add listTables method - resolves #10

lib/DynamoDB.js

@@ -11,6 +11,7 @@
 var AWS = require('aws-sdk');
 var pick = require('object-pick');
 var Table = require('./Table');
+var ListTables = require('./methods/ListTables');
 
 module.exports = {
 	/**
@@ -49,6 +50,14 @@ module.exports = {
 		// Create a table and initialize
 		return this.table(schema.TableName).create(schema);
 	},
+	/**
+	 * Method that will instantiate a list tables object.
+	 *
+	 * @return {ListTables}				A ListTables object.
+	 */
+	listTables: function () {
+		return new ListTables(this);
+	},
 	/**
 	 * Initializes the database settings.
 	 *

lib/methods/ListTables.js

@@ -0,0 +1,60 @@
+'use strict';
+
+/**
+ * This class forms the builder pattern for listing all the tables.
+ *
+ * @author Sam Verschueren	  <sam.verschueren@gmail.com>
+ * @since  24 Jan. 2015
+ */
+
+// module dependencies
+var Promise = require('pinkie-promise');
+var pify = require('pify');
+
+/**
+ * Creates a new list tables object that can then be used to built the entire
+ * request.
+ *
+ * @param {DynamoDB}		dynamodb		The dynamodb object.
+ */
+function ListTables(dynamodb) {
+	this._dynamodb = dynamodb;
+}
+
+/**
+ * This method will execute the list table request that was built up.
+ *
+ * @return {Promise}						The promise object that resolves all the tables.
+ */
+ListTables.prototype.exec = function () {
+	var db = this._dynamodb._dynamodb;
+	var prefix = this._dynamodb._prefix;
+
+	if (!db) {
+		return Promise.reject(new Error('Call .connect() before executing queries.'));
+	}
+
+	function execHelper(result, params) {
+		result = result || [];
+		params = params || {};
+
+		return pify(db.service.listTables.bind(db.service), Promise)(params)
+			.then(function (data) {
+				result = result.concat(data.TableNames);
+
+				if (data.LastEvaluatedTableName) {
+					params.ExclusiveStartTableName = data.LastEvaluatedTableName;
+					return execHelper(result, params);
+				}
+
+				return prefix === undefined ? result : result.filter(function (table) {
+					return table.indexOf(prefix) === 0;
+				});
+			});
+	}
+
+	return execHelper();
+};
+
+// Export the module
+module.exports = ListTables;

readme.md

@@ -158,6 +158,20 @@ Employee.findOneAndRemove({Organisation: 'Amazon', Email: 'john.doe@amazon.com'}
     });
 ```
 
+### List all the tables
+
+You can retrieve a list of all the tables.
+
+```js
+db.listTables().exec().then(tables => {
+	console.log(tables);
+	//=> ['foo', 'bar', 'baz']
+});
+```
+
+If you passed in a `prefix` property in the connection object, only the tables with that prefix will
+be returned.
+
 ### Create a table
 
 A table can be created by either calling `create()` on a table instance or by calling `createTable` on the database instance.

test/methods/listTables.js

@@ -0,0 +1,36 @@
+import test from 'ava';
+import sinon from 'sinon';
+import db from '../../';
+
+db.connect();
+
+test.before(() => {
+	const stub = sinon.stub(db._dynamodb.service, 'listTables');
+	stub.onFirstCall().yields(undefined, {LastEvaluatedTableName: 'test.baz', TableNames: ['test.baz']});
+	stub.yields(undefined, {TableNames: ['test.foo', 'test.bar', 'prod.foo']});
+});
+
+test.after(() => {
+	db._dynamodb.service.listTables.restore();
+});
+
+test.serial('result', async t => {
+	t.same(await db.listTables().exec(), ['test.baz', 'test.foo', 'test.bar', 'prod.foo']);
+});
+
+test.serial('filter result on prefix', async t => {
+	db._prefix = 'test';
+
+	t.same(await db.listTables().exec(), ['test.foo', 'test.bar']);
+
+	db._prefix = undefined;
+});
+
+test.serial('error if not connected', async t => {
+	const original = db._dynamodb;
+	db._dynamodb = undefined;
+
+	await t.throws(db.listTables().exec(), 'Call .connect() before executing queries.');
+
+	db._dynamodb = original;
+});