Can you provide steps to integrate Hetzner Cloud with Google Cloud Functions in TypeScript

Question

Pulumi · Accepted Answer

Integrating Hetzner Cloud with Google Cloud Functions involves a few steps. You need to have a mechanism to trigger Google Cloud Functions based on some criteria or actions occurring within Hetzner Cloud. Because there isn’t a direct plugin or integration between Hetzner Cloud and Google Cloud Functions, you will typically use an intermediary, such as Google Pub/Sub or an HTTP webhook that your Cloud Function can listen to.

Here are the steps to set up a Google Cloud Function that can be triggered by actions in Hetzner Cloud:

1. **Set up Google Cloud Functions**: Ensure you have a Google Cloud account and a project where you can deploy Cloud Functions.
2. **Write the Google Cloud Function**: Write the functionality you want to run upon triggering inside this function. This might include actions like responding to server events from Hetzner or processing data that you send from Hetzner to Google Cloud.
3. **Create a trigger mechanism**: Determine how you will trigger your Cloud Function. This can be through an HTTP request or a Pub/Sub topic.
4. **Configure Hetzner Cloud to trigger the function**: Depending on what events you want to respond to, configure your Hetzner Cloud to make HTTP requests to the Cloud Function's endpoint, or, if using Pub/Sub, publish messages to the topic that your Cloud Function subscribes to.

Let's walk through setting up a simple Google Cloud Function that will log a greeting message. We'll assume that it would be triggered by an HTTP request which could be sent programmatically from Hetzner Cloud for the sake of an example.

```typescript
import * as gcp from '@pulumi/gcp';

// Create a Google Cloud Function to be triggered
const greetingFunction = new gcp.cloudfunctions.Function("greetingFunction", {
    // name: If omitted, Pulumi will autoname the function
    runtime: "nodejs10",               // Specify the runtime language
    availableMemoryMb: 128,            // Allocate memory
    sourceArchiveBucket: 'source-bucket', // Specify the bucket with function source
    sourceArchiveObject: 'source-file.zip', // Specify the ZIP archive with index.js or index.ts at root
    entryPoint: 'helloWorld',          // Function within the code to call when triggered
    triggerHttp: true,                 // We will use an HTTP trigger
    region: 'us-central1'              // Deploy function in the desired region
});

// Export the HTTPS trigger URL so that we can easily access it
export const url = greetingFunction.httpsTriggerUrl;

// Inside your ‘index.js’ or ‘index.ts’ file, you'd define the function like this:
/* 
exports.helloWorld = (req, res) => {
    console.log("Greeting from Pulumi!");
    res.status(200).send('Hello World!');
};
*/
```

In this script, replace `'source-bucket'` and `'source-file.zip'` with your actual Google Cloud Storage bucket and the file containing your function code respectively. The function code in `index.js` should be packed into a `.zip` file and uploaded to the specified bucket.

In this example, we chose an HTTP trigger for the Google Cloud Function, making it possible to trigger it via HTTP requests from any service, including Hetzner Cloud.

Now let's imagine that you have a scenario on Hetzner Cloud where, upon a certain event (like deploying a new server), you need to call this function. You can make an HTTP request to the `url` exported by the script above from your server within Hetzner Cloud.

Remember that if you choose to use Pub/Sub as a method of triggering, you would need to set up a Pub/Sub topic and then modify the Cloud Function to be triggered by messages on that topic.

Remember to secure your function — when you are using HTTP triggers, make sure you authenticate your requests and don't expose sensitive operations to the public internet. You can achieve this using Google Cloud IAM roles and by setting up proper authentication on the function.

Always refer to the official Google Cloud Function [documentation](https://cloud.google.com/functions/docs) when configuring and deploying Cloud Functions to ensure that you are following the best practices and using the latest features.