refactor: isolate client library

Author: integrii

.github/workflows/build.yml

@@ -0,0 +1,13 @@
+name: Build example container
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Build Docker image
+        run: docker build -t kuberhealthy-js-check .

.github/workflows/publish.yml

@@ -0,0 +1,22 @@
+name: Publish package
+
+on:
+  release:
+    types: [published]
+
+jobs:
+  publish:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-node@v3
+        with:
+          node-version: 18
+          registry-url: https://npm.pkg.github.com
+      - run: npm publish
+        working-directory: client
+        env:
+          NODE_AUTH_TOKEN: ${{ secrets.GITHUB_TOKEN }}

Dockerfile

@@ -1,6 +1,7 @@
 FROM node:20-alpine
 WORKDIR /app
 COPY package.json ./
+COPY client ./client
 RUN npm install --production
 COPY check.js ./
 CMD ["node", "check.js"]

README.md

@@ -1,10 +1,34 @@
 # JavaScript Kuberhealthy Client
 
-This directory contains an example external check for [Kuberhealthy](https://github.com/kuberhealthy/kuberhealthy) written in JavaScript. The script demonstrates how to report a successful run or a failure back to Kuberhealthy using environment variables provided to every checker pod.
+This repository contains a small client library and example external check for [Kuberhealthy](https://github.com/kuberhealthy/kuberhealthy).
 
-## Usage
+The reusable client lives in the `client/` directory and is published as `@kuberhealthy/client`. It can be imported into your own Node.js applications to report check results back to Kuberhealthy. An example checker using the client is provided in `check.js`.
 
-1. **Add your logic**: edit `check.js` and replace the placeholder section in `main` with your own check logic. Call `report(true, [])` when the check succeeds or `report(false, ["message"])` on failure.
+## Client Library
+
+The package is published to the GitHub Packages npm registry under `@kuberhealthy/client`.
+
+Install it by configuring npm to use the GitHub Packages registry for the `@kuberhealthy` scope:
+
+```bash
+echo "@kuberhealthy:registry=https://npm.pkg.github.com" >> ~/.npmrc
+npm install @kuberhealthy/client
+```
+
+Use the client in your code:
+
+```javascript
+const { KuberhealthyClient } = require('@kuberhealthy/client');
+
+const client = new KuberhealthyClient(process.env.KH_REPORTING_URL, process.env.KH_RUN_UUID);
+await client.report(true, []);
+```
+
+Node.js 18 or newer is required for the built in `fetch` API used by the client.
+
+## Example Checker
+
+1. **Add your logic**: edit `check.js` and replace the placeholder section in `main` with your own check logic. Call `client.report(true, [])` when the check succeeds or `client.report(false, ["message"])` on failure.
 2. **Build the image**: run `make build IMAGE=my-registry/my-check:tag` to build a container image containing your check.
 3. **Push the image**: `make push IMAGE=my-registry/my-check:tag`.
 4. **Create a KuberhealthyCheck**: write a khcheck resource that references your image and apply it to clusters where Kuberhealthy runs.
@@ -14,7 +38,7 @@ The check relies on two environment variables set automatically by Kuberhealthy:
 - `KH_REPORTING_URL` – the endpoint where status reports are posted.
 - `KH_RUN_UUID` – the UUID for this check run. It must be sent back in the `kh-run-uuid` header.
 
-## Example khcheck
+### Example khcheck
 
 ```yaml
 apiVersion: kuberhealthy.github.io/v2

check.js

@@ -1,3 +1,5 @@
+const { KuberhealthyClient } = require('@kuberhealthy/client');
+
 const reportingURL = process.env.KH_REPORTING_URL;
 const runUUID = process.env.KH_RUN_UUID;
 
@@ -6,34 +8,17 @@ if (!reportingURL || !runUUID) {
   process.exit(1);
 }
 
-// report sends a result to Kuberhealthy
-async function report(ok, errors) {
-  const res = await fetch(reportingURL, {
-    method: 'POST',
-    headers: {
-      'Content-Type': 'application/json',
-      'kh-run-uuid': runUUID,
-    },
-    body: JSON.stringify({ ok, errors }),
-  });
-
-  if (res.ok) {
-    return;
-  }
-
-  const text = await res.text();
-  throw new Error(`Kuberhealthy responded with ${res.status}: ${text}`);
-}
+const client = new KuberhealthyClient(reportingURL, runUUID);
 
 async function main() {
   try {
     // Add your check logic here.
-    await report(true, []);
+    await client.report(true, []);
     console.log('Reported success to Kuberhealthy');
   } catch (err) {
     console.error('Check logic failed:', err);
     try {
-      await report(false, [err.message]);
+      await client.report(false, [err.message]);
     } catch (e) {
       console.error('Failed to report failure:', e);
     }
@@ -42,5 +27,3 @@ async function main() {
 }
 
 main();
-
-module.exports = { report };

client/index.js

@@ -0,0 +1,27 @@
+class KuberhealthyClient {
+  constructor(reportingURL, runUUID) {
+    if (!reportingURL || !runUUID) {
+      throw new Error('reportingURL and runUUID are required');
+    }
+    this.reportingURL = reportingURL;
+    this.runUUID = runUUID;
+  }
+
+  async report(ok, errors) {
+    const res = await fetch(this.reportingURL, {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/json',
+        'kh-run-uuid': this.runUUID,
+      },
+      body: JSON.stringify({ ok, errors }),
+    });
+
+    if (!res.ok) {
+      const text = await res.text();
+      throw new Error(`Kuberhealthy responded with ${res.status}: ${text}`);
+    }
+  }
+}
+
+module.exports = { KuberhealthyClient };

client/package.json

@@ -0,0 +1,13 @@
+{
+  "name": "@kuberhealthy/client",
+  "version": "0.1.0",
+  "description": "Node.js client for Kuberhealthy",
+  "main": "index.js",
+  "files": ["index.js"],
+  "publishConfig": {
+    "registry": "https://npm.pkg.github.com"
+  },
+  "engines": {
+    "node": ">=18"
+  }
+}

package.json

@@ -1,10 +1,16 @@
 {
-  "name": "kuberhealthy-javascript-client",
+  "name": "kuberhealthy-check-example",
   "version": "0.1.0",
-  "description": "Example Kuberhealthy external check written in JavaScript",
+  "private": true,
+  "description": "Example external check for Kuberhealthy using the JavaScript client",
   "main": "check.js",
   "scripts": {
     "start": "node check.js"
   },
-  "dependencies": {}
+  "engines": {
+    "node": ">=18"
+  },
+  "dependencies": {
+    "@kuberhealthy/client": "file:./client"
+  }
 }