[Tangled] Support for License Badges

services/tangled/tangled-helper.js

@@ -0,0 +1,61 @@
+const description = `
+[Tangled](https://tangled.org) does not expose license metadata via its AT Protocol record,
+so this badge fetches the project's LICENSE file from the default branch and matches it
+against well-known license texts to derive an SPDX id.
+`
+
+function httpErrorsFor(notFoundMessage = 'repo not found') {
+  return { 404: notFoundMessage }
+}
+
+// Order matters: more-specific patterns must precede subsets.
+const LICENSE_PATTERNS = [
+  { spdx: 'AGPL-3.0', re: /GNU AFFERO GENERAL PUBLIC LICENSE\s+Version 3/i },
+  { spdx: 'GPL-3.0', re: /GNU GENERAL PUBLIC LICENSE\s+Version 3/i },
+  { spdx: 'GPL-2.0', re: /GNU GENERAL PUBLIC LICENSE\s+Version 2/i },
+  { spdx: 'LGPL-3.0', re: /GNU LESSER GENERAL PUBLIC LICENSE\s+Version 3/i },
+  { spdx: 'LGPL-2.1', re: /GNU LESSER GENERAL PUBLIC LICENSE\s+Version 2\.1/i },
+  { spdx: 'Apache-2.0', re: /Apache License,?\s+Version 2\.0/i },
+  { spdx: 'MPL-2.0', re: /Mozilla Public License Version 2\.0/i },
+  { spdx: 'BSL-1.0', re: /Boost Software License - Version 1\.0/i },
+  { spdx: 'EPL-2.0', re: /Eclipse Public License - v 2\.0/i },
+  {
+    spdx: 'BSD-3-Clause',
+    re: /Redistribution and use in source and binary forms[\s\S]+Neither the name of[\s\S]+nor the names/i,
+  },
+  {
+    spdx: 'BSD-2-Clause',
+    re: /Redistribution and use in source and binary forms/i,
+  },
+  // ISC before 0BSD: ISC requires the copyright notice, 0BSD does not.
+  {
+    spdx: 'ISC',
+    re: /Permission to use, copy, modify, and\/or distribute this software[\s\S]+provided that the above copyright notice/i,
+  },
+  {
+    spdx: '0BSD',
+    re: /Permission to use, copy, modify, and\/or distribute this software/i,
+  },
+  {
+    spdx: 'MIT',
+    re: /Permission is hereby granted, free of charge, to any person obtaining a copy/i,
+  },
+  { spdx: 'WTFPL', re: /DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE/i },
+  {
+    spdx: 'Unlicense',
+    re: /This is free and unencumbered software released into the public domain/i,
+  },
+  { spdx: 'CC0-1.0', re: /Creative Commons (?:CC0|Zero) 1\.0/i },
+]
+
+const SCAN_BYTES = 4096
+
+function detectSpdxId(content) {
+  const head = content.slice(0, SCAN_BYTES)
+  for (const { spdx, re } of LICENSE_PATTERNS) {
+    if (re.test(head)) return spdx
+  }
+  return undefined
+}
+
+export { description, httpErrorsFor, detectSpdxId }

services/tangled/tangled-license.service.js

@@ -0,0 +1,55 @@
+import { BaseService, NotFound, pathParams } from '../index.js'
+import { renderLicenseBadge } from '../licenses.js'
+import { description, detectSpdxId, httpErrorsFor } from './tangled-helper.js'
+
+const CANDIDATE_PATHS = [
+  'LICENSE',
+  'LICENSE.md',
+  'LICENSE.txt',
+  'COPYING',
+  'COPYING.md',
+]
+
+export default class TangledLicense extends BaseService {
+  static category = 'license'
+  static route = { base: 'tangled/l', pattern: ':owner/:repo' }
+  static openApi = {
+    '/tangled/l/{owner}/{repo}': {
+      get: {
+        summary: 'Tangled License',
+        description,
+        parameters: pathParams(
+          { name: 'owner', example: 'tangled.org' },
+          { name: 'repo', example: 'core' },
+        ),
+      },
+    },
+  }
+
+  static defaultBadgeData = { label: 'license' }
+
+  static render({ license }) {
+    if (license === undefined) return { message: 'unknown' }
+    if (license === null) return { message: 'not specified' }
+    return renderLicenseBadge({ license })
+  }
+
+  async handle({ owner, repo }) {
+    const httpErrors = httpErrorsFor('repo not found')
+    for (const path of CANDIDATE_PATHS) {
+      try {
+        const { buffer } = await this._request({
+          url: `https://tangled.org/${owner}/${repo}/raw/HEAD/${path}`,
+          httpErrors,
+        })
+        return this.constructor.render({
+          license: detectSpdxId(buffer.toString()),
+        })
+      } catch (e) {
+        if (e instanceof NotFound) continue
+        throw e
+      }
+    }
+    return this.constructor.render({ license: null })
+  }
+}

services/tangled/tangled-license.spec.js

@@ -0,0 +1,67 @@
+import { test, given } from 'sazerac'
+import { detectSpdxId } from './tangled-helper.js'
+import TangledLicense from './tangled-license.service.js'
+
+const MIT_TEXT = `MIT License
+
+Copyright (c) 2024 Example
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction,`
+
+const MIT_TEXT_ALT_YEAR = `MIT License
+
+Copyright (c) 2019 Another Author
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction,`
+
+const APACHE_TEXT = `                                 Apache License
+                                                Version 2.0, January 2004
+                           TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION`
+
+const GPL3_TEXT = `                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007`
+
+const BSD3_TEXT = `Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+* Neither the name of the copyright holder nor the names of its
+  contributors may be used to endorse or promote products derived from
+  this software without specific prior written permission.`
+
+const BSD2_TEXT = `Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.`
+
+test(TangledLicense.render, () => {
+  given({ license: undefined }).expect({ message: 'unknown' })
+  given({ license: null }).expect({ message: 'not specified' })
+  given({ license: 'MIT' }).expect({ message: 'MIT', color: 'green' })
+  given({ license: 'Apache-2.0' }).expect({
+    message: 'Apache-2.0',
+    color: 'green',
+  })
+  given({ license: 'GPL-3.0' }).expect({ message: 'GPL-3.0', color: 'orange' })
+})
+
+test(detectSpdxId, () => {
+  given(MIT_TEXT).expect('MIT')
+  given(MIT_TEXT_ALT_YEAR).expect('MIT')
+  given(APACHE_TEXT).expect('Apache-2.0')
+  given(GPL3_TEXT).expect('GPL-3.0')
+  given(BSD3_TEXT).expect('BSD-3-Clause')
+  given(BSD2_TEXT).expect('BSD-2-Clause')
+  given('This is a proprietary software license.').expect(undefined)
+})

services/tangled/tangled-license.tester.js

@@ -0,0 +1,97 @@
+import { licenseToColor } from '../licenses.js'
+import { createServiceTester } from '../tester.js'
+export const t = await createServiceTester()
+
+const mitColor = licenseToColor('MIT')
+const apacheColor = licenseToColor('Apache-2.0')
+const gplColor = licenseToColor('GPL-3.0')
+
+const MIT_BODY = `MIT License
+
+Copyright (c) 2024 Example
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction,`
+
+const APACHE_BODY = `                                 Apache License, Version 2.0
+                           TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION`
+const GPL3_BODY = `                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007`
+
+t.create('MIT license')
+  .get('/testowner/testrepo.json')
+  .intercept(nock =>
+    nock('https://tangled.org')
+      .get('/testowner/testrepo/raw/HEAD/LICENSE')
+      .reply(200, MIT_BODY),
+  )
+  .expectBadge({ label: 'license', message: 'MIT', color: mitColor })
+
+t.create('Apache-2.0 license')
+  .get('/testowner/testrepo.json')
+  .intercept(nock =>
+    nock('https://tangled.org')
+      .get('/testowner/testrepo/raw/HEAD/LICENSE')
+      .reply(200, APACHE_BODY),
+  )
+  .expectBadge({ label: 'license', message: 'Apache-2.0', color: apacheColor })
+
+t.create('GPL-3.0 license')
+  .get('/testowner/testrepo.json')
+  .intercept(nock =>
+    nock('https://tangled.org')
+      .get('/testowner/testrepo/raw/HEAD/LICENSE')
+      .reply(200, GPL3_BODY),
+  )
+  .expectBadge({ label: 'license', message: 'GPL-3.0', color: gplColor })
+
+t.create('unrecognised license body')
+  .get('/testowner/testrepo.json')
+  .intercept(nock =>
+    nock('https://tangled.org')
+      .get('/testowner/testrepo/raw/HEAD/LICENSE')
+      .reply(200, 'All rights reserved. Proprietary and confidential.'),
+  )
+  .expectBadge({ label: 'license', message: 'unknown', color: 'lightgrey' })
+
+t.create('falls through to LICENSE.md when LICENSE is absent')
+  .get('/testowner/testrepo.json')
+  .intercept(nock =>
+    nock('https://tangled.org')
+      .get('/testowner/testrepo/raw/HEAD/LICENSE')
+      .reply(404)
+      .get('/testowner/testrepo/raw/HEAD/LICENSE.md')
+      .reply(200, MIT_BODY),
+  )
+  .expectBadge({ label: 'license', message: 'MIT', color: mitColor })
+
+t.create('no license file found')
+  .get('/testowner/nolicense.json')
+  .intercept(nock =>
+    nock('https://tangled.org')
+      .get('/testowner/nolicense/raw/HEAD/LICENSE')
+      .reply(404)
+      .get('/testowner/nolicense/raw/HEAD/LICENSE.md')
+      .reply(404)
+      .get('/testowner/nolicense/raw/HEAD/LICENSE.txt')
+      .reply(404)
+      .get('/testowner/nolicense/raw/HEAD/COPYING')
+      .reply(404)
+      .get('/testowner/nolicense/raw/HEAD/COPYING.md')
+      .reply(404),
+  )
+  .expectBadge({
+    label: 'license',
+    message: 'not specified',
+    color: 'lightgrey',
+  })
+
+t.create('dotted owner handle (e.g. icyphox.sh)')
+  .get('/icyphox.sh/testrepo.json')
+  .intercept(nock =>
+    nock('https://tangled.org')
+      .get('/icyphox.sh/testrepo/raw/HEAD/LICENSE')
+      .reply(200, MIT_BODY),
+  )
+  .expectBadge({ label: 'license', message: 'MIT', color: mitColor })