Deploying GitLab on Azure Kubernetes Service

Q: Deploy the gitlab-service helm chart on Azure Kubernetes Service (AKS)

Deploy the gitlab-service helm chart on Azure Kubernetes Service (AKS)

To deploy the gitlab-service helm chart on Azure Kubernetes Service (AKS), we'll perform a few distinct steps:

Create an AKS cluster: This involves defining the AKS cluster resource and its dependent resources in the Pulumi program.
Install the Helm Chart: Once the AKS cluster is up and running, we'll deploy the gitlab-service Helm chart into our AKS cluster using Pulumi's Helm Chart resource.

For this task, we will use the azure-native and kubernetes Pulumi providers. The azure-native provider allows us to provision resources in Azure using Pulumi, whereas the kubernetes provider allows us to interact with Kubernetes resources, including deploying Helm charts.

Below is a Pulumi program written in TypeScript that will set up an AKS cluster and deploy the gitlab-service helm chart into it. I have included comments within the code to help explain each section and the resources being created:

import * as pulumi from "@pulumi/pulumi";
import * as azure_native from "@pulumi/azure-native";
import * as k8s from "@pulumi/kubernetes";

// Step 1: Create an AKS cluster
// We begin by creating a Resource Group. AKS cluster and other resources will live in this group.
const resourceGroup = new azure_native.resources.ResourceGroup("myResourceGroup");

// Define the AKS cluster resource. Here we assume default settings but in a real world scenario, you would customize them according to your needs.
const aksCluster = new azure_native.containerservice.ManagedCluster("myAksCluster", {
    resourceGroupName: resourceGroup.name,
    kubernetesVersion: "1.20.7", // Define the version of Kubernetes you want to use
    // Define the properties of the cluster such as the size and count of worker nodes.
    agentPoolProfiles: [{
        count: 2,
        vmSize: azure_native.containerservice.ContainerServiceVMSizeTypes.Standard_DS2_v2,
        mode: "System",
        name: "agentpool",
    }],
    // You can specify additional features like Azure AD integration, network configuration, RBAC, etc. For simplicity, we use only the necessary configs.
    dnsPrefix: "myakscluster-dns",
    identity: {
        type: azure_native.containerservice.ResourceIdentityType.SystemAssigned,
    },
});

// Expose the AKS cluster details required for connecting to the cluster once it is created
export const kubeconfig = aksCluster.kubeConfigRaw;

// Step 2: Deploy the Helm chart
// To interact with our AKS cluster, we instantiate a provider.
const aksK8sProvider = new k8s.Provider("aksK8sProvider", {
    kubeconfig: kubeconfig,
});

// Now, we deploy the gitlab-service Helm chart using the Kubernetes provider pointing to our AKS cluster.
const gitlabServiceChart = new k8s.helm.v3.Chart("gitlab-service", {
    chart: "gitlab",
    version: "5.0.0", // Specify the version of the chart you want to install
    namespace: "default", // Define the namespace where the Helm chart will be installed
    fetchOpts: { 
        repo: "https://charts.gitlab.io/", // The Helm repository where the gitlab chart is stored
    },
}, {
    provider: aksK8sProvider,
});

// Important: you will need to clarify any additional configurations for gitlab-service Helm chart, here we are using only the default values.
// In a production setup, you'd need to provide a custom `values.yaml` or a set of overridden values for tuning the configuration of GitLab.

// Export the public endpoint of GitLab. Assume GitLab's Service is of LoadBalancer type and you want external access (this may vary based on actual Helm chart configuration).
export const gitlabServiceEndpoint = gitlabServiceChart.getResourceProperty("v1/Service", "gitlab-gitlab-service", "status").apply(status => status.loadBalancer.ingress[0].ip);

Here's what the program does:

Resource Group: We create an Azure resource group to house our AKS cluster.
AKS Cluster: We create an AKS cluster (ManagedCluster) with a specified Kubernetes version and a simple agent pool profile, which controls the VM size and node count.
Kubeconfig: We export the kubeconfig output to allow access to the Kubernetes cluster.
Kubernetes Provider: We set up a Pulumi Kubernetes provider to interact with our AKS cluster.
Helm Chart Deployment: We deploy the GitLab Helm chart to the default namespace in our AKS cluster using the Kubernetes provider. The fetchOpts property specifies the Helm chart's repository URL.

To use the above program:

Make sure you have Pulumi installed and configured with Azure credentials.
Save the code to a file named index.ts.
Run pulumi up to execute the Pulumi program and create the resources.

After running the program, Pulumi will output the connection details for the AKS cluster and the IP endpoint for the gitlab-service, which can be used to access the GitLab instance once the Helm chart is deployed and the service is up.