Reusable Component to Create Globally-distributed Applications with Azure Cosmos DB

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This example demonstrates the usage of Pulumi to create globally-distributed applications with Azure Cosmos DB as the backend and pluggable infrastrustructure as the web tier.

The application shows several notable features:

1. Easy global deployments - a config setting provides a list of all the regions to deploy and a single execution deploys across them all.
2. Abstraction - the CosmosApp component - abstracts away all the common logic for a global app with Cosmos DB multi-region data distribution and Traffic Manager for routing the traffic.
3. Multi-model - examples are provided for serverless functions, containers, and virtual machines, all fitting to the above abstraction.

CosmosApp component

The CosmosApp defines a skeleton for the application. While not limiting the type of compute resources, it creates the multi-regional pieces of the infrastructure:

The application has three example of using this component with the following compute services:

• Azure Functions
• Azure Container Instances
• Azure VM Scale Sets + Azure Load Balancer

Prerequisites

1. Install Pulumi
2. Configure Azure credentials

Steps

Step 1: Create a new stack

$ pulumi stack init dev

Step 2: Log in to the Azure CLI

You will be prompted to do this during deployment if you forget this step.

$ az login

Step 3: Install NPM dependencies

$ npm install

Step 4: Deploy your changes

Run pulumi up to preview and deploy changes:

$ pulumi up
Previewing changes:
+  azure-ts-cosmosapp-component-dev  create
+  examples:azure:CosmosApp vms create
+  azure:network:VirtualNetwork vnet-westeurope create
+  azure:network:PublicIp pip-westeurope create
+  azure:trafficmanager:Profile tmvms create
+  azure:trafficmanager:Endpoint tmvmswesteurope create
+  azure:cosmosdb:Account cosmos-vms
...

Step 5: Check the deployed website endpoints

Three endpoints are now available. For example,

$ pulumi stack output functionsEndpoint
http://functionscosmosfunc-rgcc15ea50.trafficmanager.net/api/cosmos

$ curl "$(pulumi stack output functionsEndpoint)"
Document 'cosmos' not found

Go to the Azure portal and add a document with the ID “cosmos” to receive a non-empty response.

Running Unit Tests

The unittests.ts file contains two sample unit tests that can be run with Mocha:

mocha -r ts-node/register unittests.ts

Running Policy Pack

The policy folder contains two sample policies that can be applied with the policy-pack argument:

pulumi up --policy-pack policy