add url validation public method (adamgibbons#273)

src/index.js

@@ -6,6 +6,7 @@ import {
   formatHeader,
   formatEvent,
   formatFooter,
+  urlRegex,
 } from './pipeline'
 
 function buildHeaderAndValidate(header) {
@@ -76,3 +77,7 @@ export function createEvents (events, headerAttributesOrCb, cb) {
 
   return resolvedCb(returnValue.error, returnValue.value)
 }
+
+export function isValidURL(url) {
+  return urlRegex.test(url);
+}

src/pipeline/index.js

@@ -1,6 +1,6 @@
 import { buildHeader, buildEvent } from './build'
 import { formatHeader, formatEvent, formatFooter } from './format'
-import { validateHeader, validateHeaderAndEvent } from './validate'
+import { validateHeader, validateHeaderAndEvent, urlRegex } from './validate'
 
 export {
   buildHeader,
@@ -9,5 +9,6 @@ export {
   formatEvent,
   formatFooter,
   validateHeader,
-  validateHeaderAndEvent
+  validateHeaderAndEvent,
+  urlRegex
 }

src/schema/index.js

@@ -4,7 +4,7 @@ import * as yup from 'yup'
 // taken from https://github.com/jquense/yup/issues/224#issuecomment-417172609
 // This does mean that the url validation error is
 // "url must match the following: ...." as opposed to "url must be a valid URL"
-const urlRegex = /^(?:([a-z0-9+.-]+):\/\/)(?:\S+(?::\S*)?@)?(?:(?:[1-9]\d?|1\d\d|2[01]\d|22[0-3])(?:\.(?:1?\d{1,2}|2[0-4]\d|25[0-5])){2}(?:\.(?:[1-9]\d?|1\d\d|2[0-4]\d|25[0-4]))|(?:(?:[a-z\u00a1-\uffff0-9]-*)*[a-z\u00a1-\uffff0-9]+)(?:\.(?:[a-z\u00a1-\uffff0-9]-*)*[a-z\u00a1-\uffff0-9]+)*\.?)(?::\d{2,5})?(?:[/?#]\S*)?$/
+export const urlRegex = /^(?:([a-z0-9+.-]+):\/\/)(?:\S+(?::\S*)?@)?(?:(?:[1-9]\d?|1\d\d|2[01]\d|22[0-3])(?:\.(?:1?\d{1,2}|2[0-4]\d|25[0-5])){2}(?:\.(?:[1-9]\d?|1\d\d|2[0-4]\d|25[0-4]))|(?:(?:[a-z\u00a1-\uffff0-9]-*)*[a-z\u00a1-\uffff0-9]+)(?:\.(?:[a-z\u00a1-\uffff0-9]-*)*[a-z\u00a1-\uffff0-9]+)*\.?)(?::\d{2,5})?(?:[/?#]\S*)?$/
 
 const dateTimeSchema = ({ required }) => yup.lazy((value) => {
   if (typeof value === 'number') {

test/index.spec.js

@@ -1,5 +1,5 @@
 import { expect } from 'chai'
-import { createEvent, createEvents } from '../src'
+import { createEvent, createEvents, isValidURL } from '../src'
 
 const invalidAttributes = { start: [] }
 const validAttributes = { start: [2000, 10, 5, 5, 0], duration: { hours: 1 } }
@@ -117,4 +117,40 @@ describe('ics', () => {
       })
     })
   })
+
+  describe(".isValidURL", () => {
+    [
+      {
+        result: true,
+        condition: "http urls",
+        url: "http://domain.com",
+      },
+      {
+        result: true,
+        condition: "https urls",
+        url: "https://domain.com",
+      },
+      {
+        result: true,
+        condition: "localhost urls",
+        url: "http://localhost:8080",
+      },
+      {
+        result: false,
+        condition: "urls that start with www",
+        url: "www.domain.com",
+      },
+      {
+        result: false,
+        condition: "urls that start with domain",
+        url: "domain.com",
+      },
+    ].forEach((test) => {
+      it(`${test.result ? "passes" : "fails"} for ${test.condition}`, () => {
+        const response = isValidURL(test.url);
+
+        expect(response).equal(test.result);
+      })
+    })
+  })
 })