Test for custom checks

 🐿 v2.6.0

README.md

@@ -9,7 +9,7 @@ FT.com is built up of dozens of microservices, that are deployed dozens of times
 
 Smoke tests are designed to be a quick sanity check against a set of endpoints to check that they are actually working, rendering the elements that you expect and haven't introduced any performance regressions.
 
-Rather than the chore of writing tests, simply add some JS config (default location - tests/smoke.js) with some URLs (and optional headers) and some expectations. 
+Rather than the chore of writing tests, simply add some JS config (default location - tests/smoke.js) with some URLs (and optional headers) and some expectations.
 
 `n-test smoke`
 
@@ -83,8 +83,21 @@ module.exports = [
 **Using programatically**
 
 ```
-const nTest = require('@financial-times/n-test');
-nTest.smoke.run({ auth: true, host: 'local.ft.com:3002' })
+const SmokeTests = require('@financial-times/n-test').SmokeTests;
+const smoke = new SmokeTests({ headers: { globalHeader: true },  host: 'local.ft.com:3002' });
+
+//Add custom checks like so:
+smoke.addCheck('custom', async (testPage) => {
+    const metrics = await testPage.page.metrics();
+
+    return {
+        expected: `no more than ${testPage.check.custom} DOM nodes`,
+        actual: `${metrics.Nodes} nodes`,
+        result: testPage.check.custom >= metrics.Nodes
+    }
+});
+
+nTest.smoke.runf
 	.then((results) => { //all passed })
 	.catch((results) => { //some failed });
 

lib/smoke/index.js

@@ -3,8 +3,6 @@ const fs = require('fs');
 const puppeteer = require('puppeteer');
 const directly = require('directly');
 
-
-const test = require('./test');
 const checks = require('./checks');
 const filterConfigs = require('./filter-configs');
 const verifyUrl = require('./verify-url');

lib/smoke/test-page.js

@@ -18,28 +18,27 @@ class TestPage {
 			this.url = this.url.replace('http:', 'https:');
 		}
 
-		this.requestHeaders = options.headers;
+		this.requestHeaders = options.headers || null;
 		this.method = options.method || 'GET';
-		this.postData = options.body;
+		this.postData = options.body || null;
 		this.dimensions = DIMENSIONS[options.breakpoint] || DIMENSIONS['XL'];
 
-		this.check = {
-			status: options.status,
-			cssCoverage: options.cssCoverage,
-			pageErrors: options.pageErrors,
-			cacheHeaders: options.cacheHeaders,
-			content: options.content,
-			performance: options.performance,
-			elements: options.elements
-		};
-
 
 		this.pageErrors = [];
 		this.consoleMessages = [];
 		this.coverageReports = [];
 		this.redirects = [];
 		this.response = null;
 		this.headers = null;
+
+		this.check = {};
+
+		Object.entries(options).forEach(([name, val]) => {
+			//Assume anything in options we haven't already claimed is an assertion to check
+			if(typeof this[name] === 'undefined') {
+				this.check[name] = val;
+			}
+		});
 	}
 
 	async init (browser) {

lib/smoke/verify-url.js

@@ -11,10 +11,12 @@ const verifyUrl = (testPage, browser, tests) => async () => {
 		tests: {}
 	};
 
-	const checks = Object.entries(testPage.check).map(([name, value]) => {
-		return (typeof value === 'undefined' ? Promise.resolve() : Promise.resolve(tests[name](testPage)).then(result => ({ name, results: [].concat(result) })));
+	const checks = Object.entries(tests).map(([name, testFn]) => {
+		const expectation = testPage.check[name];
+		return (typeof expectation === 'undefined' ? Promise.resolve() : Promise.resolve(testFn(testPage)).then(result => ({ name, results: [].concat(result) })));
 	});
 
+
 	const checkResults = await Promise.all(checks);
 	console.log(`Testing URL: ${testPage.url}`);
 	checkResults

test/fixtures/smoke-custom-check.js

@@ -0,0 +1,8 @@
+module.exports = [{
+		urls: {
+			'/status/200': {
+				custom: 20
+			}
+		}
+	}
+];

test/tasks/smoke.js

@@ -70,4 +70,29 @@ describe('Smoke Tests of the Smoke', () => {
 		});
 	});
 
+	describe('Adding custom checks', () => {
+		test('should allow adding custom assertions',(done) => {
+
+			const smoke = new SmokeTests({
+				host: 'http://localhost:3004',
+				config: 'test/fixtures/smoke-custom-check.js'
+			});
+
+			smoke.addCheck('custom', async (testPage) => {
+				const metrics = await testPage.page.metrics();
+
+				return {
+					expected: `no more than ${testPage.check.custom} DOM nodes`,
+					actual: `${metrics.Nodes} nodes`,
+					result: testPage.check.custom >= metrics.Nodes
+				}
+			});
+			return smoke.run()
+			.then((results) => {
+				expect(results.passed.length).toEqual(1);
+				expect(results.failed.length).toEqual(0);
+				done();
+			});
+		});
+	});
 });