Custom Charts
Devtron includes predefined helm charts that cover the majority of use cases. For any use case not addressed by the default helm charts, you can upload your own helm chart and use it as a custom chart in Devtron.
Who can upload a custom chart - Super admins
Who can use the custom chart - All users
A super admin can upload multiple versions of a custom helm chart.
Prerequisites
A valid helm chart, which contains
Chart.yaml
file with name and version fields.Image descriptor template file -
.image_descriptor_template.json
.Custom chart packaged in the
*.tgz
format.
1. How to create a helm chart
Chart.yaml
is the metadata file that gets created when you create a helm chart.
Field | Description |
---|---|
Name | Required. Name of the helm chart. |
Version | Required. This is the chart version. Update this value for each new version of the chart. |
Description | Optional. Description of the chart. |
2. Create the image descriptor template file - .image_descriptor_template.json
.image_descriptor_template.json
It's a GO template file that should produce a valid JSON
file upon rendering. This file is passed as the last argument in helm install -f myvalues.yaml -f override.yaml
command.
Place the .image_descriptor_template.json
file in the root directory of your chart.
You can use the following variables in the helm template (all the placeholders are optional):
The values from the CD deployment pipeline are injected at the placeholder specified in the
.image_descriptor_template.json
template file.
Field | Description |
---|---|
image_tag | The build image tag |
image | Repository name |
pipelineName | The CD pipeline name created in Devtron |
releaseVersion | Devtron's internal release number |
deploymentType | Deployment strategy used in the pipeline |
app | Application's ID within the Devtron ecosystem |
env | Environment used to deploy the chart |
appMetrics | For the App metrics UI feature to be effective, include the |
For example:
To create a template file to allow Devtron to only render the repository name and the tag from the CI/CD pipeline that you created, edit the
.image_descriptor_template.json
file as:
3. Package the custom chart in the *.tgz
format
*.tgz
formatBefore you begin, ensure that your helm chart includes both
Chart.yaml
(withname
andversion
fields) and.image_descriptor_template.json
files.
The helm chart to be uploaded must be packaged as a versioned archive file in the format - <helm-chart-name>-vx.x.x.tgz
.
The above command will create a my-custom-chart-0.1.0.tgz
file.
Uploading a custom chart
A custom chart can only be uploaded by a super admin.
On the Devtron dashboard, select Global Configurations > Custom charts.
Select Import Chart.
Choose Select tar.gz file... and upload the packaged custom chart in the
*.tgz
format.
The chart is being uploaded and validated. You may also Cancel upload if required.
Validation
The uploaded archive will be validated against:
Supported archive template should be in
*.tgz
format.Chart.yaml
must include the name and the version number.image_descriptor_template.json
file should be present and the field format must match the format listed in the image builder template section.
The following are the validation results:
Validation status | Description | User action |
---|---|---|
Success | The files uploaded are validated. | Enter a description for the chart and select Save or Cancel upload. |
Unsupported template | The archive file do not match the required template. | Upload another chart or Cancel upload. |
New version detected | You are uploading a newer version of an existing chart | Enter a Description and select Save to continue uploading, or Cancel upload. |
Already exists | There already exists a chart with the same version. |
|
View the custom charts
All users can view the custom charts.
To view a list of available custom charts, go to Global Configurations > Custom charts page.
The charts can be searched with their name, version, or description.
New custom charts can be uploaded by selecting Upload chart.
Use the custom chart in an application
The custom charts can be used from the Deployment Template section.
Info:
The deployment strategy for a custom chart is fetched from the custom chart template and cannot be configured in the CD pipeline.
Last updated