downcase subject name for OCI images (#63)

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

__tests__/subject.test.ts

@@ -5,6 +5,10 @@ import path from 'path'
 import { subjectFromInputs } from '../src/subject'
 
 describe('subjectFromInputs', () => {
+  beforeEach(() => {
+    process.env['INPUT_PUSH-TO-REGISTRY'] = 'false'
+  })
+
   afterEach(() => {
     process.env['INPUT_SUBJECT-PATH'] = ''
     process.env['INPUT_SUBJECT-DIGEST'] = ''
@@ -45,12 +49,12 @@ describe('subjectFromInputs', () => {
   })
 
   describe('when specifying a subject digest', () => {
-    const name = 'subject'
+    const name = 'Subject'
 
     describe('when the digest is malformed', () => {
       beforeEach(() => {
         process.env['INPUT_SUBJECT-DIGEST'] = 'digest'
-        process.env['INPUT_SUBJECT-NAME'] = 'subject'
+        process.env['INPUT_SUBJECT-NAME'] = name
       })
 
       it('throws an error', async () => {
@@ -63,7 +67,7 @@ describe('subjectFromInputs', () => {
     describe('when the alogrithm is not supported', () => {
       beforeEach(() => {
         process.env['INPUT_SUBJECT-DIGEST'] = 'md5:deadbeef'
-        process.env['INPUT_SUBJECT-NAME'] = 'subject'
+        process.env['INPUT_SUBJECT-NAME'] = name
       })
 
       it('throws an error', async () => {
@@ -76,7 +80,7 @@ describe('subjectFromInputs', () => {
     describe('when the sha256 digest is malformed', () => {
       beforeEach(() => {
         process.env['INPUT_SUBJECT-DIGEST'] = 'sha256:deadbeef'
-        process.env['INPUT_SUBJECT-NAME'] = 'subject'
+        process.env['INPUT_SUBJECT-NAME'] = name
       })
 
       it('throws an error', async () => {
@@ -105,6 +109,28 @@ describe('subjectFromInputs', () => {
         expect(subject[0].digest).toEqual({ [alg]: digest })
       })
     })
+
+    describe('when the push-to-registry is true', () => {
+      const imageName = 'ghcr.io/FOO/bar'
+      const alg = 'sha256'
+      const digest =
+        '7d070f6b64d9bcc530fe99cc21eaaa4b3c364e0b2d367d7735671fa202a03b32'
+
+      beforeEach(() => {
+        process.env['INPUT_SUBJECT-DIGEST'] = `${alg}:${digest}`
+        process.env['INPUT_SUBJECT-NAME'] = imageName
+        process.env['INPUT_PUSH-TO-REGISTRY'] = 'true'
+      })
+
+      it('returns the subject (with name downcased)', async () => {
+        const subject = await subjectFromInputs()
+
+        expect(subject).toBeDefined()
+        expect(subject).toHaveLength(1)
+        expect(subject[0].name).toEqual(imageName.toLowerCase())
+        expect(subject[0].digest).toEqual({ [alg]: digest })
+      })
+    })
   })
 
   describe('when specifying a subject path', () => {

src/subject.ts

@@ -17,6 +17,9 @@ export const subjectFromInputs = async (): Promise<Subject[]> => {
   const subjectPath = core.getInput('subject-path', { required: false })
   const subjectDigest = core.getInput('subject-digest', { required: false })
   const subjectName = core.getInput('subject-name', { required: false })
+  const pushToRegistry = core.getBooleanInput('push-to-registry', {
+    required: false
+  })
 
   if (!subjectPath && !subjectDigest) {
     throw new Error('One of subject-path or subject-digest must be provided')
@@ -32,10 +35,14 @@ export const subjectFromInputs = async (): Promise<Subject[]> => {
     throw new Error('subject-name must be provided when using subject-digest')
   }
 
+  // If push-to-registry is enabled, ensure the subject name is lowercase
+  // to conform to OCI image naming conventions
+  const name = pushToRegistry ? subjectName.toLowerCase() : subjectName
+
   if (subjectPath) {
-    return await getSubjectFromPath(subjectPath, subjectName)
+    return await getSubjectFromPath(subjectPath, name)
   } else {
-    return [getSubjectFromDigest(subjectDigest, subjectName)]
+    return [getSubjectFromDigest(subjectDigest, name)]
   }
 }