Adds Streams plugins

Also now only one plugin is available per action.

Author: JbIPS

lib/index.js

@@ -89,7 +89,7 @@
   */
 
 const {UnifileError} = require('./error.js');
-
+const {Transform} = require('stream');
 /**
  * Tells if a method needs authentification
  * @param {string} methodName - Name of the method to test
@@ -104,10 +104,14 @@ function isAuthentifiedFunction(methodName) {
 
 const HOOKS = {
 	ON_READ: 'onRead',
-	ON_WRITE: 'onWrite'
+	ON_READSTREAM: 'onReadStream',
+	ON_WRITE: 'onWrite',
+	ON_WRITESTREAM: 'onWriteStream'
 };
 
-const applyPlugins = (plugins, content) => plugins.reduce((data, action) => action(data), content);
+const applyPlugin = (plugin, content) => {
+	return plugin ? plugin(content) : content;
+};
 
 const connectors = Symbol('connectors');
 
@@ -126,10 +130,7 @@ class Unifile {
    */
 	constructor() {
 		this[connectors] = new Map();
-		this.plugins = Object.keys(HOOKS).reduce((memo, key) => {
-			memo[HOOKS[key]] = [];
-			return memo;
-		}, {});
+		this.plugins = {};
 	}
 
 	/**
@@ -149,8 +150,8 @@ class Unifile {
    * @param {Plugin} plugin - A plugin with at least one hook implemented
    */
 	ext(plugin) {
-		Object.keys(HOOKS).map((key) => HOOKS[key]).forEach((hook) => {
-			if(plugin.hasOwnProperty(hook)) this.plugins[hook].push(plugin[hook]);
+		Object.values(HOOKS).forEach((hook) => {
+			if(plugin.hasOwnProperty(hook)) this.plugins[hook] = plugin[hook];
 		});
 	}
 
@@ -272,7 +273,7 @@ class Unifile {
    * @return {external:Promise<null>} an empty promise.
    */
 	writeFile(session, connectorName, path, content) {
-		const input = applyPlugins(this.plugins[HOOKS.ON_WRITE], content);
+		const input = applyPlugin(this.plugins[HOOKS.ON_WRITE], content);
 		return this.callMethod(connectorName, session, 'writeFile', path, input);
 	}
 
@@ -284,7 +285,13 @@ class Unifile {
    * @return {external:WritableStream} a writable stream into the file
    */
 	createWriteStream(session, connectorName, path) {
-		return this.callMethod(connectorName, session, 'createWriteStream', path);
+		const content = this.callMethod(connectorName, session, 'createWriteStream', path);
+		const plugin = this.plugins[HOOKS.ON_WRITESTREAM];
+		if(plugin instanceof Transform) {
+			plugin.pipe(content);
+			return plugin;
+		}
+		return content;
 	}
 
 	/**
@@ -296,7 +303,7 @@ class Unifile {
    */
 	readFile(session, connectorName, path) {
 		return this.callMethod(connectorName, session, 'readFile', path)
-		.then((content) => applyPlugins(this.plugins[HOOKS.ON_READ], content));
+		.then((content) => applyPlugin(this.plugins[HOOKS.ON_READ], content));
 	}
 
 	/**
@@ -307,7 +314,12 @@ class Unifile {
    * @return {external:ReadableStream} a readable stream from the file
    */
 	createReadStream(session, connectorName, path) {
-		return this.callMethod(connectorName, session, 'createReadStream', path);
+		const content = this.callMethod(connectorName, session, 'createReadStream', path);
+		const plugin = this.plugins[HOOKS.ON_READSTREAM];
+		if(plugin instanceof Transform) {
+			return content.pipe(plugin);
+		}
+		return content;
 	}
 
 	/**

samples/extensions.js

@@ -6,8 +6,10 @@ const crypto = require('crypto');
 const Unifile = require('../lib/');
 const unifile = new Unifile();
 
-const cipher = crypto.createCipher('aes192', 'a password');
-const decipher = crypto.createDecipher('aes192', 'a password');
+const PWD = 'a password';
+
+const cipher = crypto.createCipher('aes192', PWD);
+const decipher = crypto.createDecipher('aes192', PWD);
 
 // Configure connectors
 const dbxconnector = new Unifile.DropboxConnector({

test/index.js

@@ -1,6 +1,6 @@
 'use strict';
 
-const PassThrough = require('stream').PassThrough;
+const {Readable, Writable, Transform, PassThrough} = require('stream');
 const chai = require('chai');
 chai.use(require('chai-as-promised'));
 const Promise = require('bluebird');
@@ -86,6 +86,7 @@ describe('Unifile class', function() {
 		let unifile;
 		let inMemoryFile = '';
 		beforeEach('Instanciation', function() {
+			inMemoryFile = '';
 			unifile = new Unifile();
 			unifile.use({
 				name: 'memory',
@@ -94,6 +95,23 @@ describe('Unifile class', function() {
 				writeFile: (session, path, content) => {
 					inMemoryFile = content;
 					return Promise.resolve();
+				},
+				createReadStream: (session, path) => {
+					return new Readable({
+						read(size) {
+							this.push('hello');
+							this.push(null);
+						}
+					});
+				},
+				createWriteStream: (session, path) => {
+					//return require('fs').createWriteStream('./test.log');
+					return new Writable({
+						write(chunk, encoding, callback) {
+							inMemoryFile += chunk.toString();
+							callback(null);
+						}
+					});
 				}
 			});
 		});
@@ -103,10 +121,8 @@ describe('Unifile class', function() {
 				onWrite: console.log,
 				onRead: console.log
 			});
-			expect(unifile.plugins.onRead).to.have.lengthOf(1);
-			expect(unifile.plugins.onWrite).to.have.lengthOf(1);
-			expect(unifile.plugins.onRead[0]).to.equal(console.log);
-			expect(unifile.plugins.onWrite[0]).to.equal(console.log);
+			expect(unifile.plugins.onRead).to.equal(console.log);
+			expect(unifile.plugins.onWrite).to.equal(console.log);
 		});
 
 		it('can modify the input on write action', function() {
@@ -126,18 +142,40 @@ describe('Unifile class', function() {
 			.should.eventually.equal('aa');
 		});
 
-		it('follow a chain of action in order', function() {
+		it('can modify the input on write stream', function(done) {
 			unifile.ext({
-				onRead: (input) => input.replace('b', 'a'),
-				onWrite: (input) => input.replace('a', 'b')
+				onWriteStream: new Transform({
+					transform(chunk, encoding, callback) {
+						callback(null, chunk.toString().toUpperCase());
+					}
+				})
+			});
+			const stream = unifile.createWriteStream({}, 'memory', '');
+			stream.on('end', () => {
+				expect(inMemoryFile).to.equal('HELLO');
+				done();
 			});
+			stream.end('hello');
+		});
+
+		it('can modify the input on read stream', function(done) {
+			inMemoryFile = 'hello';
 			unifile.ext({
-				onRead: (input) => input.replace('a', 'c'),
-				onWrite: (input) => input.replace('b', 'd')
+				onReadStream: new Transform({
+					transform(chunk, encoding, callback) {
+						callback(null, chunk.toString().toUpperCase());
+					}
+				})
+			});
+			const stream = unifile.createReadStream({}, 'memory', '');
+			const chunks = [];
+			stream.on('data', (chunk) => {
+				chunks.push(chunk);
+			});
+			stream.on('end', () => {
+				expect(Buffer.concat(chunks).toString()).to.equal('HELLO');
+				done();
 			});
-			return unifile.writeFile({}, 'memory', '', 'ab')
-			.then(() => expect(inMemoryFile).to.equal('db'))
-			.then(() => unifile.readFile({}, 'memory', '').should.eventually.equal('dc'));
 		});
 	});