Template Strings
Template Strings are strings which are dynamically replaced by Preview during a deploy, allowing you to inject environment-specific values into your deployment.
Preview supports the use of Template Strings in both for all chart values and Kubernetes manifest files under the
./preview directory.For example, it is recommended to use the
PREVIEWHQ_HOSTNAME as part of your application's Ingress specification:# .preview/chart-values/
ingress:
enabled: true
annotations:
kubernetes.io/tls-acme: "true"
path: /
hosts:
- host: ${PREVIEWHQ_HOSTNAME}
paths:
- /
tls:
- secretName: tls-secret
hosts:
- ${PREVIEWHQ_CLUSTER_HOSTNAME}
- ${PREVIEWHQ_HOSTNAME}
There are 2 sets of Template Strings which can be utilized: one static set across all builds, and one set that is dynamically build based on image builds.
Template String | Description | Example |
PREVIEWHQ_HOSTNAME | The hostname of the deployment, which will point to the root | my-pr-branch.nrmitchi.envs.dev |
PREVIEWHQ_CLUSTER_HOSTNAME | The hostname of the cluster which the deployment is deployed on | nrmitchi.envs.dev |
PREVIEWHQ_NAMESPACE | The namespace which the deployment is deployed in to | my-pr-branch |
PREVIEWHQ_REVISION | The git hash being deployed | |
PREVIEWHQ_IMAGE_REPOSITORY | The URL of the Preview-provided Docker image repository that | |
For each addition image specified in the
images block of the configuration, Preview injects a PREVIEWHQ_CUSTOM_IMAGE_TAG_{} string, which is the Docker tag which was used for that custom build within the Docker image registry.For example, if
images is as follows:images:
- name: frontend
dockerfile: ./src/react/Dockerfile
context: ./src/react
- name: backend
dockerfile: ./src/flask/Dockerfile
context: ./src/flask
The the following additional Templates Strings are available:
PREVIEWHQ_CUSTOM_IMAGE_TAG_FRONTENDPREVIEWHQ_CUSTOM_IMAGE_TAG_BACKEND
Last modified 2yr ago