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#🌱|help-and-getting-started
How to pre-load a PVC with files from the host
# 🌱|help-and-getting-started
q

quaint-librarian-55734

01/11/2023, 4:45 PM
I've been looking for a way to create a persistent volume claim that has files pre-loaded into it from the host machine. I know this can be done using the hostPath parameter on a
volume
module, but since this not supported for real kubernetes clusters, I was trying to find a more portable approach. The use case is that we'd like to load some startup scripts for a containers from a
scripts
folder in our Git repo. Right now, we are using a
configmap
since mounting this as a volume will convert all of the key/values from the
data
section into mounted files - however, this approach forces us to in-line our bash script as yaml text, and this prevents our linters from being able to catch bash scripting issues. Additionally - while I know that this can also be done by specifying a custom Dockerfile which copies in files from the module build directory, we're trying to avoid the "pull image -> copy files/build new image -> republish" cycle that this causes since we have a very large number of containers that are built from a template and are working on reducing the deployment times. Here's a reference template for what I'm trying to do:
Copy code
kind: ModuleTemplate
name: service-template
inputsSchemaPath: schema.json
modules:
  # We'd like to pre-load some scripts into the persistent volume created by this claim
  - name: "${inputs.serviceName}-scripts-pvc"
    type: persistentvolumeclaim
    spec:
      accessModes:
        - ReadWriteOnce
      resources:
        requests:
          storage: 1Gi

  - type: container
    name: ${inputs.serviceName}-container
    image: "${inputs.imageName}"
    services:
      - name: "${inputs.serviceName}-http"
        command:
            - bash
            - /scripts/startup.sh
        volumes:
          - name: scripts-pvc
            containerPath: "/scripts"
            module: "${inputs.serviceName}-scripts-pvc"
q

quaint-dress-831

01/17/2023, 6:06 AM
Hi Brett! I am on vacation from today and delegating to @glamorous-caravan-26619
g

glamorous-caravan-26619

01/18/2023, 2:06 PM
hello @quaint-librarian-55734
looking
hey @quaint-librarian-55734, I made an example here: https://github.com/dmytri/garden-lib-volume in which, I use a utility container called lib with a task that mounts and seeds a volume with a test script, the volume is mounted on a pod called app
q

quaint-librarian-55734

01/19/2023, 5:22 PM
I had a suspicion that something like this would be the approach - thank you so much for the example, this is immensely helpful!
g

glamorous-caravan-26619

01/19/2023, 5:23 PM
I'll make a nice readme tomorrow, but in the mean time: - clone -
garden deploy
-
garden test-lib
- you should see the output of the test script which is mounted on app - then edit
lib/src/scripts/test
-
garden update-lib
-
garden test-lib
(again) - you should now see the changed output with your edit
I should note this will only work for single node setups, for multinode a different storage class will be needed 🙂
q

quaint-librarian-55734

01/19/2023, 5:39 PM
Yep - understood
g

glamorous-caravan-26619

01/26/2023, 4:47 PM
hey @quaint-librarian-55734, I made another example if using artifacts, build dependencies and a build command on a exec module to just bake the scripts into a consuming container rather than using a volume to share them, in most cases this feels more like The Kubernetes Way (tm) as sharing the volume kinda breaks the idea of immutability
it also works fine in all set-ups, not requiring a storage class support
In which we use @garden_io to build assets in a library-builder container and bake them into an app container that uses them. https://github.com/dmytri/garden-lib-artifacts
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