[GitlabCoverage] Add badge for code coverage (#5262)

* Add base for GitLab code coverage badge

* Change examples to repos which have implemented code coverage reporting
in GitLab UI

* Add tests for Gitlab Coverage badge

* Fix test data that was not changed

* Update code according to new branch detection

Signed-off-by: Hrishikesh Patil <hrishikeshpatil.754@gmail.com>

* Update docs and examples, make branch required option that was missed in
previous commit

Signed-off-by: Hrishikesh Patil <hrishikeshpatil.754@gmail.com>

* Apply suggestions from PR discussion

Signed-off-by: Hrishikesh Patil <hrishikeshpatil.754@gmail.com>

* Remove default value of branch param

Signed-off-by: Hrishikesh Patil <hrishikeshpatil.754@gmail.com>

* Apply further discussed changes to service

Signed-off-by: Hrishikesh Patil <hrishikeshpatil.754@gmail.com>

* Fix tests that were failing

Signed-off-by: Hrishikesh Patil <hrishikeshpatil.754@gmail.com>

* Add fetch and transform functions

Signed-off-by: Hrishikesh Patil <hrishikeshpatil.754@gmail.com>

* Add examples and tests for custom job name

Signed-off-by: Hrishikesh Patil <hrishikeshpatil.754@gmail.com>

* Add finishing touches

Signed-off-by: Hrishikesh Patil <hrishikeshpatil.754@gmail.com>

* Change to a working example

Signed-off-by: Hrishikesh Patil <hrishikeshpatil.754@gmail.com>

Co-authored-by: repo-ranger[bot] <39074581+repo-ranger[bot]@users.noreply.github.com>

services/gitlab/gitlab-coverage.service.js

@@ -0,0 +1,149 @@
+'use strict'
+
+const Joi = require('@hapi/joi')
+const { coveragePercentage } = require('../color-formatters')
+const { optionalUrl } = require('../validators')
+const { BaseSvgScrapingService, NotFound } = require('..')
+
+const schema = Joi.object({
+  message: Joi.string()
+    .regex(/^([0-9]+\.[0-9]+%)|unknown$/)
+    .required(),
+}).required()
+
+const queryParamSchema = Joi.object({
+  gitlab_url: optionalUrl,
+  job_name: Joi.string(),
+}).required()
+
+const documentation = `
+<p>
+  Important: If your project is publicly visible, but the badge is like this:
+  <img src="https://img.shields.io/badge/coverage-not&nbsp;set&nbsp;up-red" alt="coverage not set up"/>
+</p>
+<p>
+  Check if your pipelines are publicly visible as well.<br />
+  Navigate to your project settings on GitLab and choose General Pipelines under CI/CD.<br />
+  Then tick the setting Public pipelines.
+</p>
+<p>
+  Now your settings should look like this:
+</p>
+<img src="https://user-images.githubusercontent.com/12065866/67156911-e225a180-f324-11e9-93ad-10aafbb3e69e.png" alt="Setting Public pipelines set"/>
+<p>
+Also make sure you have set up code covrage parsing as described <a href="https://docs.gitlab.com/ee/ci/pipelines/settings.html#test-coverage-parsing">here</a>
+</p>
+<p>
+  Your badge should be working fine now.
+</p>
+`
+
+module.exports = class GitlabCoverage extends BaseSvgScrapingService {
+  static get category() {
+    return 'coverage'
+  }
+
+  static get route() {
+    return {
+      base: 'gitlab/coverage',
+      pattern: ':user/:repo/:branch',
+      queryParamSchema,
+    }
+  }
+
+  static get examples() {
+    return [
+      {
+        title: 'Gitlab code coverage',
+        namedParams: {
+          user: 'gitlab-org',
+          repo: 'gitlab-runner',
+          branch: 'master',
+        },
+        staticPreview: this.render({ coverage: 67 }),
+        documentation,
+      },
+      {
+        title: 'Gitlab code coverage (specific job)',
+        namedParams: {
+          user: 'gitlab-org',
+          repo: 'gitlab-runner',
+          branch: 'master',
+        },
+        queryParams: { job_name: 'test coverage report' },
+        staticPreview: this.render({ coverage: 96 }),
+        documentation,
+      },
+      {
+        title: 'Gitlab code coverage (self-hosted)',
+        namedParams: { user: 'GNOME', repo: 'libhandy', branch: 'master' },
+        queryParams: { gitlab_url: 'https://gitlab.gnome.org' },
+        staticPreview: this.render({ coverage: 93 }),
+        documentation,
+      },
+      {
+        title: 'Gitlab code coverage (self-hosted, specific job)',
+        namedParams: { user: 'GNOME', repo: 'libhandy', branch: 'master' },
+        queryParams: {
+          gitlab_url: 'https://gitlab.gnome.org',
+          job_name: 'unit-test',
+        },
+        staticPreview: this.render({ coverage: 93 }),
+        documentation,
+      },
+    ]
+  }
+
+  static get defaultBadgeData() {
+    return { label: 'coverage' }
+  }
+
+  static render({ coverage }) {
+    return {
+      message: `${coverage.toFixed(0)}%`,
+      color: coveragePercentage(coverage),
+    }
+  }
+
+  async fetch({
+    user,
+    repo,
+    branch,
+    gitlab_url: baseUrl = 'https://gitlab.com',
+    job_name,
+  }) {
+    // Since the URL doesn't return a usable value when an invalid job name is specified,
+    // it is recommended to not use the query param at all if not required
+    job_name = job_name ? `?job=${job_name}` : ''
+    const url = `${baseUrl}/${user}/${repo}/badges/${branch}/coverage.svg${job_name}`
+    const errorMessages = {
+      401: 'repo not found',
+      404: 'repo not found',
+    }
+    return this._requestSvg({
+      schema,
+      url,
+      errorMessages,
+    })
+  }
+
+  static transform({ coverage }) {
+    if (coverage === 'unknown') {
+      throw new NotFound({ prettyMessage: 'not set up' })
+    }
+    return Number(coverage.slice(0, -1))
+  }
+
+  async handle({ user, repo, branch }, { gitlab_url, job_name }) {
+    const { message: coverage } = await this.fetch({
+      user,
+      repo,
+      branch,
+      gitlab_url,
+      job_name,
+    })
+    return this.constructor.render({
+      coverage: this.constructor.transform({ coverage }),
+    })
+  }
+}

services/gitlab/gitlab-coverage.tester.js

@@ -0,0 +1,64 @@
+'use strict'
+
+const { isIntegerPercentage } = require('../test-validators')
+const t = (module.exports = require('../tester').createServiceTester())
+
+t.create('Coverage (branch)')
+  .get('/gitlab-org/gitlab-runner/12-0-stable.json')
+  .expectBadge({
+    label: 'coverage',
+    message: isIntegerPercentage,
+  })
+
+t.create('Coverage (existent branch but coverage not set up)')
+  .get('/gitlab-org/gitlab-git-http-server/master.json')
+  .expectBadge({
+    label: 'coverage',
+    message: 'not set up',
+  })
+
+t.create('Coverage (nonexistent branch)')
+  .get('/gitlab-org/gitlab-runner/nope-not-a-branch.json')
+  .expectBadge({
+    label: 'coverage',
+    message: 'not set up',
+  })
+
+t.create('Coverage (nonexistent repo)')
+  .get('/this-repo/does-not-exist/neither-branch.json')
+  .expectBadge({
+    label: 'coverage',
+    message: 'inaccessible',
+  })
+
+t.create('Coverage (custom job)')
+  .get(
+    '/gitlab-org/gitlab-runner/12-0-stable.json?job_name=test coverage report'
+  )
+  .expectBadge({
+    label: 'coverage',
+    message: isIntegerPercentage,
+  })
+
+t.create('Coverage (custom invalid job)')
+  .get('/gitlab-org/gitlab-runner/12-0-stable.json?job_name=i dont exist')
+  .expectBadge({
+    label: 'coverage',
+    message: 'not set up',
+  })
+
+t.create('Coverage (custom gitlab URL)')
+  .get('/GNOME/libhandy/master.json?gitlab_url=https://gitlab.gnome.org')
+  .expectBadge({
+    label: 'coverage',
+    message: isIntegerPercentage,
+  })
+
+t.create('Coverage (custom gitlab URL and job)')
+  .get(
+    '/GNOME/libhandy/master.json?gitlab_url=https://gitlab.gnome.org&job_name=unit-test'
+  )
+  .expectBadge({
+    label: 'coverage',
+    message: isIntegerPercentage,
+  })