Developer Setup

The Postgres-Operator is an open source project hosted on GitHub.

This guide is intended for those wanting to build the Operator from source or contribute via pull requests.

Prerequisites

The target development host for these instructions is a CentOS 7 or RHEL 7 host. Others operating systems are possible, however we do not support building or running the Operator on others at this time.

Environment Variables

The following environment variables are expected by the steps in this guide:

Variable Example Description
GOPATH $HOME/odev Golang project directory
PGOROOT $GOPATH/src/github.com/crunchydata/postgres-operator Operator repository location
PGO_BASEOS centos7 Base OS for container images
PGO_CMD kubectl Cluster management tool executable
PGO_IMAGE_PREFIX crunchydata Container image prefix
PGO_OPERATOR_NAMESPACE pgo Kubernetes namespace for the operator
PGO_VERSION 4.2.0 Operator version
examples/envs.sh contains the above variable definitions as well as others used by postgres-operator tools

Other requirements

  • The development host has been created, has access to yum updates, and has a regular user account with sudo rights to run yum.
  • GOPATH points to a directory containing src,pkg, and bin directories.
  • The development host has $GOPATH/bin added to its PATH environment variable. Development tools will be installed to this path. Defining a GOBIN environment variable other than $GOPATH/bin may yield unexpected results.
  • The development host has git installed and has cloned the postgres-operator repository to $GOPATH/src/github.com/crunchydata/postgres-operator. Makefile targets below are run from the repository directory.
  • Deploying the Operator will require deployment access to a Kubernetes cluster. Clusters built on OpenShift Container Platform (OCP) or built using kubeadm are the validation targets for Pull Requests and thus recommended for devleopment. Instructions for setting up these clusters are outside the scope of this guide.

Building

Dependencies

Configuring build dependencies is automated via the setup target in the project Makefile:

make setup

The setup target ensures the presence of:

  • GOPATH and PATH as described in the prerequisites
  • EPEL yum repository
  • golang compiler
  • dep dependency manager
  • NSQ messaging binaries
  • docker container tool
  • buildah OCI image building tool
  • expenv config tool

By default, docker is not configured to run its daemon. Refer to the docker post-installation instructions to configure it to run once or at system startup. This is not done automatically.

Compile

You will build all the Operator binaries and Docker images by running:

make all

This assumes you have Docker installed and running on your development host.

By default, the Makefile will use buildah to build the container images, to override this default to use docker to build the images, set the IMGBUILDER variable to docker

The project uses the golang dep package manager to vendor all the golang source dependencies into the vendor directory. You typically do not need to run any dep commands unless you are adding new golang package dependencies into the project outside of what is within the project for a given release.

After a full compile, you will have a pgo binary in $HOME/odev/bin and the Operator images in your local Docker registry.

Release

You can perform a release build by running:

make release

This will compile the Mac and Windows versions of pgo.

Deployment

Now that you have built the Operator images, you can push them to your Kubernetes cluster if that cluster is remote to your development host.

You would then run:

make deployoperator

To deploy the Operator on your Kubernetes cluster. If your Kubernetes cluster is not local to your development host, you will need to specify a config file that will connect you to your Kubernetes cluster. See the Kubernetes documentation for details.

Troubleshooting

Debug level logging in turned on by default when deploying the Operator.

Sample bash functions are supplied in examples/envs.sh to view the Operator logs.

You can view the Operator REST API logs with the alog bash function.

You can view the Operator core logic logs with the olog bash function.

You can view the Scheduler logs with the slog bash function.

These logs contain the following details:

Timestamp
Logging Level
Message Content
Function Information
File Information
PGO version

Additionally, you can view the Operator deployment Event logs with the elog bash function.

You can enable the pgo CLI debugging with the following flag:

pgo version --debug

You can set the REST API URL as follows after a deployment if you are developing on your local host by executing the setip bash function.