What is the process of incorporating Nomad with Google Cloud Functions in TypeScript

Question

Pulumi · Accepted Answer

Incorporating HashiCorp Nomad with Google Cloud Functions involves creating the Google Cloud Function resources and configuring Nomad to interact with these resources. Pulumi allows you to define and manage infrastructure as code using familiar programming languages such as TypeScript.

Firstly, we'll need to declare the Google Cloud Function using Pulumi's GCP provider. Then, we will illustrate how you can configure a basic Nomad job file that could trigger or interact with this Google Cloud Function. Note that Nomad itself would typically run on a set of dedicated servers or inside a cloud service like Google Compute Engine, and it would communicate with Google Cloud Functions via the functions' HTTP triggers or other event triggers.

Here is a step-by-step guide, including a Pulumi program in TypeScript, which creates a new Google Cloud Function:

1. **Define the Google Cloud Function Resource**: Using Pulumi's GCP (Google Cloud) provider, we can define a new Cloud Function resource. This resource represents the Google Cloud Function we are deploying.

2. **Nomad Configuration**: Although Pulumi does not directly interface with Nomad's configuration files (`*.nomad`), you can still write a Nomad job configuration that specifies tasks to invoke or otherwise interact with the Google Cloud Function.

3. **Function Execution & Testing**: Once your function and Nomad cluster are set up, you can trigger the function in various ways, such as by HTTP requests if you're using an HTTP trigger or by other Google Cloud events if you've set up an EventTrigger.

Below is a TypeScript program using Pulumi for setting up a Google Cloud Function:

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

// Define the Google Cloud Function
const myFunction = new gcp.cloudfunctions.Function("myFunction", {
    runtime: "nodejs10",  // The runtime for the function.
    availableMemoryMb: 128,
    sourceArchiveBucket: "my-bucket", // The GCS bucket containing the zip archive which contains the function's source code.
    sourceArchiveObject: "path/to/source.zip", // The GCS object containing the source.
    triggerHttp: true, // We're using an HTTP trigger for simplicity.
    entryPoint: "myFunction", // The name of the function (as defined in JavaScript).
});

// Export the function's URL for easy access.
// You might use this URL in your Nomad job configuration.
export const functionUrl = myFunction.httpsTriggerUrl;

// Note: We're not showing the creation of the GCS bucket or object in this program.
// You would need to upload your function code to GCS before deploying this Pulumi program.
```

The above Pulumi program sets up a simple Google Cloud Function, but we don't incorporate interaction with Nomad directly within this code as it's beyond the scope of Pulumi's current capabilities. To work with Nomad, you will need to set up Nomad servers and client nodes separately and then use Nomad's job specification files to define tasks that should run—these might invoke your Cloud Function using HTTP requests or in response to specific triggers.

Here is an example of how a Nomad job configuration might look like for an HTTP-triggered function:

```hcl
# myfunction.nomad
job "invoke-function" {
  datacenters = ["dc1"]

group "group1" {
    task "invoke" {
      driver = "exec"

config {
        command = "curl"
        args    = ["${FUNCTION_URL}"] // You would pass your function URL here.
      }
    }
  }
}
```

This `.nomad` file would be run by the Nomad command-line tool, not Pulumi. The `${FUNCTION_URL}` variable would be replaced with the actual URL of your deployed Cloud Function (e.g., `httpsTriggerUrl` exported by the Pulumi program).

Before you can create this infrastructure, you need to set up and authenticate your Pulumi CLI with Google Cloud. Ensure that your GCP credentials are configured correctly, and then you can run `pulumi up` to deploy the infrastructure as defined in the TypeScript program above.

Remember, this is only one part of the setup. The complete process would consist of:
- Setting up your Nomad cluster on GCP using services like Compute Engine.
- Defining and running Nomad job files that interact with your cloud resources.

Each of these tasks can be defined as code—whether that be Pulumi code, HCL for Nomad configuration, or another tooling that you use in your infrastructure management practices.