docker-nexus-backup

A container image for backing-up Sonatype Nexus Repository Manager data into GCP Cloud Storage.

Introduction

Nexus Repository Manager can be configured to back-up its internal database on a regular basis. However, this process does not take blob stores into account. Furthermore, the back-ups are persisted in the local disk alone, meaning if the disk is lost, the back-ups are lost too.

This tool addresses these two shortcomings by backing-up the default blob store and then uploading everything to GCS, including the database back-up Nexus previously created. This procedure is automatically triggered by touchinging ${NEXUS_BACKUP_DIRECTORY}/.backup.

When the back-up starts, a lock file is created so that no two backup processes run simultaneously. This lock file is removed automatically after a successful backup. A warning message is displayed whenever a lock file has been present for more than twelve hours (meaning a failed backup), and the lock file is removed so that further back-ups can be made.

Compatibility with Nexus

Starting from version 1.4.0, docker-nexus-backup is only compatible with Nexus 3.8.0 and above. Users requiring support for earlier versions of Nexus must use version 1.3.0.

Run

The simplest way to run the container is to assume the default configuration (check below for the default configuration):

docker run --detach                                               \
           --name nexus-backup                                    \
           --volume /path/to/nexus-data:/nexus-data               \
           --volume /path/to/nexus-data-backup:/nexus-data/backup \
           quay.io/travelaudience/docker-nexus-backup:1.4.0

You can change, for example, the repositories which to lock during backup and the target Google Cloud Storage bucket by specifing the correct values as environment variables:

docker run --detach \
           --env OFFLINE_REPOS="docker-hosted maven-central maven-public maven-releases maven-snapshots" \
           --env TARGET_BUCKET="gs://my-fancy-bucket/" \
           --name nexus-backup \
           --volume /path/to/nexus-data:/nexus-data \
           --volume /path/to/nexus-data-backup:/nexus-data/backup \
           quay.io/travelaudience/docker-nexus-backup:1.4.0

Inside Google Container Engine

Your Google Container Engine cluster must be created with Cloud Storage read-write permissions enabled (https://www.googleapis.com/auth/devstorage.read_write scope).

Outside Google Container Engine

If you're running this image, or any other container image based on this, outside GKE you will need to create a service account with the "Storage Object Creator" and "Storage Object Viewer" permissions, download the newly furnished private key file in JSON format, mount it in the container and specify the mount path using the CLOUD_IAM_SERVICE_ACCOUNT_KEY_PATH environment variable.

Environment Variables

This image can be configured by means of environment variables. You will most probably want to customize NEXUS_AUTHORIZATION, NEXUS_LOCAL_HOST_PORT and TARGET_BUCKET to suit your use case, while most other environment variables will require no changes.

Variable	Description	Default
`CLOUD_IAM_SERVICE_ACCOUNT_KEY_PATH`	(Optional) The path to a service account key file with which to authenticate against GCS.	(empty)
`NEXUS_AUTHORIZATION`	The authorization header to use when calling the Nexus API.	`Basic YWRtaW46YWRtaW4xMjMK`
`NEXUS_BACKUP_DIRECTORY`	The directory to which the Nexus 'backup-2' task will produce its output.	`/nexus-data/backup`
`NEXUS_DATA_DIRECTORY`	The Nexus data directory.	`/nexus-data`
`NEXUS_LOCAL_HOST_PORT`	The host and port at which Nexus can be reached.	`localhost:8081`
`OFFLINE_REPOS`	The names of the repositories must be taken down to achieve a consistent backup.	`maven-central maven-public maven-releases maven-snapshots`
`TARGET_BUCKET`	The name of the GCS bucket to which the resulting backups will be uploaded.	`gs://nexus-backup`
`GRACE_PERIOD`	The amount of time in seconds to wait between stopping repositories and starting the upload.	`60`