Export all resources from Kubernetes (k8s) clusters. Resources are exported to separate folders and files by namespace and API name.

export-k8s.sh

#!/bin/bash

backup_folder="kubernetes_backup"
# Create a directory to store the backup
mkdir -p $backup_folder

# Get a list of all resource resources, including both namespaced and non-namespaced resources
resources=$(kubectl api-resources --verbs=list -o name)

# Get a list of all namespaces
namespaces=$(kubectl get namespaces -o=jsonpath='{.items[*].metadata.name}')

# Retrieve non-namespaced resources
for resource in $resources; do
    echo "$(date +"%Y-%m-%d %H:%M:%S") - Exporting: $resource"
    # Check if the resource is namespaced
    if [ $(kubectl get $resource -o jsonpath='{.items[*].metadata.namespace}' | wc -w) -gt 0 ]; then # if namespaced
        echo "$(date +"%Y-%m-%d %H:%M:%S") - Exporting (namespaced): $resource"
        for namespace in $namespaces; do
            echo "$(date +"%Y-%m-%d %H:%M:%S") - Exporting: $namespace/$resource"
            if [ $(kubectl get $resource --namespace=$namespace -o jsonpath='{.items[*].metadata.name}' | wc -w) -gt 0 ]; then
                mkdir -p $backup_folder/$namespace/$resource
                # Write each item to its own file
                for item in $(kubectl get $resource --namespace=$namespace -o jsonpath='{.items[*].metadata.name}'); do
                    echo "$(date +"%Y-%m-%d %H:%M:%S") - Exporting: $namespace/$resource/$item"
                    kubectl get $resource $item --namespace=$namespace -o yaml >$backup_folder/$namespace/$resource/$item.yaml
                done
            fi
        done
    else # if not namespaced
        echo "$(date +"%Y-%m-%d %H:%M:%S") - Exporting (non-namespaced): $resource"
        if [ $(kubectl get $resource -o jsonpath='{.items[*].metadata.name}' | wc -w) -gt 0 ]; then
            # kubectl get $resource -o yaml >$backup_folder/${resource}.yaml
            mkdir -p $backup_folder/non-namespaced/$resource
            for item in $(kubectl get $resource -o jsonpath='{.items[*].metadata.name}'); do
                echo "$(date +"%Y-%m-%d %H:%M:%S") - Exporting: $resource/$item"
                kubectl get $resource $item -o yaml >$backup_folder/non-namespaced/$resource/$item.yaml
            done
        fi
    fi
done

This worked pretty well, but if you don't have resources in the default namespace the first if on line 17 doesn't work. I had to modify this to add the -A flag to search every namespace here as I didn't have pods or deployments in the default namespace and it would end up skipping pods or deployments completely if nothing existed in the default namespace:

+    if [ $(kubectl get $resource -o jsonpath='{.items[*].metadata.namespace}' -A | wc -w) -gt 0 ]; then # if namespaced
-    if [ $(kubectl get $resource -o jsonpath='{.items[*].metadata.namespace}' | wc -w) -gt 0 ]; then # if namespaced

kubectl plugin get-resources does this

Get all resources

kubectl get-resources

Get specific namespace resources

kubectl get-resources --namespace=default --exclude-cluster-resources=true

Get multiple namespace resources

kubectl get-resources --namespace=ns1 --namespace=ns2 --namespace=ns3 ... --exclude-cluster-resources=true

Output resources to a directory

kubectl get-resources --namespace=default --exclude-cluster-resources=true --output=your_output_dir

See --help for other options

kubectl get-resources --help