feat: Exported validation function for request params validation

README.md

@@ -5,7 +5,7 @@ NPM module to generate swagger documentation for Express APIs with minimum addit
 >[![Downloads](https://badgen.net/npm/dt/swagger-generator-express)](https://www.npmjs.com/package/swagger-generator-express) [![npm dependents](https://badgen.net/npm/dependents/swagger-generator-express)](https://www.npmjs.com/package/swagger-generator-express?activeTab=dependents)
 
 ## Description
-This NPM module let's you generate swagger (OpenAPI) documentation for your Express APIs without putting in much extra efforts. You just need to follow the convention for your request and response objects, and the module will take care of the rest. This module will cover your controllers, API specs along with request and response object structures.
+This NPM module let's you validate and generate swagger (OpenAPI) documentation for your Express APIs without putting in much extra efforts. You just need to follow the convention for your request and response objects, and the module will take care of the rest. This module will cover your controllers, API specs along with request and response object structures.
 
 
 ## Usage ##
@@ -62,7 +62,7 @@ swagger.serveSwagger(app, "/swagger", options, {routePath : './src/routes/', req
 'use strict';
 var express = require('express');
 var router = express.Router();
-var validation = require('../middleware/validate');
+var { validation } = require('swagger-generator-express');
 var userController = require('../controller/user');
 var requestModel = require('../requestModel/users');
 
@@ -254,6 +254,29 @@ module.exports = {
 
 Open `http://`<app_host>`:`<app_port>`/swagger` in your browser to view the documentation.
 
+## Request Parameter Validation
+
+- Use `validation` function exported from this module to validate request params.
+
+```javascript
+'use strict';
+var express = require('express');
+var router = express.Router();
+var { validation } = require('swagger-generator-express');
+var userController = require('../controller/user');
+var requestModel = require('../requestModel/users');
+
+/**
+ * Function: validation
+ * Use validation function to validate request parameter.
+ * @param schema Joi schema for request.
+ */
+router.post('/', validation(requestModel[0]), userController.createUser);
+
+module.exports = router;
+```
+
+
 ## Pre-requisite
 
 - Node v10 or above

example/express-swagger-example/src/routes/users.js

@@ -1,7 +1,7 @@
 'use strict';
 var express = require('express');
 var router = express.Router();
-var validation = require('../middleware/validate');
+var { validation } = require('swagger-generator-express');
 var userController = require('../controller/user');
 var requestModel = require('../requestModel/users');
 

index.ts

@@ -6,6 +6,7 @@ import responsesEnum from './responsesEnum';
 import { isEmpty, map, get, has } from 'lodash';
 import fs from 'fs';
 import { resolve, join } from 'path';
+import expressValidation from './validation/validate';
 
 /**
  * This module will support all the functionality of swagger-spec-express with additonal
@@ -18,6 +19,7 @@ export = {
   swaggerize,
   createModel,
   serveSwagger,
+  validation: expressValidation
 };
 
 /**

package.json

@@ -1,7 +1,7 @@
 {
   "name": "swagger-generator-express",
   "title": "swagger-generator-express",
-  "version": "2.0.0",
+  "version": "2.1.0",
   "description": "Generate swagger documentation automatically using joi validation.",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",

validation/validate.ts

@@ -0,0 +1,111 @@
+'use strict';
+import Joi from '@hapi/joi'
+import ValidationError from './validation-error'
+import { assignIn, find, defaults } from 'lodash'
+
+const defaultOptions = {
+    contextRequest: false,
+    allowUnknownHeaders: true,
+    allowUnknownBody: true,
+    allowUnknownQuery: true,
+    allowUnknownParams: true,
+    allowUnknownCookies: true,
+    status: 400,
+    statusText: 'Bad Request'
+};
+let globalOptions = {};
+
+// maps the corresponding request object to an `express-validation` option
+const unknownMap: any = {
+    headers: 'allowUnknownHeaders',
+    body: 'allowUnknownBody',
+    query: 'allowUnknownQuery',
+    params: 'allowUnknownParams',
+    cookies: 'allowUnknownCookies'
+};
+
+export default function expressValidation(schema: any) {
+    if (!schema) throw new Error('Please provide a validation schema');
+
+    return async (req: any, res: any, next: any) => {
+        const errors: any = [];
+
+        // Set default options
+        const options = defaults({}, schema.options || {}, globalOptions, defaultOptions);
+
+        // NOTE: mutates `errors`
+        const requestInputType = ['headers', 'body', 'query', 'params', 'cookies'];
+
+        // tslint:disable-next-line:prefer-for-of
+        for (let index = 0; index < requestInputType.length; index++) {
+            const key = requestInputType[index];
+            const allowUnknown = options[unknownMap[key]];
+            const entireContext = options.contextRequest ? req : null;
+            if (schema[key]) {
+                await validate(errors, req[key], schema[key], key, allowUnknown, entireContext);
+            }
+        }
+      if (errors && errors.length === 0) return next();
+
+        // tslint:disable-next-line:new-parens
+        return next(new (ValidationError as any)(errors, options));
+    };
+};
+
+exports.ValidationError = ValidationError;
+
+exports.options = (opts: any) => {
+    if (!opts) {
+        globalOptions = {};
+        return;
+    }
+
+    globalOptions = defaults({}, globalOptions, opts);
+};
+
+/**
+ * validate checks the current `Request` for validations
+ * NOTE: mutates `request` in case the object is valid.
+ */
+async function validate(errObj: any, request: any, schema: any, location: any, allowUnknown: any, context: any) {
+    if (!request || !schema) return;
+
+    const joiOptions = {
+        context: context || request,
+        allowUnknown,
+        abortEarly: false
+    };
+
+    const {
+        error,
+        value
+    } = await Joi.object(schema).validate(request, joiOptions);
+
+    const errors = error;
+    if (!errors || errors.details.length === 0) {
+        assignIn(request, value); // joi responses are parsed into JSON
+        return;
+    }
+    // tslint:disable-next-line:no-shadowed-variable
+    errors.details.forEach((error) => {
+        const errorExists = find(errObj, (item)=> {
+            if (item && item.field === error.path && item.location === location) {
+                item.messages.push(error.message);
+                item.types.push(error.type);
+                return item;
+            }
+            return;
+        });
+
+        if (!errorExists) {
+            errObj.push({
+                field: error.path,
+                location,
+                messages: [error.message],
+                types: [error.type]
+            });
+        }
+
+    });
+    return errObj;
+};

validation/validation-error.ts

@@ -0,0 +1,27 @@
+'use strict';
+import { map, flatten } from 'lodash'
+
+function ValidationError (this: any, errors : any, options: any) {
+  this.name = 'ValidationError';
+  this.message = 'validation error';
+  this.errors = errors;
+  this.flatten = options.flatten;
+  this.status = options.status;
+  this.statusText = options.statusText;
+};
+ValidationError.prototype = Object.create(Error.prototype);
+
+ValidationError.prototype.toString = function () {
+  return JSON.stringify(this.toJSON());
+};
+
+ValidationError.prototype.toJSON = function () {
+  if (this.flatten) return flatten(map(this.errors, 'messages'));
+  return {
+    status: this.status,
+    statusText: this.statusText,
+    errors: this.errors
+  };
+};
+
+export default ValidationError;