feat(isGraphQlValidator): add validation for graphQl queries

.gitignore

@@ -10,4 +10,5 @@ yarn.lock
 /index.js
 validator.js
 validator.min.js
+.idea
 

README.md

@@ -113,6 +113,7 @@ Validator                               | Description
 **isFQDN(str [, options])**             | check if the string is a fully qualified domain name (e.g. domain.com).<br/><br/>`options` is an object which defaults to `{ require_tld: true, allow_underscores: false, allow_trailing_dot: false, allow_numeric_tld: false, allow_wildcard: false, ignore_max_length: false }`.<br/><br/>`require_tld` - If set to false the validator will not check if the domain includes a TLD.<br/>`allow_underscores` - if set to true, the validator will allow underscores in the domain.<br/>`allow_trailing_dot` - if set to true, the validator will allow the domain to end with a `.` character.<br/>`allow_numeric_tld` - if set to true, the validator will allow the TLD of the domain to be made up solely of numbers.<br />`allow_wildcard` - if set to true, the validator will allow domains starting with `*.` (e.g. `*.example.com` or `*.shop.example.com`).<br/>`ignore_max_length` - if set to true, the validator will not check for the standard max length of a domain.<br/>
 **isFreightContainerID(str)**                      | alias for `isISO6346`, check if the string is a valid [ISO 6346](https://en.wikipedia.org/wiki/ISO_6346) shipping container identification.
 **isFullWidth(str)**                    | check if the string contains any full-width chars.
+**isValidGraphQLQuery(str [, options])** | check if the string is valid graphql query (note: uses parse function from graphql package).<br/><br/>`options` is an object which defaults to `{ allow_primitives: false }`. If `allow_primitives` is true, the primitives 'true', 'false' and 'null' are accepted as valid graphql query values.
 **isHalfWidth(str)**                    | check if the string contains any half-width chars.
 **isHash(str, algorithm)**              | check if the string is a hash of type algorithm.<br/><br/>Algorithm is one of `['crc32', 'crc32b', 'md4', 'md5', 'ripemd128', 'ripemd160', 'sha1', 'sha256', 'sha384', 'sha512', 'tiger128', 'tiger160', 'tiger192']`.
 **isHexadecimal(str)**                  | check if the string is a hexadecimal number.

src/index.js

@@ -129,6 +129,7 @@
 import isStrongPassword from './lib/isStrongPassword';
 
 import isVAT from './lib/isVAT';
+import isValidGraphQLQuery from "./lib/isValidGraphQLQuery";
 
 const version = '13.15.0';
 
@@ -245,6 +246,7 @@
   isLicensePlate,
   isVAT,
   ibanLocales,
+  isValidGraphQLQuery,
 };
 
 export default validator;

src/lib/isValidGraphQLQuery.js

@@ -0,0 +1,23 @@
+import assertString from './util/assertString';
+import { parse } from 'graphql';
+import merge from './util/merge';
+
+const default_json_options = {
+  allow_primitives: false,
+};
+
+export default function isValidGraphQLQuery(input, options) {
+  assertString(input);
+  try {
+    options = merge(options, default_json_options);
+    let primitives = [];
+    if (options.allow_primitives) {
+      primitives = [null, false, true];
+    }
+
+    const obj = parse(input);
+    return includes(primitives, obj) || (!!obj && typeof obj === 'object');
+  } catch (e) {
+    return false;
+  };
+}