testing

Signed-off-by: Brian DeHamer <bdehamer@github.com>

.github/linters/.eslintrc.yml

@@ -41,7 +41,8 @@ rules:
     'eslint-comments/no-unused-disable': 'off',
     'i18n-text/no-en': 'off',
     'import/no-namespace': 'off',
-    'import/no-unresolved': ['error', { 'ignore': ['csv-parse/sync'] }],
+    'import/no-unresolved':
+      ['error', { 'ignore': ['csv-parse/sync']}],
     'no-console': 'off',
     'no-unused-vars': 'off',
     'prettier/prettier': 'error',

.github/workflows/linter.yml

@@ -38,7 +38,7 @@ jobs:
 
       - name: Lint Codebase
         id: super-linter
-        uses: super-linter/super-linter/slim@v7
+        uses: super-linter/super-linter/slim@v6
         env:
           DEFAULT_BRANCH: main
           FILTER_REGEX_EXCLUDE: dist/**/*

.github/workflows/publish-immutable-actions.yml

@@ -1,22 +0,0 @@
-name: 'Publish Immutable Action Version'
-
-on:
-  release:
-    types: [published]
-
-permissions: {}
-
-jobs:
-  publish:
-    runs-on: ubuntu-latest
-    permissions:
-      contents: read
-      id-token: write
-      packages: write
-
-    steps:
-      - name: Checking out
-        uses: actions/checkout@v4
-      - name: Publish
-        id: publish
-        uses: actions/publish-immutable-action@v0.0.4

README.md

@@ -24,16 +24,6 @@ CLI][5].
 See [Using artifact attestations to establish provenance for builds][9] for more
 information on artifact attestations.
 
-<!-- prettier-ignore-start -->
-> [!NOTE]
-> Artifact attestations are available in public repositories for all
-> current GitHub plans. They are not available on legacy plans, such as Bronze,
-> Silver, or Gold. If you are on a GitHub Free, GitHub Pro, or GitHub Team plan,
-> artifact attestations are only available for public repositories. To use
-> artifact attestations in private or internal repositories, you must be on a
-> GitHub Enterprise Cloud plan.
-<!-- prettier-ignore-end -->
-
 ## Usage
 
 Within the GitHub Actions workflow which builds some artifact you would like to
@@ -54,7 +44,7 @@ attest:
 1. Add the following to your workflow after your artifact has been built:
 
    ```yaml
-   - uses: actions/attest@v2
+   - uses: actions/attest@v1
      with:
        subject-path: '<PATH TO ARTIFACT>'
        predicate-type: '<PREDICATE URI>'
@@ -71,11 +61,11 @@ attest:
 See [action.yml](action.yml)
 
 ```yaml
-- uses: actions/attest@v2
+- uses: actions/attest@v1
   with:
     # Path to the artifact serving as the subject of the attestation. Must
     # specify exactly one of "subject-path" or "subject-digest". May contain
-    # a glob pattern or list of paths (total subject count cannot exceed 1024).
+    # a glob pattern or list of paths (total subject count cannot exceed 2500).
     subject-path:
 
     # SHA256 digest of the subject for the attestation. Must be in the form
@@ -119,24 +109,26 @@ See [action.yml](action.yml)
 
 <!-- markdownlint-disable MD013 -->
 
-| Name              | Description                                                    | Example                                          |
-| ----------------- | -------------------------------------------------------------- | ------------------------------------------------ |
-| `attestation-id`  | GitHub ID for the attestation                                  | `123456`                                         |
-| `attestation-url` | Absolute path to the file containing the generated attestation | `https://github.com/foo/bar/attestations/123456` |
-| `bundle-path`     | Absolute path to the file containing the generated attestation | `/tmp/attestation.json`                          |
+| Name          | Description                                                    | Example                  |
+| ------------- | -------------------------------------------------------------- | ------------------------ |
+| `bundle-path` | Absolute path to the file containing the generated attestation | `/tmp/attestation.jsonl` |
 
 <!-- markdownlint-enable MD013 -->
 
 Attestations are saved in the JSON-serialized [Sigstore bundle][6] format.
 
-If multiple subjects are being attested at the same time, a single attestation
-will be created with references to each of the supplied subjects.
+If multiple subjects are being attested at the same time, each attestation will
+be written to the output file on a separate line (using the [JSON Lines][7]
+format).
 
 ## Attestation Limits
 
 ### Subject Limits
 
-No more than 1024 subjects can be attested at the same time.
+No more than 2500 subjects can be attested at the same time. Subjects will be
+processed in batches 50. After the initial group of 50, each subsequent batch
+will incur an exponentially increasing amount of delay (capped at 1 minute of
+delay per batch) to avoid overwhelming the attestation API.
 
 ### Predicate Limits
 
@@ -169,7 +161,7 @@ jobs:
       - name: Build artifact
         run: make my-app
       - name: Attest
-        uses: actions/attest@v2
+        uses: actions/attest@v1
         with:
           subject-path: '${{ github.workspace }}/my-app'
           predicate-type: 'https://example.com/predicate/v1'
@@ -178,11 +170,11 @@ jobs:
 
 ### Identify Multiple Subjects
 
-If you are generating multiple artifacts, you can attest all of them at the same
-time by using a wildcard in the `subject-path` input.
+If you are generating multiple artifacts, you can generate an attestation for
+each by using a wildcard in the `subject-path` input.
 
 ```yaml
-- uses: actions/attest@v2
+- uses: actions/attest@v1
   with:
     subject-path: 'dist/**/my-bin-*'
     predicate-type: 'https://example.com/predicate/v1'
@@ -196,13 +188,13 @@ Alternatively, you can explicitly list multiple subjects with either a comma or
 newline delimited list:
 
 ```yaml
-- uses: actions/attest@v2
+- uses: actions/attest@v1
   with:
     subject-path: 'dist/foo, dist/bar'
 ```
 
 ```yaml
-- uses: actions/attest@v2
+- uses: actions/attest@v1
   with:
     subject-path: |
       dist/foo
@@ -259,7 +251,7 @@ jobs:
           push: true
           tags: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest
       - name: Attest
-        uses: actions/attest@v2
+        uses: actions/attest@v1
         id: attest
         with:
           subject-name: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
@@ -277,6 +269,7 @@ jobs:
 [5]: https://cli.github.com/manual/gh_attestation_verify
 [6]:
   https://github.com/sigstore/protobuf-specs/blob/main/protos/sigstore_bundle.proto
+[7]: https://jsonlines.org/
 [8]: https://github.com/actions/toolkit/tree/main/packages/glob#patterns
 [9]:
   https://docs.github.com/en/actions/security-guides/using-artifact-attestations-to-establish-provenance-for-builds

__tests__/main.test.ts

@@ -46,7 +46,8 @@ const defaultInputs: main.RunInputs = {
   pushToRegistry: false,
   showSummary: true,
   githubToken: '',
-  privateSigning: false
+  privateSigning: false,
+  batchSize: 50
 }
 
 describe('action', () => {
@@ -197,17 +198,7 @@ describe('action', () => {
       expect(setOutputMock).toHaveBeenNthCalledWith(
         1,
         'bundle-path',
-        expect.stringMatching('attestation.json')
-      )
-      expect(setOutputMock).toHaveBeenNthCalledWith(
-        2,
-        'attestation-id',
-        expect.stringMatching(attestationID)
-      )
-      expect(setOutputMock).toHaveBeenNthCalledWith(
-        3,
-        'attestation-url',
-        expect.stringContaining(`foo/bar/attestations/${attestationID}`)
+        expect.stringMatching('attestation.jsonl')
       )
       expect(setFailedMock).not.toHaveBeenCalled()
     })
@@ -293,27 +284,21 @@ describe('action', () => {
       expect(setOutputMock).toHaveBeenNthCalledWith(
         1,
         'bundle-path',
-        expect.stringMatching('attestation.json')
-      )
-      expect(setOutputMock).toHaveBeenNthCalledWith(
-        2,
-        'attestation-id',
-        expect.stringMatching(attestationID)
-      )
-      expect(setOutputMock).toHaveBeenNthCalledWith(
-        3,
-        'attestation-url',
-        expect.stringContaining(`foo/bar/attestations/${attestationID}`)
+        expect.stringMatching('attestation.jsonl')
       )
       expect(setFailedMock).not.toHaveBeenCalled()
     })
   })
 
-  describe('when the subject count is greater than 1', () => {
+  describe('when the subject count exceeds the batch size', () => {
     let dir = ''
     const filename = 'subject'
+    let scope: nock.Scope
 
     beforeEach(async () => {
+      // Start from scratch
+      nock.cleanAll()
+
       const subjectCount = 5
       const content = 'file content'
 
@@ -324,22 +309,38 @@ describe('action', () => {
       // Add files for glob testing
       for (let i = 0; i < subjectCount; i++) {
         await fs.writeFile(path.join(dir, `${filename}-${i}`), content)
+
+        // Set-up a Fulcio mock for each subject
+        await mockFulcio({
+          baseURL: 'https://fulcio.githubapp.com',
+          strict: false
+        })
+
+        // Set-up a TSA mock for each subject
+        await mockTSA({ baseURL: 'https://timestamp.githubapp.com' })
+
+        // Set-up a GH API mock for each subject
+        mockAgent
+          .get('https://api.github.com')
+          .intercept({
+            path: /^\/repos\/.*\/.*\/attestations$/,
+            method: 'post'
+          })
+          .reply(201, { id: attestationID })
       }
 
+      // Set-up a OIDC token mock for each subject
+      scope = nock(tokenURL)
+        .get('/')
+        .query({ audience: 'sigstore' })
+        .times(subjectCount)
+        .reply(200, { value: oidcToken })
+
       // Set the GH context with private repository visibility and a repo owner.
       setGHContext({
         payload: { repository: { visibility: 'private' } },
         repo: { owner: 'foo', repo: 'bar' }
       })
-
-      // Set-up a Fulcio mock for each subject
-      await mockFulcio({
-        baseURL: 'https://fulcio.githubapp.com',
-        strict: false
-      })
-
-      // Set-up a TSA mock for each subject
-      await mockTSA({ baseURL: 'https://timestamp.githubapp.com' })
     })
 
     afterEach(async () => {
@@ -353,7 +354,8 @@ describe('action', () => {
         subjectPath: path.join(dir, `${filename}-*`),
         predicateType,
         predicate,
-        githubToken: 'gh-token'
+        githubToken: 'gh-token',
+        batchSize: 2
       }
       await main.run(inputs)
 
@@ -361,8 +363,17 @@ describe('action', () => {
       expect(setFailedMock).not.toHaveBeenCalled()
       expect(infoMock).toHaveBeenNthCalledWith(
         1,
-        expect.stringMatching('Attestation created for 5 subjects')
+        expect.stringMatching('Processing subject batch 1/3')
       )
+      expect(infoMock).toHaveBeenNthCalledWith(
+        10,
+        expect.stringMatching('Processing subject batch 2/3')
+      )
+      expect(infoMock).toHaveBeenNthCalledWith(
+        19,
+        expect.stringMatching('Processing subject batch 3/3')
+      )
+      expect(scope.isDone()).toBe(true)
     })
   })
 
@@ -371,7 +382,7 @@ describe('action', () => {
     const filename = 'subject'
 
     beforeEach(async () => {
-      const subjectCount = 1025
+      const subjectCount = 2501
       const content = 'file content'
 
       // Set-up temp directory
@@ -408,7 +419,7 @@ describe('action', () => {
       expect(runMock).toHaveReturned()
       expect(setFailedMock).toHaveBeenCalledWith(
         new Error(
-          'Too many subjects specified. The maximum number of subjects is 1024.'
+          'Too many subjects specified. The maximum number of subjects is 2500.'
         )
       )
     })

__tests__/subject.test.ts

@@ -2,11 +2,7 @@ import crypto from 'crypto'
 import fs from 'fs/promises'
 import os from 'os'
 import path from 'path'
-import {
-  formatSubjectDigest,
-  subjectFromInputs,
-  SubjectInputs
-} from '../src/subject'
+import { subjectFromInputs, SubjectInputs } from '../src/subject'
 
 describe('subjectFromInputs', () => {
   const blankInputs: SubjectInputs = {
@@ -362,42 +358,5 @@ describe('subjectFromInputs', () => {
         })
       })
     })
-
-    describe('when duplicate subjects are supplied', () => {
-      let otherDir = ''
-
-      // Add duplicate subject in alternate directory
-      beforeEach(async () => {
-        // Set-up temp directory
-        const tmpDir = await fs.realpath(os.tmpdir())
-        otherDir = await fs.mkdtemp(tmpDir + path.sep)
-
-        // Write file to temp directory
-        await fs.writeFile(path.join(otherDir, filename), content)
-      })
-
-      it('returns de-duplicated subjects', async () => {
-        const inputs: SubjectInputs = {
-          ...blankInputs,
-          subjectPath: `${path.join(dir, 'subject')}, ${path.join(otherDir, 'subject')} `
-        }
-        const subjects = await subjectFromInputs(inputs)
-
-        expect(subjects).toBeDefined()
-        expect(subjects).toHaveLength(1)
-      })
-    })
-  })
-})
-
-describe('subjectDigest', () => {
-  it('returns the digest', () => {
-    const subject = {
-      name: 'foo',
-      digest: { sha1: 'deadbeef' }
-    }
-
-    const digest = formatSubjectDigest(subject)
-    expect(digest).toEqual('sha1:deadbeef')
   })
 })

action.yml

@@ -10,7 +10,7 @@ inputs:
     description: >
       Path to the artifact serving as the subject of the attestation. Must
       specify exactly one of "subject-path" or "subject-digest". May contain a
-      glob pattern or list of paths (total subject count cannot exceed 1024).
+      glob pattern or list of paths (total subject count cannot exceed 2500).
     required: false
   subject-digest:
     description: >
@@ -60,11 +60,7 @@ inputs:
     required: false
 outputs:
   bundle-path:
-    description: 'The path to the file containing the attestation bundle.'
-  attestation-id:
-    description: 'The ID of the attestation.'
-  attestation-url:
-    description: 'The URL for the attestation summary.'
+    description: 'The path to the file containing the attestation bundle(s).'
 
 runs:
   using: node20

dist/606.index.js

@@ -1,287 +0,0 @@
-"use strict";
-exports.id = 606;
-exports.ids = [606];
-exports.modules = {
-
-/***/ 606:
-/***/ ((__unused_webpack___webpack_module__, __webpack_exports__, __webpack_require__) => {
-
-/* harmony export */ __webpack_require__.d(__webpack_exports__, {
-/* harmony export */   "default": () => (/* binding */ pMap)
-/* harmony export */ });
-/* unused harmony exports pMapIterable, pMapSkip */
-async function pMap(
-	iterable,
-	mapper,
-	{
-		concurrency = Number.POSITIVE_INFINITY,
-		stopOnError = true,
-		signal,
-	} = {},
-) {
-	return new Promise((resolve, reject_) => {
-		if (iterable[Symbol.iterator] === undefined && iterable[Symbol.asyncIterator] === undefined) {
-			throw new TypeError(`Expected \`input\` to be either an \`Iterable\` or \`AsyncIterable\`, got (${typeof iterable})`);
-		}
-
-		if (typeof mapper !== 'function') {
-			throw new TypeError('Mapper function is required');
-		}
-
-		if (!((Number.isSafeInteger(concurrency) && concurrency >= 1) || concurrency === Number.POSITIVE_INFINITY)) {
-			throw new TypeError(`Expected \`concurrency\` to be an integer from 1 and up or \`Infinity\`, got \`${concurrency}\` (${typeof concurrency})`);
-		}
-
-		const result = [];
-		const errors = [];
-		const skippedIndexesMap = new Map();
-		let isRejected = false;
-		let isResolved = false;
-		let isIterableDone = false;
-		let resolvingCount = 0;
-		let currentIndex = 0;
-		const iterator = iterable[Symbol.iterator] === undefined ? iterable[Symbol.asyncIterator]() : iterable[Symbol.iterator]();
-
-		const reject = reason => {
-			isRejected = true;
-			isResolved = true;
-			reject_(reason);
-		};
-
-		if (signal) {
-			if (signal.aborted) {
-				reject(signal.reason);
-			}
-
-			signal.addEventListener('abort', () => {
-				reject(signal.reason);
-			});
-		}
-
-		const next = async () => {
-			if (isResolved) {
-				return;
-			}
-
-			const nextItem = await iterator.next();
-
-			const index = currentIndex;
-			currentIndex++;
-
-			// Note: `iterator.next()` can be called many times in parallel.
-			// This can cause multiple calls to this `next()` function to
-			// receive a `nextItem` with `done === true`.
-			// The shutdown logic that rejects/resolves must be protected
-			// so it runs only one time as the `skippedIndex` logic is
-			// non-idempotent.
-			if (nextItem.done) {
-				isIterableDone = true;
-
-				if (resolvingCount === 0 && !isResolved) {
-					if (!stopOnError && errors.length > 0) {
-						reject(new AggregateError(errors)); // eslint-disable-line unicorn/error-message
-						return;
-					}
-
-					isResolved = true;
-
-					if (skippedIndexesMap.size === 0) {
-						resolve(result);
-						return;
-					}
-
-					const pureResult = [];
-
-					// Support multiple `pMapSkip`'s.
-					for (const [index, value] of result.entries()) {
-						if (skippedIndexesMap.get(index) === pMapSkip) {
-							continue;
-						}
-
-						pureResult.push(value);
-					}
-
-					resolve(pureResult);
-				}
-
-				return;
-			}
-
-			resolvingCount++;
-
-			// Intentionally detached
-			(async () => {
-				try {
-					const element = await nextItem.value;
-
-					if (isResolved) {
-						return;
-					}
-
-					const value = await mapper(element, index);
-
-					// Use Map to stage the index of the element.
-					if (value === pMapSkip) {
-						skippedIndexesMap.set(index, value);
-					}
-
-					result[index] = value;
-
-					resolvingCount--;
-					await next();
-				} catch (error) {
-					if (stopOnError) {
-						reject(error);
-					} else {
-						errors.push(error);
-						resolvingCount--;
-
-						// In that case we can't really continue regardless of `stopOnError` state
-						// since an iterable is likely to continue throwing after it throws once.
-						// If we continue calling `next()` indefinitely we will likely end up
-						// in an infinite loop of failed iteration.
-						try {
-							await next();
-						} catch (error) {
-							reject(error);
-						}
-					}
-				}
-			})();
-		};
-
-		// Create the concurrent runners in a detached (non-awaited)
-		// promise. We need this so we can await the `next()` calls
-		// to stop creating runners before hitting the concurrency limit
-		// if the iterable has already been marked as done.
-		// NOTE: We *must* do this for async iterators otherwise we'll spin up
-		// infinite `next()` calls by default and never start the event loop.
-		(async () => {
-			for (let index = 0; index < concurrency; index++) {
-				try {
-					// eslint-disable-next-line no-await-in-loop
-					await next();
-				} catch (error) {
-					reject(error);
-					break;
-				}
-
-				if (isIterableDone || isRejected) {
-					break;
-				}
-			}
-		})();
-	});
-}
-
-function pMapIterable(
-	iterable,
-	mapper,
-	{
-		concurrency = Number.POSITIVE_INFINITY,
-		backpressure = concurrency,
-	} = {},
-) {
-	if (iterable[Symbol.iterator] === undefined && iterable[Symbol.asyncIterator] === undefined) {
-		throw new TypeError(`Expected \`input\` to be either an \`Iterable\` or \`AsyncIterable\`, got (${typeof iterable})`);
-	}
-
-	if (typeof mapper !== 'function') {
-		throw new TypeError('Mapper function is required');
-	}
-
-	if (!((Number.isSafeInteger(concurrency) && concurrency >= 1) || concurrency === Number.POSITIVE_INFINITY)) {
-		throw new TypeError(`Expected \`concurrency\` to be an integer from 1 and up or \`Infinity\`, got \`${concurrency}\` (${typeof concurrency})`);
-	}
-
-	if (!((Number.isSafeInteger(backpressure) && backpressure >= concurrency) || backpressure === Number.POSITIVE_INFINITY)) {
-		throw new TypeError(`Expected \`backpressure\` to be an integer from \`concurrency\` (${concurrency}) and up or \`Infinity\`, got \`${backpressure}\` (${typeof backpressure})`);
-	}
-
-	return {
-		async * [Symbol.asyncIterator]() {
-			const iterator = iterable[Symbol.asyncIterator] === undefined ? iterable[Symbol.iterator]() : iterable[Symbol.asyncIterator]();
-
-			const promises = [];
-			let runningMappersCount = 0;
-			let isDone = false;
-			let index = 0;
-
-			function trySpawn() {
-				if (isDone || !(runningMappersCount < concurrency && promises.length < backpressure)) {
-					return;
-				}
-
-				const promise = (async () => {
-					const {done, value} = await iterator.next();
-
-					if (done) {
-						return {done: true};
-					}
-
-					runningMappersCount++;
-
-					// Spawn if still below concurrency and backpressure limit
-					trySpawn();
-
-					try {
-						const returnValue = await mapper(await value, index++);
-
-						runningMappersCount--;
-
-						if (returnValue === pMapSkip) {
-							const index = promises.indexOf(promise);
-
-							if (index > 0) {
-								promises.splice(index, 1);
-							}
-						}
-
-						// Spawn if still below backpressure limit and just dropped below concurrency limit
-						trySpawn();
-
-						return {done: false, value: returnValue};
-					} catch (error) {
-						isDone = true;
-						return {error};
-					}
-				})();
-
-				promises.push(promise);
-			}
-
-			trySpawn();
-
-			while (promises.length > 0) {
-				const {error, done, value} = await promises[0]; // eslint-disable-line no-await-in-loop
-
-				promises.shift();
-
-				if (error) {
-					throw error;
-				}
-
-				if (done) {
-					return;
-				}
-
-				// Spawn if just dropped below backpressure limit and below the concurrency limit
-				trySpawn();
-
-				if (value === pMapSkip) {
-					continue;
-				}
-
-				yield value;
-			}
-		},
-	};
-}
-
-const pMapSkip = Symbol('skip');
-
-
-/***/ })
-
-};
-;

package.json

@@ -1,7 +1,7 @@
 {
   "name": "actions/attest",
   "description": "Generate signed attestations for workflow artifacts",
-  "version": "2.1.0",
+  "version": "1.4.0",
   "author": "",
   "private": true,
   "homepage": "https://github.com/actions/attest",
@@ -69,33 +69,33 @@
     ]
   },
   "dependencies": {
-    "@actions/attest": "^1.5.0",
-    "@actions/core": "^1.11.1",
-    "@actions/glob": "^0.5.0",
-    "@sigstore/oci": "^0.4.0",
-    "csv-parse": "^5.6.0"
+    "@actions/attest": "^1.3.1",
+    "@actions/core": "^1.10.1",
+    "@actions/glob": "^0.4.0",
+    "@sigstore/oci": "^0.3.7",
+    "csv-parse": "^5.5.6"
   },
   "devDependencies": {
-    "@sigstore/mock": "^0.8.0",
-    "@types/jest": "^29.5.14",
+    "@sigstore/mock": "^0.7.5",
+    "@types/jest": "^29.5.12",
     "@types/make-fetch-happen": "^10.0.4",
-    "@types/node": "^22.9.4",
+    "@types/node": "^22.2.0",
     "@typescript-eslint/eslint-plugin": "^7.18.0",
     "@typescript-eslint/parser": "^7.18.0",
-    "@vercel/ncc": "^0.38.3",
-    "eslint": "^8.57.1",
-    "eslint-plugin-github": "^5.1.2",
-    "eslint-plugin-jest": "^28.9.0",
-    "eslint-plugin-jsonc": "^2.18.2",
+    "@vercel/ncc": "^0.38.1",
+    "eslint": "^8.57.0",
+    "eslint-plugin-github": "^5.0.1",
+    "eslint-plugin-jest": "^28.8.0",
+    "eslint-plugin-jsonc": "^2.16.0",
     "eslint-plugin-prettier": "^5.2.1",
     "jest": "^29.7.0",
     "js-yaml": "^4.1.0",
-    "markdownlint-cli": "^0.43.0",
-    "nock": "^13.5.6",
+    "markdownlint-cli": "^0.41.0",
+    "nock": "^13.5.4",
     "prettier": "^3.3.3",
     "prettier-eslint": "^16.3.0",
-    "ts-jest": "^29.2.5",
-    "typescript": "^5.7.2",
+    "ts-jest": "^29.2.4",
+    "typescript": "^5.5.4",
     "undici": "^5.28.4"
   }
 }

src/attest.ts

@@ -1,17 +1,18 @@
 import { Attestation, Predicate, Subject, attest } from '@actions/attest'
 import { attachArtifactToImage, getRegistryCredentials } from '@sigstore/oci'
-import { formatSubjectDigest } from './subject'
 
 const OCI_TIMEOUT = 30000
 const OCI_RETRY = 3
 
 export type SigstoreInstance = 'public-good' | 'github'
 export type AttestResult = Attestation & {
+  subjectName: string
+  subjectDigest: string
   attestationDigest?: string
 }
 
 export const createAttestation = async (
-  subjects: Subject[],
+  subject: Subject,
   predicate: Predicate,
   opts: {
     sigstoreInstance: SigstoreInstance
@@ -21,22 +22,27 @@ export const createAttestation = async (
 ): Promise<AttestResult> => {
   // Sign provenance w/ Sigstore
   const attestation = await attest({
-    subjects,
+    subjectName: subject.name,
+    subjectDigest: subject.digest,
     predicateType: predicate.type,
     predicate: predicate.params,
     sigstore: opts.sigstoreInstance,
     token: opts.githubToken
   })
 
-  const result: AttestResult = attestation
+  const subDigest = subjectDigest(subject)
+  const result: AttestResult = {
+    ...attestation,
+    subjectName: subject.name,
+    subjectDigest: subDigest
+  }
 
-  if (subjects.length === 1 && opts.pushToRegistry) {
-    const subject = subjects[0]
+  if (opts.pushToRegistry) {
     const credentials = getRegistryCredentials(subject.name)
     const artifact = await attachArtifactToImage({
       credentials,
       imageName: subject.name,
-      imageDigest: formatSubjectDigest(subject),
+      imageDigest: subDigest,
       artifact: Buffer.from(JSON.stringify(attestation.bundle)),
       mediaType: attestation.bundle.mediaType,
       annotations: {
@@ -52,3 +58,10 @@ export const createAttestation = async (
 
   return result
 }
+
+// Returns the subject's digest as a formatted string of the form
+// "<algorithm>:<digest>".
+const subjectDigest = (subject: Subject): string => {
+  const alg = Object.keys(subject.digest).sort()[0]
+  return `${alg}:${subject.digest[alg]}`
+}

src/index.ts

@@ -4,6 +4,8 @@
 import * as core from '@actions/core'
 import { run, RunInputs } from './main'
 
+const DEFAULT_BATCH_SIZE = 50
+
 const inputs: RunInputs = {
   subjectPath: core.getInput('subject-path'),
   subjectName: core.getInput('subject-name'),
@@ -17,7 +19,9 @@ const inputs: RunInputs = {
   // undocumented -- not part of public interface
   privateSigning: ['true', 'True', 'TRUE', '1'].includes(
     core.getInput('private-signing')
-  )
+  ),
+  // internal only
+  batchSize: DEFAULT_BATCH_SIZE
 }
 
 // eslint-disable-next-line @typescript-eslint/no-floating-promises

src/main.ts

@@ -7,15 +7,11 @@ import { AttestResult, SigstoreInstance, createAttestation } from './attest'
 import { SEARCH_PUBLIC_GOOD_URL } from './endpoints'
 import { PredicateInputs, predicateFromInputs } from './predicate'
 import * as style from './style'
-import {
-  SubjectInputs,
-  formatSubjectDigest,
-  subjectFromInputs
-} from './subject'
+import { SubjectInputs, subjectFromInputs } from './subject'
 
-import type { Subject } from '@actions/attest'
-
-const ATTESTATION_FILE_NAME = 'attestation.json'
+const ATTESTATION_FILE_NAME = 'attestation.jsonl'
+const DELAY_INTERVAL_MS = 75
+const DELAY_MAX_MS = 1200
 
 export type RunInputs = SubjectInputs &
   PredicateInputs & {
@@ -23,6 +19,7 @@ export type RunInputs = SubjectInputs &
     githubToken: string
     showSummary: boolean
     privateSigning: boolean
+    batchSize: number
   }
 
 /* istanbul ignore next */
@@ -50,6 +47,7 @@ export async function run(inputs: RunInputs): Promise<void> {
       : 'github'
 
   try {
+    const atts: AttestResult[] = []
     if (!process.env.ACTIONS_ID_TOKEN_REQUEST_URL) {
       throw new Error(
         'missing "id-token" permission. Please add "permissions: id-token: write" to your workflow.'
@@ -65,27 +63,42 @@ export async function run(inputs: RunInputs): Promise<void> {
     const outputPath = path.join(tempDir(), ATTESTATION_FILE_NAME)
     core.setOutput('bundle-path', outputPath)
 
-    const att = await createAttestation(subjects, predicate, {
-      sigstoreInstance,
-      pushToRegistry: inputs.pushToRegistry,
-      githubToken: inputs.githubToken
-    })
+    const subjectChunks = chunkArray(subjects, inputs.batchSize)
 
-    logAttestation(subjects, att, sigstoreInstance)
+    // Generate attestations for each subject serially, working in batches
+    for (let i = 0; i < subjectChunks.length; i++) {
+      if (subjectChunks.length > 1) {
+        core.info(`Processing subject batch ${i + 1}/${subjectChunks.length}`)
+      }
 
-    // Write attestation bundle to output file
-    fs.writeFileSync(outputPath, JSON.stringify(att.bundle) + os.EOL, {
-      encoding: 'utf-8',
-      flag: 'a'
-    })
+      // Calculate the delay time for this batch
+      const delayTime = delay(i)
 
-    if (att.attestationID) {
-      core.setOutput('attestation-id', att.attestationID)
-      core.setOutput('attestation-url', attestationURL(att.attestationID))
+      for (const subject of subjectChunks[i]) {
+        // Delay between attestations (only when chunk size > 1)
+        if (i > 0) {
+          await new Promise(resolve => setTimeout(resolve, delayTime))
+        }
+
+        const att = await createAttestation(subject, predicate, {
+          sigstoreInstance,
+          pushToRegistry: inputs.pushToRegistry,
+          githubToken: inputs.githubToken
+        })
+        atts.push(att)
+
+        logAttestation(att, sigstoreInstance)
+
+        // Write attestation bundle to output file
+        fs.writeFileSync(outputPath, JSON.stringify(att.bundle) + os.EOL, {
+          encoding: 'utf-8',
+          flag: 'a'
+        })
+      }
     }
 
     if (inputs.showSummary) {
-      logSummary(att)
+      logSummary(atts)
     }
   } catch (err) {
     // Fail the workflow run if an error occurs
@@ -110,17 +123,12 @@ export async function run(inputs: RunInputs): Promise<void> {
 
 // Log details about the attestation to the GitHub Actions run
 const logAttestation = (
-  subjects: Subject[],
   attestation: AttestResult,
   sigstoreInstance: SigstoreInstance
 ): void => {
-  if (subjects.length === 1) {
-    core.info(
-      `Attestation created for ${subjects[0].name}@${formatSubjectDigest(subjects[0])}`
-    )
-  } else {
-    core.info(`Attestation created for ${subjects.length} subjects`)
-  }
+  core.info(
+    `Attestation created for ${attestation.subjectName}@${attestation.subjectDigest}`
+  )
 
   const instanceName =
     sigstoreInstance === 'public-good' ? 'Public Good' : 'GitHub'
@@ -148,18 +156,29 @@ const logAttestation = (
 
   if (attestation.attestationDigest) {
     core.info(style.highlight('Attestation uploaded to registry'))
-    core.info(`${subjects[0].name}@${attestation.attestationDigest}`)
+    core.info(`${attestation.subjectName}@${attestation.attestationDigest}`)
   }
 }
 
 // Attach summary information to the GitHub Actions run
-const logSummary = (attestation: AttestResult): void => {
-  const { attestationID } = attestation
+const logSummary = (attestations: AttestResult[]): void => {
+  if (attestations.length > 0) {
+    core.summary.addHeading(
+      /* istanbul ignore next */
+      attestations.length > 1 ? 'Attestations Created' : 'Attestation Created',
+      3
+    )
 
-  if (attestationID) {
-    const url = attestationURL(attestationID)
-    core.summary.addHeading('Attestation Created', 3)
-    core.summary.addList([`<a href="${url}">${url}</a>`])
+    const listItems = []
+    for (const { subjectName, subjectDigest, attestationID } of attestations) {
+      if (attestationID) {
+        listItems.push(
+          `<a href="${attestationURL(attestationID)}">${subjectName}@${subjectDigest}</a>`
+        )
+      }
+    }
+
+    core.summary.addList(listItems)
     core.summary.write()
   }
 }
@@ -175,5 +194,18 @@ const tempDir = (): string => {
   return fs.mkdtempSync(path.join(basePath, path.sep))
 }
 
+// Transforms an array into an array of arrays, each containing at most
+// `chunkSize` elements.
+const chunkArray = <T>(array: T[], chunkSize: number): T[][] => {
+  return Array.from(
+    { length: Math.ceil(array.length / chunkSize) },
+    (_, index) => array.slice(index * chunkSize, (index + 1) * chunkSize)
+  )
+}
+
+// Calculate the delay time for a given iteration
+const delay = (iteration: number): number =>
+  Math.min(DELAY_INTERVAL_MS * 2 ** iteration, DELAY_MAX_MS)
+
 const attestationURL = (id: string): string =>
   `${github.context.serverUrl}/${github.context.repo.owner}/${github.context.repo.repo}/attestations/${id}`

src/subject.ts

@@ -6,7 +6,7 @@ import path from 'path'
 
 import type { Subject } from '@actions/attest'
 
-const MAX_SUBJECT_COUNT = 1024
+const MAX_SUBJECT_COUNT = 2500
 const DIGEST_ALGORITHM = 'sha256'
 
 export type SubjectInputs = {
@@ -49,13 +49,6 @@ export const subjectFromInputs = async (
   }
 }
 
-// Returns the subject's digest as a formatted string of the form
-// "<algorithm>:<digest>".
-export const formatSubjectDigest = (subject: Subject): string => {
-  const alg = Object.keys(subject.digest).sort()[0]
-  return `${alg}:${subject.digest[alg]}`
-}
-
 // Returns the subject specified by the path to a file. The file's digest is
 // calculated and returned along with the subject's name.
 const getSubjectFromPath = async (
@@ -67,12 +60,9 @@ const getSubjectFromPath = async (
   // Parse the list of subject paths
   const subjectPaths = parseList(subjectPath).join('\n')
 
-  // Expand the globbed paths to a list of actual paths
+  // Expand the globbed paths to a list of files
   /* eslint-disable-next-line github/no-then */
-  const paths = await glob.create(subjectPaths).then(async g => g.glob())
-
-  // Filter path list to just the files (not directories)
-  const files = paths.filter(p => fs.statSync(p).isFile())
+  const files = await glob.create(subjectPaths).then(async g => g.glob())
 
   if (files.length > MAX_SUBJECT_COUNT) {
     throw new Error(
@@ -81,17 +71,15 @@ const getSubjectFromPath = async (
   }
 
   for (const file of files) {
+    // Skip anything that is NOT a file
+    if (!fs.statSync(file).isFile()) {
+      continue
+    }
+
     const name = subjectName || path.parse(file).base
     const digest = await digestFile(DIGEST_ALGORITHM, file)
 
-    // Only add the subject if it is not already in the list
-    if (
-      !digestedSubjects.some(
-        s => s.name === name && s.digest[DIGEST_ALGORITHM] === digest
-      )
-    ) {
-      digestedSubjects.push({ name, digest: { [DIGEST_ALGORITHM]: digest } })
-    }
+    digestedSubjects.push({ name, digest: { [DIGEST_ALGORITHM]: digest } })
   }
 
   if (digestedSubjects.length === 0) {