Refactor step into standalone action

.github/workflows/terraform.yaml

@@ -51,62 +51,12 @@ jobs:
       - run: terraform show -no-color tfplan > summary.txt
 
       - name: Create status check with details
-        uses: actions/github-script@v7
+        uses: ./actions/checks
         with:
-          github-token: ${{ github.token }}
-          script: |
-            const fs = require('fs').promises
-            const plan = JSON.parse(await fs.readFile('tfplan.json', 'utf-8'))
-            const humanSummary = await fs.readFile('summary.txt', 'utf-8')
-            let applyLog;
-            try {
-              applyLog = await fs.readFile('apply.log', 'utf-8')
-            } catch {}
-
-            function countActions(plan, type) {
-              return plan.resource_changes.filter(ch => ch.change.actions.includes(type)).length
-            }
-            const createCount = countActions(plan, 'create')
-            const updateCount = countActions(plan, 'update')
-            const deleteCount = countActions(plan, 'delete')
-
-            const noChanges = createCount == 0 && updateCount == 0 && deleteCount == 0
-            const title = noChanges
-              ? "No changes"
-              : (context.eventName === 'push'
-                ? `${createCount} added, ${updateCount} changed, ${deleteCount} destroyed`
-                : `${createCount} to add, ${updateCount} to change, ${deleteCount} to destroy`
-              )
-
-            const codefence = "```"
-            const summary = `
-            # Terraform Plan
-            ${codefence}
-            ${humanSummary.trim("\n")}
-            ${codefence}
-            ${!!applyLog ? `
-            # Terraform Apply
-            ${codefence}
-            ${applyLog.replace(/\u001b\[[^m]+m/g, '').trim()}
-            ${codefence}
-            ` : ""}
-            `
-
-            const sha = context.eventName === 'pull_request'
-              ? context.payload.pull_request.head.sha
-              : context.sha
-            await github.rest.checks.create({
-              owner: context.repo.owner,
-              repo: context.repo.repo,
-              head_sha: sha,
-              status: 'completed',
-              conclusion: noChanges ? 'neutral' : 'success',
-              name: context.eventName === 'push' ? "Apply" : "Plan",
-              output: {
-                title,
-                summary,
-              },
-            });
+          token: ${{ github.token }}
+          plan-json: tfplan.json
+          plan-summary: summary.txt
+          apply-summary: apply.log
 
       - name: Show plan on PR
         uses: actions/github-script@v7

actions/checks/action.yaml

@@ -0,0 +1,17 @@
+name: "Terraform Checks"
+description: "Annotate a commit with details about the Terraform run"
+inputs:
+  token:
+    description: "GitHub token"
+    required: true
+  plan-json:
+    description: "JSON file containing the plan"
+    required: true
+  plan-summary:
+    description: "Log file with the human readable plan summary"
+    required: true
+  apply-summary:
+    description: "Log file with the human readable apply summary"
+runs:
+  using: "node20"
+  main: "index.js"

actions/checks/index.js

@@ -0,0 +1,75 @@
+const core = require("@actions/core");
+const github = require("@actions/github");
+const fs = require("fs").promises;
+
+const planJson = core.getInput("plan-json");
+const planSummary = core.getInput("plan-summary");
+const applySummary = core.getInput("apply-summary");
+const ghToken = core.getInput("token");
+const oktokit = github.getOctokit(ghToken);
+
+async function createCheck() {
+  const { context } = github;
+
+  const plan = JSON.parse(await fs.readFile(planJson, "utf-8"));
+  const humanSummary = await fs.readFile(planSummary, "utf-8");
+  let applyLog;
+  if (applySummary) {
+    try {
+      applyLog = await fs.readFile(applySummary, "utf-8");
+    } catch {}
+  }
+
+  function countActions(plan, type) {
+    return plan.resource_changes.filter((ch) =>
+      ch.change.actions.includes(type)
+    ).length;
+  }
+  const createCount = countActions(plan, "create");
+  const updateCount = countActions(plan, "update");
+  const deleteCount = countActions(plan, "delete");
+
+  const noChanges = createCount == 0 && updateCount == 0 && deleteCount == 0;
+  const title = noChanges
+    ? "No changes"
+    : context.eventName === "push"
+    ? `${createCount} added, ${updateCount} changed, ${deleteCount} destroyed`
+    : `${createCount} to add, ${updateCount} to change, ${deleteCount} to destroy`;
+
+  const codefence = "```";
+  const summary = `
+# Terraform Plan
+${codefence}
+${humanSummary.trim()}
+${codefence}
+${
+  !!applyLog
+    ? `
+# Terraform Apply
+${codefence}
+${applyLog.replace(/\u001b\[[^m]+m/g, "").trim()}
+${codefence}
+`
+    : ""
+}
+`;
+
+  const sha =
+    context.eventName === "pull_request"
+      ? context.payload.pull_request?.head.sha
+      : context.sha;
+  await oktokit.rest.checks.create({
+    owner: context.repo.owner,
+    repo: context.repo.repo,
+    head_sha: sha,
+    status: "completed",
+    conclusion: noChanges ? "neutral" : "success",
+    name: context.eventName === "push" ? "Apply" : "Plan",
+    output: {
+      title,
+      summary,
+    },
+  });
+}
+
+createCheck();