added readme, go mod, go sum, and comments saying why target port will never be undefined

Author: rayaisaiah

tools/azure-npm-to-cilium-validator/README.md

@@ -0,0 +1,46 @@
+# Azure NPM to Cilium Validator
+
+This tool validates the migration from Azure NPM to Cilium.
+
+## Prerequisites
+
+- Go 1.16 or later
+- A Kubernetes cluster with Azure NPM installed
+
+## Installation
+
+Clone the repository and navigate to the tool directory:
+
+```bash
+git clone https://github.com/Azure/azure-container-networking.git
+cd azure-container-networking/tools/azure-npm-to-cilium-validator
+```
+
+## Setting Up Dependencies
+
+Initialize the Go module and download dependencies:
+
+```bash
+go mod tidy
+go mod vendor
+```
+
+## Running the Tool
+
+Run the following command with the path to your kube config file with the cluster you want to validate.
+
+```bash
+go run azure-npm-to-cilium-validator.go --kubeconfig ~/.kube/config
+```
+
+This will execute the validator and print the migration summary.
+
+## Running Tests
+
+To run the tests for the Azure NPM to Cilium Validator, use the following command in the azure-npm-to-cilium-validator directory:
+
+```bash
+go test .
+```
+
+This will execute all the test files in the directory and provide a summary of the test results.

tools/azure-npm-to-cilium-validator/azure-npm-to-cilium-validator.go

@@ -317,6 +317,8 @@ func checkServiceTargetPortMatchPolicyPorts(servicePorts []corev1.ServicePort, p
 			if int(policyPort.Port.IntVal) == 0 {
 				return false
 			}
+			// Check if the service target port and protocol matches the policy port and protocol
+			// Note that the service target port will never been undefined as it defaults to port which is a required field when Ports is defined
 			if servicePort.TargetPort.IntValue() == int(policyPort.Port.IntVal) && string(servicePort.Protocol) == string(*policyPort.Protocol) {
 				matchedserviceTargetPortToPolicyPort = true
 				break

tools/azure-npm-to-cilium-validator/azure-npm-to-cilium-validator_test.go

@@ -1567,6 +1567,7 @@ func TestGetExternalTrafficPolicyClusterServices(t *testing.T) {
 		},
 		// add ut where target port is nil
 		// add a ut where target port matches to portocol
+		// add a ut where the port is 0
 
 		// Scenarios where there are LoadBalancer or NodePort services with externalTrafficPolicy=Cluster and there are multiple policies
 

tools/azure-npm-to-cilium-validator/go.mod

@@ -0,0 +1,9 @@
+module azure-npm-to-cilium-validator
+
+go 1.16
+
+require (
+	k8s.io/api v0.23.0
+	k8s.io/apimachinery v0.23.0
+	k8s.io/client-go v0.23.0
+)