Deploying an Application from a Chart

Constraints

• The number of charts that can be uploaded by a single user is limited. The value displayed on the console of each region is the allowed quantity.
• CCE uses Helm v3.8.2 and allows uploading Helm v3 chart packages.
• A chart with multiple versions consumes the same amount of portion of chart quota.
• Users with chart operation permissions can perform multiple operations on clusters. Therefore, exercise caution when assigning users the chart lifecycle management permissions, including uploading charts and creating, deleting, and updating chart releases.

Chart Specifications

The Redis workload is used as an example to illustrate the chart specifications.

• Naming Requirement

  A chart package is named in the format of {name}-{version}.tgz, where {version} indicates the version number in the format of Major version number.Minor version number.Revision number, for example, redis-0.4.2.tgz.

  

  The chart name {name} can contain a maximum of 64 characters.

  The version number must comply with the semantic versioning rules.

  • The main and minor version numbers are mandatory, and the revision number is optional.
  • The major and minor version numbers and revision number must be integers, greater than or equal to 0, and less than or equal to 99.
• Directory Structure

  The directory structure of a chart is as follows:

  redis/
    templates/
    values.yaml
    README.md
    Chart.yaml
    .helmignore

  As listed in Table 1, the parameters marked with * are mandatory.

  Table 1 Parameters in the directory structure of a chart

  Parameter	Description
  * templates	Stores all templates.
  * values.yaml	Describes configuration parameters required by templates. NOTICE: Make sure that the image address set in the values.yaml file is the same as the image address in the container image repository. Otherwise, an exception occurs when you create a workload, and the system displays a message indicating that the image fails to be pulled. To obtain the image address, perform the following operations: Log in to the CCE console. In the navigation pane on the left, choose Image Repository to access the SWR console. Choose My Images > Private Images and click the name of the uploaded image. On the Image Tags tab, obtain the image address from the pull command. You can click to copy the command in the Image Pull Command column.
  README.md	A markdown file, including: The workload or services provided by the chart. Prerequisites for running the chart. Configurations in the values.yaml file. Information about chart installation and configuration.
  * Chart.yaml	Basic information about the chart. Note: The API version of Helm v3 is switched from v1 to v2.
  .helmignore	Files or data that does not need to read templates during workload installation.

Uploading a Chart

1. Log in to the CCE console and click the cluster name to access the cluster console. In the navigation pane on the left, choose App Templates. Then click Upload Chart in the upper right corner.
2. Click Select File, select the chart to be uploaded, and click Upload.

Creating a Release

1. Log in to the CCE console and click the cluster name to access the cluster console. In the navigation pane on the left, choose App Templates.
2. On the My Charts tab, click Install of the target chart.
3. Set workload installation parameters by referring to Table 2.

   Table 2 Installation parameters

   Parameter	Description
   Instance	Unique name of the chart release.
   Namespace	Namespace to which the workload will be deployed.
   Select Version	Version of a chart.
   Configuration File	You can import and replace the values.yaml file or directly edit the chart parameters online. NOTE: An imported values.yaml file must comply with YAML specifications, that is, KEY:VALUE format. The fields in the file are not restricted. The key value of the imported values.yaml must be the same as that of the selected chart package. Otherwise, the values.yaml does not take effect. That is, the key cannot be changed. Click Select File. Select the corresponding values.yaml file and click Open.

4. Click Install.

   On the Releases tab, you can view the installation status of the release.

Upgrading a Chart-based Workload

1. Log in to the CCE console and click the cluster name to access the cluster console. In the navigation pane on the left, choose App Templates. Then click the Releases tab.
2. Click Upgrade in the row where the desired workload resides and set the parameters for the workload.
3. Select a chart version for Chart Version.
4. Follow the prompts to modify the chart parameters. Click Upgrade and then click Submit.
5. Click Back to Release List. If the chart status changes to Upgrade successful, the workload is successfully upgraded.

Rolling Back a Chart-based Workload

1. Log in to the CCE console and click the cluster name to access the cluster console. In the navigation pane on the left, choose App Templates. Then click the Releases tab.
2. Click More > Roll Back for the workload to be rolled back, select the workload version, and click Roll back to this version.

   In the workload list, if the status is Rollback successful, the workload is rolled back successfully.

Uninstalling a Chart-based Workload

1. Log in to the CCE console and click the cluster name to access the cluster console. In the navigation pane on the left, choose App Templates. Then click the Releases tab.
2. Click More > Uninstall next to the release to be uninstalled, and click Yes. Exercise caution when performing this operation because releases cannot be restored after being uninstalled.