Add a function to trigger a GitHub workflow

The GitHub workflow must have a `workflow_dispatch` trigger for this to
work. The `workflow_id` is the file name of the workflow, e.g.
`sync-ref.yml`.

This function is a slightly edited version of a function that has been
in use in https://github.com/git-for-windows/gfw-helper-github-app for
quite a while. But the test is new.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

GitGitGadget/github-api-request.js

@@ -0,0 +1,11 @@
+const gitHubAPIRequest = async (context, token, method, requestPath, payload) => {
+    const { httpsRequest } = require('./https-request')
+    const headers = token ? { Authorization: `Bearer ${token}` } : null
+    const answer = await httpsRequest(context, null, method, requestPath, payload, headers)
+    if (answer.error) throw answer.error
+    return answer
+}
+
+module.exports = {
+    gitHubAPIRequest
+}

GitGitGadget/trigger-workflow-dispatch.js

@@ -0,0 +1,54 @@
+const { gitHubAPIRequest } = require('./github-api-request')
+const { gitHubAPIRequestAsApp } = require('./github-api-request-as-app')
+
+const sleep = async (milliseconds) => {
+    return new Promise((resolve) => {
+        setTimeout(resolve, milliseconds)
+    })
+}
+
+const getActorForToken = async (context, token) => {
+    try {
+        const { login } = await gitHubAPIRequest(context, token, 'GET', '/user')
+        return login
+    } catch (e) {
+        if (e.statusCode !== 403 || e.json?.message !== 'Resource not accessible by integration') throw e
+        const answer = await gitHubAPIRequestAsApp(context, 'GET', '/app')
+        return `${answer.slug}[bot]`
+    }
+}
+
+const waitForWorkflowRun = async (context, token, owner, repo, workflow_id, after, actor) => {
+    if (!actor) actor = await getActorForToken(context, token)
+    let counter = 0
+    for (;;) {
+        const res = await gitHubAPIRequest(
+            context,
+            token,
+            'GET',
+            `/repos/${owner}/${repo}/actions/runs?actor=${actor}&event=workflow_dispatch&created=>${after}`
+        )
+        const filtered = res.workflow_runs.filter(e => e.path === `.github/workflows/${workflow_id}`)
+        if (filtered.length > 0) return filtered
+        if (counter++ > 30) throw new Error(`Times out waiting for workflow?`)
+        await sleep(1000)
+    }
+}
+
+const triggerWorkflowDispatch = async (context, token, owner, repo, workflow_id, ref, inputs) => {
+    const { headers: { date } } = await gitHubAPIRequest(
+        context,
+        token,
+        'POST',
+        `/repos/${owner}/${repo}/actions/workflows/${workflow_id}/dispatches`,
+        { ref, inputs }
+    )
+
+    const runs = await waitForWorkflowRun(context, token, owner, repo, workflow_id, new Date(date).toISOString())
+    return runs[0]
+}
+
+module.exports = {
+    triggerWorkflowDispatch,
+    waitForWorkflowRun
+}

__tests__/trigger-workflow-dispatch.test.js

@@ -0,0 +1,47 @@
+const mockHTTPSRequest = jest.fn(async (_context, _hostname, method, requestPath) => {
+    if (method === 'POST' && requestPath === '/repos/hello/world/actions/workflows/the-workflow.yml/dispatches') {
+        return {
+            headers: {
+                date: '2023-01-23T01:23:45Z'
+            }
+        }
+    }
+    if (method === 'GET' && requestPath === '/user') return { login: 'the actor' }
+    if (method === 'GET' && requestPath === '/repos/hello/world/actions/runs?actor=the actor&event=workflow_dispatch&created=>2023-01-23T01:23:45.000Z') {
+        return {
+            workflow_runs: [
+                { path: 'not this one.yml' },
+                { path: '.github/workflows/the-workflow.yml', breadcrumb: true },
+                { path: 'neither this one.yml' }
+            ]
+        }
+    }
+    throw new Error(`Unexpected requestPath: ${method} '${requestPath}'`)
+})
+jest.mock('../GitGitGadget/https-request', () => { return { httpsRequest: mockHTTPSRequest } })
+
+const { triggerWorkflowDispatch } = require('../GitGitGadget/trigger-workflow-dispatch')
+
+const { generateKeyPairSync } = require('crypto')
+
+const { privateKey } = generateKeyPairSync('rsa', {
+    modulusLength: 2048,
+    publicKeyEncoding: {
+        type: 'spki',
+        format: 'pem'
+    },
+    privateKeyEncoding: {
+        type: 'pkcs8',
+        format: 'pem',
+    }
+})
+process.env['GITHUB_APP_PRIVATE_KEY'] = privateKey
+
+test('trigger a workflow_dispatch event and wait for workflow run', async () => {
+    const context = {}
+    const run = await triggerWorkflowDispatch(context, 'my-token', 'hello', 'world', 'the-workflow.yml', 'HEAD', { abc: 123 })
+    expect(run).toEqual({
+        path: '.github/workflows/the-workflow.yml',
+        breadcrumb: true
+    })
+})