
+//     console.log(data)
+// })
+
+// data.getById(3)
+// .then((data) => {
+//     console.log(data)
+// })
+
+// data.deleteAll()
+// .then((data) => {
+//     console.log(data)
+// })

archivos/index.js

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+const { Contenedor } = require('./contenedor');
+
+
+( async () => {
+    const productos = new Contenedor("./products.json")
+
+    let result = ``
+
+    result = await productos.save({
+        title: "Producto 1",
+        price: 25.4,
+        thumbnail: "https://images.com/img1.jpg"
+    })
+    console.log(result)
+
+    result = await productos.save({
+        title: "Producto 2",
+        price: 52.21,
+        thumbnail: "https://images.com/img2.jpg"
+    })
+    console.log(result)
+
+    result = await productos.save({
+        title: "Producto 3",
+        price: 1552.26,
+        thumbnail: "https://images.com/img3.jpg"
+    })
+    console.log(result)
+
+    result = await productos.getById(2)
+    console.log("Producto 2: ",result)
+
+    result = await productos.getAll()
+    console.log(result)
+
+    result = await productos.deleteById(2)
+    console.log(result)
+
+    // result = await productos.deleteAll()
+})()
+