Development Environment

The PostgreSQL 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 4.3.0 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 or OpenShift cluster
  • Once you have cloned the git repository, you will need to download the CentOS 7 repository files and GPG keys and place them in the $PGOROOT/conf directory. You can do so with the following code:
cd $PGOROOT
curl https://api.developers.crunchydata.com/downloads/repo/rpm-centos/postgresql12/crunchypg12.repo > conf/crunchypg12.repo
curl https://api.developers.crunchydata.com/downloads/repo/rpm-centos/postgresql11/crunchypg11.repo > conf/crunchypg11.repo
curl https://api.developers.crunchydata.com/downloads/gpg/RPM-GPG-KEY-crunchydata-dev > conf/RPM-GPG-KEY-crunchydata-dev

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

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.

Code Generation

Code generation is leveraged to generate the clients and informers utilized to interact with the various Custom Resources (e.g. pgclusters) comprising the PostgreSQL Operator declarative API. Code generation is provided by the Kubernetes code-generator project, and the following two Make targets are included within the PostgreSQL Operator project to both determine if any generated code within the project requires an update, and then update that code as needed:

# Check to see if an update to generated code is needed:
make verify-codegen

# Update any generated code:
make update-codegen

Therefore, in the event that a Custom Resource defined within the PostgreSQL Operator API ($PGOROOT/apis/crunchydata.com) is updated, the verify-codegen target will indicate that an update is needed, and the update-codegen target should then be utilized to generate the updated code prior to compiling.

Compile

Please be sure to have your GPG Key and .repo file in the conf directory before proceeding.

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.

Deployment

Now that you have built the PostgreSQL Operator images, you can now deploy them to your Kubernetes cluster. To deploy the image and associated Kubernetes manifests, you can execute the following command:

make deployoperator

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.

Testing

Once the PostgreSQL Operator is deployed, you can run the end-to-end regression test suite interface with the PostgreSQL client. You need to ensure that the pgo client executable is in your $PATH. The test suite can be run using the following commands:

cd $PGOROOT/testing/pgo_cli
GO111MODULE=on go test -count=1 -parallel=2 -timeout=30m -v .

For more information, please follow the testing README in the source repository.

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.