wip

14 files changed, 122 insertions, 242 deletions

diff --git a/src/api/endpoints/drive/files.js b/src/api/endpoints/drive/files.ts
index cbfe720266..c1441c554b 100644
--- a/src/api/endpoints/drive/files.js
+++ b/src/api/endpoints/drive/files.ts
@@ -3,7 +3,7 @@
 /**
  * Module dependencies
  */
-import * as mongo from 'mongodb';
+import it from '../../it';
 import DriveFile from '../../models/drive-file';
 import serialize from '../../serializers/drive-file';
 
@@ -19,33 +19,25 @@ module.exports = (params, user, app) =>
 	new Promise(async (res, rej) =>
 {
 	// Get 'limit' parameter
-	let limit = params.limit;
-	if (limit !== undefined && limit !== null) {
-		limit = parseInt(limit, 10);
+	const [limit, limitErr] = it(params.limit).expect.number().range(1, 100).default(10).qed();
+	if (limitErr) return rej('invalid limit param');
 
-		// From 1 to 100
-		if (!(1 <= limit && limit <= 100)) {
-			return rej('invalid limit range');
-		}
-	} else {
-		limit = 10;
-	}
+	// Get 'since_id' parameter
+	const [sinceId, sinceIdErr] = it(params.since_id).expect.id().qed();
+	if (sinceIdErr) return rej('invalid since_id param');
 
-	const since = params.since_id || null;
-	const max = params.max_id || null;
+	// Get 'max_id' parameter
+	const [maxId, maxIdErr] = it(params.max_id).expect.id().qed();
+	if (maxIdErr) return rej('invalid max_id param');
 
 	// Check if both of since_id and max_id is specified
-	if (since !== null && max !== null) {
+	if (sinceId !== null && maxId !== null) {
 		return rej('cannot set since_id and max_id');
 	}
 
 	// Get 'folder_id' parameter
-	let folder = params.folder_id;
-	if (folder === undefined || folder === null) {
-		folder = null;
-	} else {
-		folder = new mongo.ObjectID(folder);
-	}
+	const [folderId, folderIdErr] = it(params.folder_id).expect.nullable.id().default(null).qed();
+	if (folderIdErr) return rej('invalid folder_id param');
 
 	// Construct query
 	const sort = {
@@ -53,16 +45,16 @@ module.exports = (params, user, app) =>
 	};
 	const query = {
 		user_id: user._id,
-		folder_id: folder
-	};
-	if (since !== null) {
+		folder_id: folderId
+	} as any;
+	if (sinceId) {
 		sort._id = 1;
 		query._id = {
-			$gt: new mongo.ObjectID(since)
+			$gt: sinceId
 		};
-	} else if (max !== null) {
+	} else if (maxId) {
 		query._id = {
-			$lt: new mongo.ObjectID(max)
+			$lt: maxId
 		};
 	}
 
diff --git a/src/api/endpoints/drive/files/create.js b/src/api/endpoints/drive/files/create.ts
index 9690b05cfd..7efd149813 100644
--- a/src/api/endpoints/drive/files/create.js
+++ b/src/api/endpoints/drive/files/create.ts
@@ -4,10 +4,8 @@
  * Module dependencies
  */
 import * as fs from 'fs';
-import * as mongo from 'mongodb';
-import File from '../../../models/drive-file';
+import it from '../../../it';
 import { validateFileName } from '../../../models/drive-file';
-import User from '../../../models/user';
 import serialize from '../../../serializers/drive-file';
 import create from '../../../common/add-file-to-drive';
 
@@ -45,15 +43,11 @@ module.exports = (file, params, user) =>
 	}
 
 	// Get 'folder_id' parameter
-	let folder = params.folder_id;
-	if (folder === undefined || folder === null) {
-		folder = null;
-	} else {
-		folder = new mongo.ObjectID(folder);
-	}
+	const [folderId, folderIdErr] = it(params.folder_id).expect.nullable.id().default(null).qed();
+	if (folderIdErr) return rej('invalid folder_id param');
 
 	// Create file
-	const driveFile = await create(user, buffer, name, null, folder);
+	const driveFile = await create(user, buffer, name, null, folderId);
 
 	// Serialize
 	const fileObj = await serialize(driveFile);
diff --git a/src/api/endpoints/drive/files/find.js b/src/api/endpoints/drive/files/find.ts
index 358767c5ed..393b8c5b98 100644
--- a/src/api/endpoints/drive/files/find.js
+++ b/src/api/endpoints/drive/files/find.ts
@@ -3,7 +3,7 @@
 /**
  * Module dependencies
  */
-import * as mongo from 'mongodb';
+import it from '../../../it';
 import DriveFile from '../../../models/drive-file';
 import serialize from '../../../serializers/drive-file';
 
@@ -18,25 +18,19 @@ module.exports = (params, user) =>
 	new Promise(async (res, rej) =>
 {
 	// Get 'name' parameter
-	const name = params.name;
-	if (name === undefined || name === null) {
-		return rej('name is required');
-	}
+	const [name, nameErr] = it(params.name).expect.string().required().qed();
+	if (nameErr) return rej('invalid name param');
 
 	// Get 'folder_id' parameter
-	let folder = params.folder_id;
-	if (folder === undefined || folder === null) {
-		folder = null;
-	} else {
-		folder = new mongo.ObjectID(folder);
-	}
+	const [folderId, folderIdErr] = it(params.folder_id).expect.nullable.id().default(null).qed();
+	if (folderIdErr) return rej('invalid folder_id param');
 
 	// Issue query
 	const files = await DriveFile
 		.find({
 			name: name,
 			user_id: user._id,
-			folder_id: folder
+			folder_id: folderId
 		}, {
 			fields: {
 				data: false
diff --git a/src/api/endpoints/drive/files/show.js b/src/api/endpoints/drive/files/show.ts
index 5ae98a4a7c..2024a56ca6 100644
--- a/src/api/endpoints/drive/files/show.js
+++ b/src/api/endpoints/drive/files/show.ts
@@ -3,7 +3,7 @@
 /**
  * Module dependencies
  */
-import * as mongo from 'mongodb';
+import it from '../../../it';
 import DriveFile from '../../../models/drive-file';
 import serialize from '../../../serializers/drive-file';
 
@@ -18,14 +18,13 @@ module.exports = (params, user) =>
 	new Promise(async (res, rej) =>
 {
 	// Get 'file_id' parameter
-	const fileId = params.file_id;
-	if (fileId === undefined || fileId === null) {
-		return rej('file_id is required');
-	}
+	const [fileId, fileIdErr] = it(params.file_id).expect.id().required().qed();
+	if (fileIdErr) return rej('invalid file_id param');
 
+	// Fetch file
 	const file = await DriveFile
 		.findOne({
-			_id: new mongo.ObjectID(fileId),
+			_id: fileId,
 			user_id: user._id
 		}, {
 			fields: {
diff --git a/src/api/endpoints/drive/files/update.js b/src/api/endpoints/drive/files/update.ts
index 8e2ff33e9d..595d501658 100644
--- a/src/api/endpoints/drive/files/update.js
+++ b/src/api/endpoints/drive/files/update.ts
@@ -3,7 +3,7 @@
 /**
  * Module dependencies
  */
-import * as mongo from 'mongodb';
+import it from '../../../it';
 import DriveFolder from '../../../models/drive-folder';
 import DriveFile from '../../../models/drive-file';
 import { validateFileName } from '../../../models/drive-file';
@@ -21,19 +21,13 @@ module.exports = (params, user) =>
 	new Promise(async (res, rej) =>
 {
 	// Get 'file_id' parameter
-	const fileId = params.file_id;
-	if (fileId === undefined || fileId === null) {
-		return rej('file_id is required');
-	}
-
-	// Validate id
-	if (!mongo.ObjectID.isValid(fileId)) {
-		return rej('incorrect file_id');
-	}
+	const [fileId, fileIdErr] = it(params.file_id).expect.id().required().qed();
+	if (fileIdErr) return rej('invalid file_id param');
 
+	// Fetch file
 	const file = await DriveFile
 		.findOne({
-			_id: new mongo.ObjectID(fileId),
+			_id: fileId,
 			user_id: user._id
 		}, {
 			fields: {
@@ -46,29 +40,19 @@ module.exports = (params, user) =>
 	}
 
 	// Get 'name' parameter
-	let name = params.name;
-	if (name) {
-		name = name.trim();
-		if (validateFileName(name)) {
-			file.name = name;
-		} else {
-			return rej('invalid file name');
-		}
-	}
+	const [name, nameErr] = it(params.name).expect.string().validate(validateFileName).qed();
+	if (nameErr) return rej('invalid name param');
+	if (name) file.name = name;
 
 	// Get 'folder_id' parameter
-	let folderId = params.folder_id;
+	const [folderId, folderIdErr] = it(params.folder_id).expect.nullable.id().qed();
+	if (folderIdErr) return rej('invalid folder_id param');
+
 	if (folderId !== undefined) {
 		if (folderId === null) {
 			file.folder_id = null;
 		} else {
-			// Validate id
-			if (!mongo.ObjectID.isValid(folderId)) {
-				return rej('incorrect folder_id');
-			}
-
-			folderId = new mongo.ObjectID(folderId);
-
+			// Fetch folder
 			const folder = await DriveFolder
 				.findOne({
 					_id: folderId,
diff --git a/src/api/endpoints/drive/files/upload_from_url.js b/src/api/endpoints/drive/files/upload_from_url.ts
index 3619a6f107..b6f4789317 100644
--- a/src/api/endpoints/drive/files/upload_from_url.js
+++ b/src/api/endpoints/drive/files/upload_from_url.ts
@@ -5,10 +5,8 @@
  */
 import * as URL from 'url';
 const download = require('download');
-import * as mongo from 'mongodb';
-import File from '../../../models/drive-file';
+import it from '../../../it';
 import { validateFileName } from '../../../models/drive-file';
-import User from '../../../models/user';
 import serialize from '../../../serializers/drive-file';
 import create from '../../../common/add-file-to-drive';
 
@@ -24,10 +22,8 @@ module.exports = (params, user) =>
 {
 	// Get 'url' parameter
 	// TODO: Validate this url
-	const url = params.url;
-	if (url == null) {
-		return rej('url is required');
-	}
+	const [url, urlErr] = it(params.url).expect.string().required().qed();
+	if (urlErr) return rej('invalid url param');
 
 	let name = URL.parse(url).pathname.split('/').pop();
 	if (!validateFileName(name)) {
@@ -35,18 +31,14 @@ module.exports = (params, user) =>
 	}
 
 	// Get 'folder_id' parameter
-	let folder = params.folder_id;
-	if (folder === undefined || folder === null) {
-		folder = null;
-	} else {
-		folder = new mongo.ObjectID(folder);
-	}
+	const [folderId, folderIdErr] = it(params.folder_id).expect.nullable.id().default(null).qed();
+	if (folderIdErr) return rej('invalid folder_id param');
 
 	// Download file
 	const data = await download(url);
 
 	// Create file
-	const driveFile = await create(user, data, name, null, folder);
+	const driveFile = await create(user, data, name, null, folderId);
 
 	// Serialize
 	const fileObj = await serialize(driveFile);
diff --git a/src/api/endpoints/drive/folders.js b/src/api/endpoints/drive/folders.ts
index 631d68769f..3f4a5bac0e 100644
--- a/src/api/endpoints/drive/folders.js
+++ b/src/api/endpoints/drive/folders.ts
@@ -3,7 +3,7 @@
 /**
  * Module dependencies
  */
-import * as mongo from 'mongodb';
+import it from '../../it';
 import DriveFolder from '../../models/drive-folder';
 import serialize from '../../serializers/drive-folder';
 
@@ -19,33 +19,25 @@ module.exports = (params, user, app) =>
 	new Promise(async (res, rej) =>
 {
 	// Get 'limit' parameter
-	let limit = params.limit;
-	if (limit !== undefined && limit !== null) {
-		limit = parseInt(limit, 10);
+	const [limit, limitErr] = it(params.limit).expect.number().range(1, 100).default(10).qed();
+	if (limitErr) return rej('invalid limit param');
 
-		// From 1 to 100
-		if (!(1 <= limit && limit <= 100)) {
-			return rej('invalid limit range');
-		}
-	} else {
-		limit = 10;
-	}
+	// Get 'since_id' parameter
+	const [sinceId, sinceIdErr] = it(params.since_id).expect.id().qed();
+	if (sinceIdErr) return rej('invalid since_id param');
 
-	const since = params.since_id || null;
-	const max = params.max_id || null;
+	// Get 'max_id' parameter
+	const [maxId, maxIdErr] = it(params.max_id).expect.id().qed();
+	if (maxIdErr) return rej('invalid max_id param');
 
 	// Check if both of since_id and max_id is specified
-	if (since !== null && max !== null) {
+	if (sinceId !== null && maxId !== null) {
 		return rej('cannot set since_id and max_id');
 	}
 
 	// Get 'folder_id' parameter
-	let folder = params.folder_id;
-	if (folder === undefined || folder === null) {
-		folder = null;
-	} else {
-		folder = new mongo.ObjectID(folder);
-	}
+	const [folderId, folderIdErr] = it(params.folder_id).expect.nullable.id().default(null).qed();
+	if (folderIdErr) return rej('invalid folder_id param');
 
 	// Construct query
 	const sort = {
@@ -53,16 +45,16 @@ module.exports = (params, user, app) =>
 	};
 	const query = {
 		user_id: user._id,
-		parent_id: folder
-	};
-	if (since !== null) {
+		parent_id: folderId
+	} as any;
+	if (sinceId) {
 		sort._id = 1;
 		query._id = {
-			$gt: new mongo.ObjectID(since)
+			$gt: sinceId
 		};
-	} else if (max !== null) {
+	} else if (maxId) {
 		query._id = {
-			$lt: new mongo.ObjectID(max)
+			$lt: maxId
 		};
 	}
 
diff --git a/src/api/endpoints/drive/folders/create.js b/src/api/endpoints/drive/folders/create.ts
index 9ba989c212..d327572af7 100644
--- a/src/api/endpoints/drive/folders/create.js
+++ b/src/api/endpoints/drive/folders/create.ts
@@ -3,7 +3,7 @@
 /**
  * Module dependencies
  */
-import * as mongo from 'mongodb';
+import it from '../../../it';
 import DriveFolder from '../../../models/drive-folder';
 import { isValidFolderName } from '../../../models/drive-folder';
 import serialize from '../../../serializers/drive-folder';
@@ -20,33 +20,17 @@ module.exports = (params, user) =>
 	new Promise(async (res, rej) =>
 {
 	// Get 'name' parameter
-	let name = params.name;
-	if (name !== undefined && name !== null) {
-		name = name.trim();
-		if (name.length === 0) {
-			name = null;
-		} else if (!isValidFolderName(name)) {
-			return rej('invalid name');
-		}
-	} else {
-		name = null;
-	}
+	const [name, nameErr] = it(params.name).expect.string().validate(isValidFolderName).default('無題のフォルダー').qed();
+	if (nameErr) return rej('invalid name param');
 
-	if (name == null) {
-		name = '無題のフォルダー';
-	}
-
-	// Get 'folder_id' parameter
-	let parentId = params.folder_id;
-	if (parentId === undefined || parentId === null) {
-		parentId = null;
-	} else {
-		parentId = new mongo.ObjectID(parentId);
-	}
+	// Get 'parent_id' parameter
+	const [parentId, parentIdErr] = it(params.parent_id).expect.nullable.id().default(null).qed();
+	if (parentIdErr) return rej('invalid parent_id param');
 
 	// If the parent folder is specified
 	let parent = null;
-	if (parentId !== null) {
+	if (parentId) {
+		// Fetch parent folder
 		parent = await DriveFolder
 			.findOne({
 				_id: parentId,
@@ -54,7 +38,7 @@ module.exports = (params, user) =>
 			});
 
 		if (parent === null) {
-			return reject('parent-not-found');
+			return rej('parent-not-found');
 		}
 	}
 
diff --git a/src/api/endpoints/drive/folders/find.js b/src/api/endpoints/drive/folders/find.ts
index 802d3a7909..041e9ccb2a 100644
--- a/src/api/endpoints/drive/folders/find.js
+++ b/src/api/endpoints/drive/folders/find.ts
@@ -3,7 +3,7 @@
 /**
  * Module dependencies
  */
-import * as mongo from 'mongodb';
+import it from '../../../it';
 import DriveFolder from '../../../models/drive-folder';
 import serialize from '../../../serializers/drive-folder';
 
@@ -18,18 +18,12 @@ module.exports = (params, user) =>
 	new Promise(async (res, rej) =>
 {
 	// Get 'name' parameter
-	const name = params.name;
-	if (name === undefined || name === null) {
-		return rej('name is required');
-	}
+	const [name, nameErr] = it(params.name).expect.string().required().qed();
+	if (nameErr) return rej('invalid name param');
 
 	// Get 'parent_id' parameter
-	let parentId = params.parent_id;
-	if (parentId === undefined || parentId === null) {
-		parentId = null;
-	} else {
-		parentId = new mongo.ObjectID(parentId);
-	}
+	const [parentId, parentIdErr] = it(params.parent_id).expect.id().qed();
+	if (parentIdErr) return rej('invalid parent_id param');
 
 	// Issue query
 	const folders = await DriveFolder
diff --git a/src/api/endpoints/drive/folders/show.js b/src/api/endpoints/drive/folders/show.ts
index 986d32cf60..3b3ed41719 100644
--- a/src/api/endpoints/drive/folders/show.js
+++ b/src/api/endpoints/drive/folders/show.ts
@@ -3,7 +3,7 @@
 /**
  * Module dependencies
  */
-import * as mongo from 'mongodb';
+import it from '../../../it';
 import DriveFolder from '../../../models/drive-folder';
 import serialize from '../../../serializers/drive-folder';
 
@@ -18,15 +18,13 @@ module.exports = (params, user) =>
 	new Promise(async (res, rej) =>
 {
 	// Get 'folder_id' parameter
-	const folderId = params.folder_id;
-	if (folderId === undefined || folderId === null) {
-		return rej('folder_id is required');
-	}
+	const [folderId, folderIdErr] = it(params.folder_id).expect.id().required().qed();
+	if (folderIdErr) return rej('invalid folder_id param');
 
 	// Get folder
 	const folder = await DriveFolder
 		.findOne({
-			_id: new mongo.ObjectID(folderId),
+			_id: folderId,
 			user_id: user._id
 		});
 
diff --git a/src/api/endpoints/drive/folders/update.js b/src/api/endpoints/drive/folders/update.ts
index 713e17b43e..81d414354c 100644
--- a/src/api/endpoints/drive/folders/update.js
+++ b/src/api/endpoints/drive/folders/update.ts
@@ -3,7 +3,7 @@
 /**
  * Module dependencies
  */
-import * as mongo from 'mongodb';
+import it from '../../../it';
 import DriveFolder from '../../../models/drive-folder';
 import { isValidFolderName } from '../../../models/drive-folder';
 import serialize from '../../../serializers/drive-file';
@@ -20,20 +20,13 @@ module.exports = (params, user) =>
 	new Promise(async (res, rej) =>
 {
 	// Get 'folder_id' parameter
-	const folderId = params.folder_id;
-	if (folderId === undefined || folderId === null) {
-		return rej('folder_id is required');
-	}
-
-	// Validate id
-	if (!mongo.ObjectID.isValid(folderId)) {
-		return rej('incorrect folder_id');
-	}
+	const [folderId, folderIdErr] = it(params.folder_id).expect.id().required().qed();
+	if (folderIdErr) return rej('invalid folder_id param');
 
 	// Fetch folder
 	const folder = await DriveFolder
 		.findOne({
-			_id: new mongo.ObjectID(folderId),
+			_id: folderId,
 			user_id: user._id
 		});
 
@@ -42,29 +35,17 @@ module.exports = (params, user) =>
 	}
 
 	// Get 'name' parameter
-	let name = params.name;
-	if (name) {
-		name = name.trim();
-		if (isValidFolderName(name)) {
-			folder.name = name;
-		} else {
-			return rej('invalid folder name');
-		}
-	}
+	const [name, nameErr] = it(params.name).expect.string().validate(isValidFolderName).qed();
+	if (nameErr) return rej('invalid name param');
+	if (name) folder.name = name;
 
 	// Get 'parent_id' parameter
-	let parentId = params.parent_id;
+	const [parentId, parentIdErr] = it(params.parent_id).expect.nullable.id().qed();
+	if (parentIdErr) return rej('invalid parent_id param');
 	if (parentId !== undefined) {
 		if (parentId === null) {
 			folder.parent_id = null;
 		} else {
-			// Validate id
-			if (!mongo.ObjectID.isValid(parentId)) {
-				return rej('incorrect parent_id');
-			}
-
-			parentId = new mongo.ObjectID(parentId);
-
 			// Get parent folder
 			const parent = await DriveFolder
 				.findOne({
diff --git a/src/api/endpoints/drive/stream.js b/src/api/endpoints/drive/stream.ts
index cd39261de8..6ede044f58 100644
--- a/src/api/endpoints/drive/stream.js
+++ b/src/api/endpoints/drive/stream.ts
@@ -3,7 +3,7 @@
 /**
  * Module dependencies
  */
-import * as mongo from 'mongodb';
+import it from '../../it';
 import DriveFile from '../../models/drive-file';
 import serialize from '../../serializers/drive-file';
 
@@ -18,35 +18,25 @@ module.exports = (params, user) =>
 	new Promise(async (res, rej) =>
 {
 	// Get 'limit' parameter
-	let limit = params.limit;
-	if (limit !== undefined && limit !== null) {
-		limit = parseInt(limit, 10);
+	const [limit, limitErr] = it(params.limit).expect.number().range(1, 100).default(10).qed();
+	if (limitErr) return rej('invalid limit param');
 
-		// From 1 to 100
-		if (!(1 <= limit && limit <= 100)) {
-			return rej('invalid limit range');
-		}
-	} else {
-		limit = 10;
-	}
+	// Get 'since_id' parameter
+	const [sinceId, sinceIdErr] = it(params.since_id).expect.id().qed();
+	if (sinceIdErr) return rej('invalid since_id param');
 
-	const since = params.since_id || null;
-	const max = params.max_id || null;
+	// Get 'max_id' parameter
+	const [maxId, maxIdErr] = it(params.max_id).expect.id().qed();
+	if (maxIdErr) return rej('invalid max_id param');
 
 	// Check if both of since_id and max_id is specified
-	if (since !== null && max !== null) {
+	if (sinceId !== null && maxId !== null) {
 		return rej('cannot set since_id and max_id');
 	}
 
 	// Get 'type' parameter
-	let type = params.type;
-	if (type === undefined || type === null) {
-		type = null;
-	} else if (!/^[a-zA-Z\/\-\*]+$/.test(type)) {
-		return rej('invalid type format');
-	} else {
-		type = new RegExp(`^${type.replace(/\*/g, '.+?')}$`);
-	}
+	const [type, typeErr] = it(params.type).expect.string().match(/^[a-zA-Z\/\-\*]+$/).qed();
+	if (typeErr) return rej('invalid type param');
 
 	// Construct query
 	const sort = {
@@ -54,19 +44,19 @@ module.exports = (params, user) =>
 	};
 	const query = {
 		user_id: user._id
-	};
-	if (since !== null) {
+	} as any;
+	if (sinceId) {
 		sort._id = 1;
 		query._id = {
-			$gt: new mongo.ObjectID(since)
+			$gt: sinceId
 		};
-	} else if (max !== null) {
+	} else if (maxId) {
 		query._id = {
-			$lt: new mongo.ObjectID(max)
+			$lt: maxId
 		};
 	}
 	if (type !== null) {
-		query.type = type;
+		query.type = new RegExp(`^${type.replace(/\*/g, '.+?')}$`);
 	}
 
 	// Issue query
diff --git a/src/api/endpoints/following/create.js b/src/api/endpoints/following/create.ts
index 46ff77ddf1..0edc122b94 100644
--- a/src/api/endpoints/following/create.js
+++ b/src/api/endpoints/following/create.ts
@@ -3,7 +3,7 @@
 /**
  * Module dependencies
  */
-import * as mongo from 'mongodb';
+import it from '../../it';
 import User from '../../models/user';
 import Following from '../../models/following';
 import notify from '../../common/notify';
@@ -23,15 +23,8 @@ module.exports = (params, user) =>
 	const follower = user;
 
 	// Get 'user_id' parameter
-	let userId = params.user_id;
-	if (userId === undefined || userId === null) {
-		return rej('user_id is required');
-	}
-
-	// Validate id
-	if (!mongo.ObjectID.isValid(userId)) {
-		return rej('incorrect user_id');
-	}
+	const [userId, userIdErr] = it(params.user_id, 'id', true);
+	if (userIdErr) return rej('invalid user_id param');
 
 	// 自分自身
 	if (user._id.equals(userId)) {
@@ -40,7 +33,7 @@ module.exports = (params, user) =>
 
 	// Get followee
 	const followee = await User.findOne({
-		_id: new mongo.ObjectID(userId)
+		_id: userId
 	}, {
 		fields: {
 			data: false,
diff --git a/src/api/endpoints/following/delete.js b/src/api/endpoints/following/delete.ts
index 1085013d03..7f0e908068 100644
--- a/src/api/endpoints/following/delete.js
+++ b/src/api/endpoints/following/delete.ts
@@ -3,7 +3,7 @@
 /**
  * Module dependencies
  */
-import * as mongo from 'mongodb';
+import it from '../../it';
 import User from '../../models/user';
 import Following from '../../models/following';
 import event from '../../event';
@@ -22,15 +22,8 @@ module.exports = (params, user) =>
 	const follower = user;
 
 	// Get 'user_id' parameter
-	let userId = params.user_id;
-	if (userId === undefined || userId === null) {
-		return rej('user_id is required');
-	}
-
-	// Validate id
-	if (!mongo.ObjectID.isValid(userId)) {
-		return rej('incorrect user_id');
-	}
+	const [userId, userIdErr] = it(params.user_id, 'id', true);
+	if (userIdErr) return rej('invalid user_id param');
 
 	// Check if the followee is yourself
 	if (user._id.equals(userId)) {
@@ -39,7 +32,7 @@ module.exports = (params, user) =>
 
 	// Get followee
 	const followee = await User.findOne({
-		_id: new mongo.ObjectID(userId)
+		_id: userId
 	}, {
 		fields: {
 			data: false,