About Using the ttclassic Helm Chart

The ttclassic Helm chart contains the information needed to deploy replicated and non-replicated TimesTen database in your Kubernetes namespace. There are many customizations available to meet your preferred configuration. There are variables specific to the ttclassic chart for such customizations. The About Creating TimesTen Databases section discusses some of these customizations. For additional customizations, see The ttclassic Chart.

The TimesTen Operator provides metadata files to further customize your database. One file of particular interest is testUser. After TimesTen is deployed, you can use the helm test command to test TimesTen. The test operation requires that a TimesTen test user exist in the TimesTen database. This user connects to the database as part of the testing process. This user must be defined before installing the ttclassic chart. The TimesTen Operator provides the testUser metadata file for this purpose. The file contains one line of the form:

testuser/testuserpassword

where testuser is the name of the TimesTen user to use for testing TimesTen and testuserpassword is the password for this test user. For details, see Use Configuration Metadata.

If you are using Kubernetes ConfigMaps or Secrets as the facilities to place metadata files into the TimesTen containers, you do not need to create them. Instead, when you install the ttclassic chart, the ConfigMaps and Secrets are automatically created as part of the installation process. To facilitate the process, you must create a directory within the ttclassic chart directory tree and create the metadata files in this directory. There are examples later in this section that show you how to do this.

After you decide your configurations needs and review the variables you are using for these customizations, you have the following options for supplying these variables as part of the ttclassic chart's installation process:

Create a YAML file for the variables. When installing the ttclassic chart, pass this YAML file to the helm install command by specifying the -f option.
Specify the variables on the command line by running the helm install command with the --set option.

The examples use a YAML file. For specifics about these options including the syntax, see https://helm.sh/docs/intro/using_helm/ in the Helm documentation.

The examples show you how to use the ttclassic Helm chart to define and deploy replicated and non-replicated TimesTen databases. Both examples use the same set of metadata files and both use Kubernetes ConfigMaps to get the metadata files into the tt containers.

For simplicity, let's create the metadata files and ConfigMaps used in the examples. For complete details about metadata files, see Use Configuration Metadata and Populate the /ttconfig Directory.

On your development host, change to the ttclassic directory. In this example, the directory location is kube_files/helm/ttclassic.
```
cd kube_files/helm/ttclassic
```
Create a directory for the metadata files.
```
mkdir cm
```
Create metadata files in the directory used for the metadata files (cm in this example). These metadata files are used in the examples throughout the chapter.
1. Create the testUser file.
```
vi cm/testUser

sampletestuser/sampletestuserpwd1
```
2. Create the db.ini file.
```
vi cm/db.ini

PermSize=200
DatabaseCharacterSet=AL32UTF8
```
3. Create the adminUser file.
```
vi cm/adminUser

adminuser/adminuserpwd
```
4. Create the schema.sql file.
```
vi cm/schema.sql

create table adminuser.emp (id number not null primary key, name char (32));
```

You created the metadata files and the directory for them. Save the location of the directory. You need it later.