ballerinax/persist.redis Ballerina library

Overview

This module provides Redis database support for the bal persist feature, which provides functionality to store and query data from a Redis database through a data model instead of writing Redis commands.

How to use with bal persist

Since Redis is not the default datastore for bal persist you need to explicitly specify the data store in your application in either of the following ways,

Integrate to bal build

1. Initialize bal persist and integrate to bal build using the following command,

   $ bal persist add --datastore redis --module <module_name>
   

2. After defining the entities, build the application using the following command,

   $ bal build
   

One time generation

1. Initialize bal persist using the following command,

   $ bal persist init
   

2. Generate the persist client using the following command,

   $ bal persist generate --datastore redis --module <module_name>
   

Supported Ballerina data types

The following table lists the Ballerina data types supported by the Redis data store. Following data types will be converted to string when inserting data and converted back to relevent data types in ballerina when retrieving.

Configuration

You need to set a value for the following configuration parameter in the Config.toml file in your project to use the Redis data store.

The following is a sample Config.toml file with the Redis data store configuration. This is generated by the persist generate command.

[<packageName>.<moduleName>.connectionConfig]
connection = "redis://localhost:6379"

[<packageName>.<moduleName>.cacheConfig]
maxAge = -1

Alternatively, you can provide connection parameters instead of the URI as follows.

[<packageName>.<moduleName>.connectionConfig.connection]
host = "localhost"
port = 6379

Currently, the Redis data store only supports global cache configuration at the client level. The maxAge parameter in the cache configuration specifies the maximum age in seconds for cached objects. A value of -1 indicates that objects within the cache have no expiry time, persisting indefinitely until manually removed.

Additionally, you can set values for the advanced configuration parameters in the Config.toml file in your project to use the Redis data store. For more information on these parameters, see the Redis Connector documentation.

Setup guide

Select one of the methods below to set up a Redis server.

Setup a Redis server locally

Install a Redis server on your machine locally by downloading and installing it based on your development platform. See the official Redis documentation.

Setup using docker

Use Docker to create a DB server deployment.

1. Install Docker on your machine if you haven't already.
2. Pull the Redis Docker image from Docker Hub using the command docker pull redis.
3. Run the Redis container as follows docker run -d -p 6379:6379 --name <container-name> redis.

Setup a cloud-based Redis service

Use a cloud-based DB solution such as Google’s Cloud, Amazon’s Web Services, or Microsoft’s Azure database.

1. Visit Redis cloud console.

2. Login using email and password or using one of the Single Sign-On options.

3. Select either Amazon Web Services, Google Cloud, or Microsoft Azure as the database vendor.

4. Select a region and create the database.

5. Find your username, password and the public endpoint

6. Replace the connection parameter in the Config.toml file as below

   connection = "redis://:@"