Splunk Operator for Kubernetes

The Splunk Operator for Kubernetes (SOK) makes it easy for Splunk Administrators to deploy and operate Enterprise deployments in a Kubernetes infrastructure. Packaged as a container, it uses the operator pattern to manage Splunk-specific custom resources, following best practices to manage all the underlying Kubernetes objects for you.

This repository is used to build the Splunk Operator for Kubernetes (SOK). If you are just looking for documentation on how to deploy and use the latest release, please see the Getting Started Documentation.

Prerequisites

You must have Docker Engine installed to build the Splunk Operator.

This project uses Go modules, and requires golang 1.13 or later. You must export GO111MODULE=on if cloning these repositories into your $GOPATH (not recommended).

The Kubernetes Operator SDK must also be installed to build this project.

git clone -b v0.18.2 https://github.com/operator-framework/operator-sdk
cd operator-sdk
make tidy
make install

You may need to add $GOPATH/bin to you path to run the operator-sdk command line tool:

export PATH=${PATH}:${GOPATH}/bin

It is also recommended that you install the following golang tools, which are used by various make targets:

go get -u golang.org/x/lint/golint
go get -u golang.org/x/tools/cmd/cover
go get -u github.com/mattn/goveralls
go get -u github.com/mikefarah/yq/v3
go get -u github.com/go-delve/delve/cmd/dlv

Cloning this repository

git clone git@github.com:splunk/splunk-operator.git
cd splunk-operator

Repository overview

This repository consists of the following code used to build the splunk-operator binary:

cmd/manager/main.go: Provides the main() function, where everything begins
pkg/apis/: Source code for the operator's custom resource definition types
pkg/controllers/: Used to register controllers that watch for changes to custom resources
pkg/splunk/enterprise/: Source code for controllers that manage Splunk Enterprise resources
pkg/splunk/controller/: Common code shared across Splunk controllers
pkg/splunk/common/: Common code used by most other splunk packages
pkg/splunk/client/: Simple client for Splunk Enterprise REST API
pkg/splunk/test/: Common code used by other packages for unit testing

main() uses pkg/controllers to register all the enterprise controllers that manage custom resources by watching for Kubernetes events. The enterprise controllers are implemented using common code provided by the controllers package. The enterprise controllers also use the REST API client provided in the pkg/splunk/client package. The types provided by pkg/apis/ and common code in the pkg/splunk/common/ package are used universally. Note that the source code for main() is generated from a template provided by the Operator SDK.

In addition to the source code, this repository includes:

build: Build scripts, templates, etc. used to build the container image
deploy: Kubernetes YAML templates used to install the Splunk Operator
docs: Getting Started Guide and other documentation in Markdown format
test: Integration test framework built using Ginko. See docs for more info.

Building the operator

You can build the operator by just running make.

Other make targets include (more info below):

make all: builds splunk/splunk-operator container image (same as make image)
make builder: builds the splunk/splunk-operator-builder container image
make builder-image: builds splunk/splunk-operator using the splunk/splunk-operator-builder image
make builder-test: Runs unit tests using the splunk/splunk-operator-builder image
make image: builds the splunk/splunk-operator container image without using splunk/splunk-operator-builder
make local: builds the splunk-operator-local binary for test and debugging purposes
make test: Runs unit tests with Coveralls code coverage output to coverage.out
make scorecard: Runs operator-sdk scorecard tests using OLM installation bundle
make generate: runs operator-generate k8s, crds and csv commands, updating installation YAML files and OLM bundle
make package: generates tarball of the splunk/splunk-operator container image and installation YAML file
make clean: removes the binary build output and splunk/splunk-operator container image
make run: runs the splunk operator locally, monitoring the Kubernetes cluster configured in your current kubectl context
make fmt: runs go fmt on all *.go source files in this project
make lint: runs the golint utility on all *.go source files in this project

Running the Splunk Operator

Ensure that you have the Custom Resource Definitions installed in your cluster:

kubectl apply -f deploy/crds

Use this to run the operator as a local foreground process on your machine:

make run

This will use your current Kubernetes context from ~/.kube/config to manage resources in your current namespace.