Support externalising attachments in HTML formatter (#2413)

Author: davidjgoss

.gitignore

@@ -8,10 +8,7 @@ coverage/
 lib/
 node_modules
 tmp/
-reports/*.html
-reports/*.ndjson
-reports/*.txt
-reports/*.xml
+reports/
 yarn-error.log
 .vscode
 .DS_Store

CHANGELOG.md

@@ -8,6 +8,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 Please see [CONTRIBUTING.md](./CONTRIBUTING.md) on how to contribute to Cucumber.
 
 ## [Unreleased]
+### Added
+- Support externalising attachments in HTML formatter (see [documentation](./docs/formatters.md#html)) ([#2413](https://github.com/cucumber/cucumber-js/pull/2413))
+- Support linking to external content via attachments (see [documentation](./docs/support_files/attachments.md#links)) ([#2413](https://github.com/cucumber/cucumber-js/pull/2413))
 
 ## [10.8.0] - 2024-05-26
 ### Added

docs/formatters.md

@@ -90,6 +90,22 @@ You can:
 - Filter to specific statuses
 - Search by keywords or tag expressions
 
+#### Attachments
+
+By default, the HTML report includes all attachments from your test run as embedded data. This is simple and convenient, with the file being completely standalone and portable. But it can make for a _very_ large file if you have a lot of large attachments like screenshots, videos and other media. You can optionally have attachments saved to external files instead, if that works better for you:
+
+```json
+{
+  "formatOptions": {
+    "html": {
+      "externalAttachments": true
+    }
+  }
+}
+```
+
+This will cause attachments to be saved in the same directory as the report file, with filenames that look like `attachment-8e7c5d3d-1ef0-4be6-86e0-16362bad9531.png`. If you want to put the report file somewhere - say, a web server - to be viewed, you'll need to bring those files along with it.
+
 ### `message`
 
 Outputs all the [Cucumber Messages](https://github.com/cucumber/messages) for the test run as newline-delimited JSON, which can then be consumed by other tools.

docs/support_files/attachments.md

@@ -127,3 +127,25 @@ After(function () {
 ```
 
 Anything you log will be attached as a string with a MIME type of `text/x.cucumber.log+plain`
+
+## Links
+
+You can attach one or more links from your support code with the `link` function:
+
+```javascript
+var {Before, After} = require('@cucumber/cucumber');
+
+Before(function () {
+  this.link('https://cucumber.io');
+});
+
+After(function () {
+  this.link(
+    'https://github.com/cucumber/cucumber-js',
+    'https://github.com/cucumber/cucumber-jvm',
+    'https://github.com/cucumber/cucumber-ruby'
+  );
+});
+```
+
+Links will be attached as a string with a MIME type of `text/uri-list`

docs/support_files/world.md

@@ -60,6 +60,7 @@ By default, the world is an instance of Cucumber's built-in `World` class. Cucum
 
 * `this.attach`: a method for adding [attachments](./attachments.md) to hooks/steps
 * `this.log`: a method for [logging](./attachments.md#logging) information from hooks/steps
+* `this.link`: a method for [linking](./attachments.md#links) to URLs from hooks/steps
 * `this.parameters`: an object of parameters passed in via configuration (see below)
 
 Your custom world will also receive these arguments, but it's up to you to decide what to do with them and they can be safely ignored.

exports/root/report.api.md

@@ -339,6 +339,8 @@ export interface IWorld<ParametersType = any> {
     // (undocumented)
     readonly attach: ICreateAttachment;
     // (undocumented)
+    readonly link: ICreateLink;
+    // (undocumented)
     readonly log: ICreateLog;
     // (undocumented)
     readonly parameters: ParametersType;
@@ -349,6 +351,8 @@ export interface IWorldOptions<ParametersType = any> {
     // (undocumented)
     attach: ICreateAttachment;
     // (undocumented)
+    link: ICreateLink;
+    // (undocumented)
     log: ICreateLog;
     // (undocumented)
     parameters: ParametersType;
@@ -532,10 +536,12 @@ export const When: IDefineStep_2;
 
 // @public (undocumented)
 export class World<ParametersType = any> implements IWorld<ParametersType> {
-    constructor({ attach, log, parameters }: IWorldOptions<ParametersType>);
+    constructor({ attach, log, link, parameters, }: IWorldOptions<ParametersType>);
     // (undocumented)
     readonly attach: ICreateAttachment;
     // (undocumented)
+    readonly link: ICreateLink;
+    // (undocumented)
     readonly log: ICreateLog;
     // (undocumented)
     readonly parameters: ParametersType;

features/html_formatter.feature

@@ -0,0 +1,36 @@
+Feature: HTML formatter
+
+  Rule: Attachments except logs are externalised based on the externalAttachments option
+
+    Background:
+      Given a file named "features/a.feature" with:
+        """
+        Feature: a feature
+          Scenario: a scenario
+            Given a step
+        """
+      And a file named "features/steps.js" with:
+        """
+        const {Given, world} = require('@cucumber/cucumber')
+
+        Given('a step', () => {
+          world.log('Logging some info')
+          world.link('https://cucumber.io')
+          world.attach(btoa('Base64 text'), 'base64:text/plain')
+          world.attach('Plain text', 'text/plain')
+        })
+        """
+
+    Scenario: Without externalAttachments option
+      When I run cucumber-js with `--format html:html.out`
+      Then it passes
+      And the html formatter output is complete
+      And the formatter has no externalised attachments
+
+    Scenario: With externalAttachments option
+      When I run cucumber-js with `--format html:html.out --format-options '{"html":{"externalAttachments":true}}'`
+      Then it passes
+      And the html formatter output is complete
+      And the formatter has these external attachments:
+        | Base64 text |
+        | Plain text  |

features/step_definitions/formatter_steps.ts

@@ -2,7 +2,7 @@ import path from 'node:path'
 import { expect, use } from 'chai'
 import chaiExclude from 'chai-exclude'
 import fs from 'mz/fs'
-import { Then } from '../../'
+import { Then, DataTable } from '../../'
 import {
   ignorableKeys,
   normalizeJsonOutput,
@@ -69,3 +69,27 @@ Then('the html formatter output is complete', async function (this: World) {
   expect(actual).to.contain('<html lang="en">')
   expect(actual).to.contain('</html>')
 })
+
+Then(
+  'the formatter has no externalised attachments',
+  async function (this: World) {
+    const actual = fs
+      .readdirSync(this.tmpDir)
+      .filter((filename) => filename.startsWith('attachment-')).length
+    expect(actual).to.eq(0)
+  }
+)
+
+Then(
+  'the formatter has these external attachments:',
+  async function (this: World, table: DataTable) {
+    const actual = fs
+      .readdirSync(this.tmpDir)
+      .filter((filename) => filename.startsWith('attachment-'))
+      .map((filename) =>
+        fs.readFileSync(path.join(this.tmpDir, filename), { encoding: 'utf-8' })
+      )
+    actual.sort()
+    expect(actual).to.deep.eq(table.raw().map((row) => row[0]))
+  }
+)

package-lock.json

@@ -218,7 +218,7 @@
     "@cucumber/gherkin": "28.0.0",
     "@cucumber/gherkin-streams": "5.0.1",
     "@cucumber/gherkin-utils": "9.0.0",
-    "@cucumber/html-formatter": "21.3.1",
+    "@cucumber/html-formatter": "21.6.0",
     "@cucumber/message-streams": "4.0.1",
     "@cucumber/messages": "24.1.0",
     "@cucumber/tag-expressions": "6.1.0",
@@ -239,6 +239,7 @@
     "lodash.merge": "^4.6.2",
     "lodash.mergewith": "^4.6.2",
     "luxon": "3.2.1",
+    "mime": "^3.0.0",
     "mkdirp": "^2.1.5",
     "mz": "^2.7.0",
     "progress": "^2.0.3",