Chapter 6. Deploying Service Registry storage in a PostgreSQL database

This chapter explains how to install, configure, and manage Service Registry storage in a PostgreSQL database.

Important

Service Registry storage in PostgreSQL is a Technology Preview feature only. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production.

These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process. For more information about the support scope of Red Hat Technology Preview features, see https://access.redhat.com/support/offerings/techpreview.

6.1. Installing a PostgreSQL database from the OpenShift OperatorHub

If you do not already have a PostgreSQL database Operator installed, you can install a PostgreSQL Operator on your OpenShift cluster from the OperatorHub. The OperatorHub is available from the OpenShift Container Platform web console and provides an interface for cluster administrators to discover and install Operators. For more details, see the OpenShift documentation.

Prerequisites

  • You must have cluster administrator access to an OpenShift cluster.

Procedure

  1. In the OpenShift Container Platform web console, log in using an account with cluster administrator privileges.
  2. Change to the OpenShift project in which Service Registry is installed. For example, from the Project drop-down, select my-project.
  3. In the left navigation menu, click Operators > OperatorHub.
  4. In the Filter by keyword text box, enter PostgreSQL to find an Operator suitable for your environment, for example, Crunchy PostgreSQL for OpenShift or PostgreSQL Operator by Dev4Ddevs.com.
  5. Read the information about the Operator, and click Install to display the Operator subscription page.
  6. Select your subscription settings, for example:

    • Update Channel > stable
    • Installation Mode > A specific namespace on the cluster > my-project
    • Approval Strategy > Manual
  7. Click Install, and wait a few moments until the Operator is ready for use.

    Important

    You must read the documentation from your chosen PostgreSQL Operator for details on how to create and manage your database.

6.2. Configuring Service Registry with PostgreSQL database storage on OpenShift

This section explains how to configure Java Persistence API-based storage for Service Registry on OpenShift using a PostgreSQL database Operator. You can install Service Registry in an existing database or create a new database, depending on your environment. This section shows a simple example using the PostgreSQL Operator by Dev4Ddevs.com.

Prerequisites

Procedure

  1. In the OpenShift Container Platform web console, log in using an account with cluster administrator privileges.
  2. Change to the OpenShift project in which Service Registry and your PostgreSQL Operator are installed. For example, from the Project drop-down, select my-project.
  3. Create a PostgreSQL database for your Service Registry storage. For example, click Installed Operators > PostgreSQL Operator by Dev4Ddevs.com > Create database > YAML.
  4. Edit the database settings as follows:

    • name: Change the value to registry
    • image: Change the value to centos/postgresql-10-centos7
  5. Edit any other database settings as needed depending on your environment, for example:

    apiVersion: postgresql.dev4devs.com/v1alpha1
    kind: Database
    metadata:
      name: registry
      namespace: my-project
    spec:
      databaseCpu: 30m
      databaseCpuLimit: 60m
      databaseMemoryLimit: 512Mi
      databaseMemoryRequest: 128Mi
      databaseName: example
      databaseNameKeyEnvVar: POSTGRESQL_DATABASE
      databasePassword: postgres
      databasePasswordKeyEnvVar: POSTGRESQL_PASSWORD
      databaseStorageRequest: 1Gi
      databaseUser: postgres
      databaseUserKeyEnvVar: POSTGRESQL_USER
      image: centos/postgresql-10-centos7
      size: 1
  6. Click Create Database, and wait until the database is created.
  7. Click Installed Operators > Red Hat Integration - Service Registry > ApicurioRegistry > Create ApicurioRegistry.
  8. Paste in the following custom resource definition, and edit the values for the database url and credentials to match your environment:

    apiVersion: apicur.io/v1alpha1
    kind: ApicurioRegistry
    metadata:
      name: example-apicurioregistry
    spec:
      configuration:
        persistence: "jpa"
        dataSource:
          url: "jdbc:postgresql://SERVICE_NAME.NAMESPACE.svc:5432/"
          # e.g. url: "jdbc:postgresql://acid-minimal-cluster.my-project.svc:5432/"
          userName: "postgres"
          password: "PASSWORD"
          # ^ Optional
  9. Click Create and wait for the Service Registry route to be created on OpenShift.
  10. Click Networking > Route to access the new route for the Service Registry web console. For example:

    http://example-apicurioregistry.my-project.my-domain-name.com/

6.3. Backing up Service Registry PostgreSQL storage

When using Java Persistence API storage in a PostgreSQL database, you must ensure that the data stored by Service Registry is backed up regularly.

SQL Dump is a simple procedure that works with any PostgreSQL installation. This uses the pg_dump utility to generate a file with SQL commands that you can use to recreate the database in the same state that it was in at the time of the dump.

pg_dump is a regular PostgreSQL client application, which you can execute from any remote host that has access to the database. Like any other client, the operations that can perform are limited to the user permissions.

Procedure

  • Use the pg_dump command to redirect the output to a file:

     $ pg_dump dbname > dumpfile

    You can specify the database server that pg_dump connects to using the -h host and -p port options.

  • You can reduce large dump files using a compression tool, such as gzip, for example:

     $ pg_dump dbname | gzip > filename.gz

Additional resources

For details on client authentication, see the PostgreSQL documentation.

6.4. Restoring Service Registry PostgreSQL storage

You can restore SQL Dump files created by pg_dump using the psql utility.

Prerequisites

Procedure

  1. Enter the following command to create the database:

     $ createdb -T template0 dbname
  2. Enter the following command to restore the SQL dump

     $ psql dbname < dumpfile
  3. Run ANALYZE on each database so the query optimizer has useful statistics.