Initial commit version

README.md

@@ -78,6 +78,7 @@ Inputs can be used to customize the behavior of the action in both modes.
 
 | Name | Description |
 | ---- | ----------- |
+| `initial-version` | If defined when run against the first commit of a new repository (e.g. a templatized repository), idempotently tags that commit with this version number. |
 | `mode` | ***Required.*** `validate` or `bump`. |
 | `repo-token` | ***Required.*** The `GITHUB_TOKEN` for the repo. Needed for fetching pull request data and tagging new releases. |
 | `major-label` | The name of the label that indicates the pull request should result in a **major** version bump. _Default: 'major release'_. |

config.js

@@ -1,6 +1,21 @@
 const core = require('@actions/core')
 const github = require('@actions/github')
 
+// Gets and validates the 'initial-version' input
+function getInitialVersion() {
+    const initialVersion = core.getInput('initial-version')
+    if (initialVersion === undefined || initialVersion === '') {
+        return undefined
+    }
+
+    const match = initialVersion.match(/^v?(\d+\.\d+\.\d+)$/)
+    if (match) {
+        return match[1]
+    }
+
+    throw new Error('initial-version must be in one of the following forms: X.Y.Z or vX.Y.Z')
+}
+
 // Gets all the required inputs and validates them before proceeding.
 function getConfig() {
     const mode = core.getInput('mode', { required: true }).toLowerCase()
@@ -30,6 +45,7 @@ function getConfig() {
     releaseLabels[core.getInput('patch-label') || 'patch release'] = 'patch'
 
     return {
+        initialVersion: getInitialVersion(),
         mode: mode,
         octokit: github.getOctokit(token),
         releaseLabels: releaseLabels,

config.test.js

@@ -22,6 +22,7 @@ test('establishes config from minimum required inputs', () => {
 })
 
 test('establishes config from complete set of inputs', () => {
+    process.env['INPUT_INITIAL-VERSION'] = 'v1.2.3'
     process.env['INPUT_MODE'] = 'validate'
     process.env['INPUT_REPO-TOKEN'] = 'mockRepoToken'
     process.env['INPUT_MAJOR-LABEL'] = 'major-label-name'
@@ -33,6 +34,7 @@ test('establishes config from complete set of inputs', () => {
     process.env['INPUT_WITH-V'] = 'true'
 
     const config = getConfig()
+    expect(config.initialVersion).toBe('1.2.3')
     expect(config.mode).toBe('validate')
     expect(config.releaseLabels).toEqual({
         'major-label-name': 'major',
@@ -53,6 +55,12 @@ test('throws when a required input is missing', () => {
     expect(getConfig).toThrow('Input required and not supplied: mode')
 })
 
+test('errors out when an invalid initial-version is specified', () => {
+    process.env['INPUT_INITIAL-VERSION'] = 'invalid'
+    process.env['INPUT_MODE'] = 'bump'
+    expect(getConfig).toThrow('initial-version must be in one of the following forms: X.Y.Z or vX.Y.Z')
+})
+
 test('errors out when an invalid mode is specified', () => {
     process.env['INPUT_MODE'] = 'invalid'
     process.env['INPUT_REPO-TOKEN'] = 'mockRepoToken'

index.js

@@ -16,6 +16,21 @@ function isActivePR() {
     return github.context.eventName === 'pull_request' && github.context.payload.pull_request !== undefined
 }
 
+// Returns true if an initial version is configured
+// and the current commit is the repository's initial commit.
+async function isInitialVersion(config) {
+    if (config.initialVersion === undefined) {
+        return false
+    }
+
+    const commit = await config.octokit.git.getCommit({
+        ...github.context.repo,
+        commit_sha: github.context.sha,
+    })
+
+    return commit.data.parents.length === 0
+}
+
 // Returns true if the current context looks like a merge commit.
 function isMergeCommit() {
     return github.context.eventName === 'push' && github.context.payload.head_commit !== undefined
@@ -60,36 +75,50 @@ async function validateActivePR(config) {
 
 // Increments the version according to the release type and tags a new version with release notes.
 async function bumpAndTagNewVersion(config) {
-    if (!isMergeCommit()) {
-        core.warning("in 'bump' mode, but this doesn't look like a PR merge commit event (is your workflow misconfigured?)")
-        return
-    }
+    let currentVersion
+    let idempotent = false
+    let newVersion
+    let releaseNotes
+    let releaseType
 
-    const num = extractPRNumber(github.context.payload.head_commit.message)
-    let pr
-    if (num == null) {
-        core.info('Unable to determine PR from commit msg, searching for PR by SHA')
-        // Try to search the commit sha for the PR number
-        pr = await searchPRByCommit(process.env.GITHUB_SHA, config)
-        if (pr == null) {
-            // Don't want to fail the job if some other commit comes in, but let's warn about it.
-            // Might be a good point for configuration in the future.
-            core.warning("head commit doesn't look like a PR merge, skipping version bumping and tagging")
-            return
+    if (isMergeCommit()) {
+        const num = extractPRNumber(github.context.payload.head_commit.message)
+        let pr
+        if (num == null) {
+            core.info('Unable to determine PR from commit msg, searching for PR by SHA')
+            // Try to search the commit sha for the PR number
+            pr = await searchPRByCommit(process.env.GITHUB_SHA, config)
+            if (pr == null) {
+                // Don't want to fail the job if some other commit comes in,
+                // but let's warn about it. Might be a good point for configuration
+                // in the future.
+                core.warning("head commit doesn't look like a PR merge, skipping version bumping and tagging")
+                return
+            }
+        } else {
+            pr = await fetchPR(num, config)
         }
+        core.info(`Processing version bump for PR request #${pr.number}`)
+        releaseType = getReleaseType(pr, config)
+        releaseNotes = getReleaseNotes(pr, config)
+        currentVersion = await getCurrentVersion(config)
+        newVersion = semver.inc(currentVersion, releaseType)
+    } else if (isInitialVersion(config)) {
+        idempotent = true
+        releaseNotes = 'Initial commit'
+        newVersion = config.initialVersion
     } else {
-        pr = await fetchPR(num, config)
+        core.warning("in 'bump' mode, but this doesn't look like a PR merge commit event (is your workflow misconfigured?)")
+        return
     }
-    core.info(`Processing version bump for PR request #${pr.number}`)
-    const releaseType = getReleaseType(pr, config)
-    const releaseNotes = getReleaseNotes(pr, config)
-    const currentVersion = await getCurrentVersion(config)
 
-    const newVersion = semver.inc(currentVersion, releaseType)
-    const newTag = await createRelease(newVersion, releaseNotes, config)
+    const newTag = await createRelease(newVersion, releaseNotes, config, idempotent)
     core.info(`Created release tag ${newTag} with the following release notes:\n${releaseNotes}\n`)
 
-    core.setOutput('old-version', `${config.v}${currentVersion}`)
+    if (currentVersion !== undefined) {
+        core.setOutput('old-version', `${config.v}${currentVersion}`)
+    }
+
     core.setOutput('version', newTag)
     core.setOutput('release-notes', releaseNotes)
 }

version.js

@@ -1,9 +1,37 @@
+const core = require('@actions/core')
 const github = require('@actions/github')
 const semver = require('semver')
 
+const httpNotFound = 404
+
+// Returns true if the current commit already has the given tag.
+async function isAlreadyTagged(tag, config) {
+    try {
+        await config.octokit.git.getRef({
+            ...github.context.repo,
+            ref: `tags/${tag}`,
+        })
+        return true
+    } catch (error) {
+        if (error.status === httpNotFound) {
+            return false
+        }
+
+        throw error
+    }
+}
+
 // Tags the specified version and annotates it with the provided release notes.
-async function createRelease(version, releaseNotes, config) {
+// If idempotent is true and the commit already contains the tag, the commit
+// is untouched.
+async function createRelease(version, releaseNotes, config, idempotent) {
     const tag = `${config.v}${version}`
+
+    if (idempotent && await isAlreadyTagged(tag, config)) {
+        core.info(`Commit is already tagged with ${tag} -- skipping`)
+        return tag
+    }
+
     const tagCreateResponse = await config.octokit.git.createTag({
         ...github.context.repo,
         tag: tag,