Fix event.json not being copied to /github/workflow in kubernetes-novolume mode (#287)

In run-script-step, the _temp directory was being copied to the workflow pod,
but the _github_home and _github_workflow directories were not being moved
from their temporary location to the /github directory structure where they
are expected by GitHub Actions.

This caused event.json to be missing at /github/workflow/event.json, breaking
actions that depend on GITHUB_EVENT_PATH.

The fix adds a setup step that copies _github_home and _github_workflow from
/__w/_temp/ to /github/ after copying the temp directory to the pod, matching
the behavior of run-container-step and prepareJobScript.

Uses cp -r instead of symlinks to avoid symlink validation errors when copying
files back from the pod to the runner.

packages/k8s/src/hooks/run-script-step.ts

@@ -6,6 +6,7 @@ import { execCpFromPod, execCpToPod, execPodStep } from '../k8s'
 import { writeRunScript, sleep, listDirAllCommand } from '../k8s/utils'
 import { JOB_CONTAINER_NAME } from './constants'
 import { dirname } from 'path'
+import * as shlex from 'shlex'
 
 export async function runScriptStep(
   args: RunScriptStepArgs,
@@ -26,6 +27,23 @@ export async function runScriptStep(
   const runnerTemp = `${workdir}/_temp`
   await execCpToPod(state.jobPod, runnerTemp, containerTemp)
 
+  // Copy GitHub directories from temp to /github
+  const setupCommands = [
+    'mkdir -p /github',
+    'cp -r /__w/_temp/_github_home /github/home',
+    'cp -r /__w/_temp/_github_workflow /github/workflow'
+  ]
+
+  try {
+    await execPodStep(
+      ['sh', '-c', shlex.quote(setupCommands.join(' && '))],
+      state.jobPod,
+      JOB_CONTAINER_NAME
+    )
+  } catch (err) {
+    core.debug(`Failed to copy GitHub directories: ${JSON.stringify(err)}`)
+  }
+
   // Execute the entrypoint script
   args.entryPoint = 'sh'
   args.entryPointArgs = ['-e', containerPath]

packages/k8s/src/k8s/index.ts

@@ -96,20 +96,30 @@ export async function createJobPod(
   appPod.spec.securityContext = {
     fsGroup: 1001
   }
+
+  // Extract working directory from GITHUB_WORKSPACE
+  // GITHUB_WORKSPACE is like /__w/repo-name/repo-name
+  const githubWorkspace = process.env.GITHUB_WORKSPACE
+  const workingDirPath = githubWorkspace?.split('/').slice(-2).join('/') ?? ''
+
+  const initCommands = [
+    'mkdir -p /mnt/externals',
+    'mkdir -p /mnt/work',
+    'mkdir -p /mnt/github',
+    'mv /home/runner/externals/* /mnt/externals/'
+  ]
+
+  if (workingDirPath) {
+    initCommands.push(`mkdir -p /mnt/work/${workingDirPath}`)
+  }
+
   appPod.spec.initContainers = [
     {
       name: 'fs-init',
       image:
         process.env.ACTIONS_RUNNER_IMAGE ||
         'ghcr.io/actions/actions-runner:latest',
-      command: [
-        'sh',
-        '-c',
-        `mkdir -p /mnt/externals && \\
-         mkdir -p /mnt/work && \\
-         mkdir -p /mnt/github && \\
-         mv /home/runner/externals/* /mnt/externals/`
-      ],
+      command: ['sh', '-c', initCommands.join(' && ')],
       securityContext: {
         runAsGroup: 1001,
         runAsUser: 1001