Upload file with new timestamp

[mleonhard]

Terraform Version

Terraform v0.12.20
+ provider.digitalocean v1.14.0
+ provider.docker v2.7.0   <--- Latest version as of 2012-03-12
+ provider.local v1.4.0
+ provider.null v2.1.2
+ provider.random v2.2.1
+ provider.tls v2.1.1
+ provider.twilio (unversioned)

Affected Resource(s)

• docker_container

Terraform Configuration Files

resource "docker_container" "grafana" {
  name = "grafana"
  user = "1000"
  upload {
    file = "/etc/grafana/provisioning/dashboards/containers.json"
    content = file("${path.module}/containers.json")
  }
  ...
}

Expected Behavior

I need Terraform to update the timestamp of the uploaded file when it changes the file's contents.

Actual Behavior

Terraform currently uploads the file and sets its timestamp to 0. It also sets its owner to root. A non-root container cannot update the file timestamp.

root@staging19:~# docker exec -t -i grafana sh
/usr/share/grafana $ ls -alF /etc/grafana/provisioning/dashboards/containers.json
-rw-r--r--    1 root     root         32101 Jan  1  1970 /etc/grafana/provisioning/dashboards/containers.json
/usr/share/grafana $ touch /etc/grafana/provisioning/dashboards/containers.json
touch: /etc/grafana/provisioning/dashboards/containers.json: Permission denied
/usr/share/grafana $ 

[mleonhard]

I need this because Grafana reloads dashboard files only when their timestamp has increased. It stores the timestamp in its database. Grafana's dashboards.fileReader.saveDashboard()

[mleonhard]

I found two workarounds:

1. Include a hash of the file contents in the filename:

   locals {
    dashboard_json = file("${path.module}/containers.json")
   }
   resource "docker_container" "grafana" {
    upload {
      file = "/etc/grafana/provisioning/dashboards/containers.json"
      content = file("${path.module}/containers.json")
      file = "/etc/grafana/provisioning/dashboards/dashboard.${md5(local.dashboard_json)}.json"
      content = local.dashboard_json
    }
    ...
   }

2. Put the file in the image. This works as long as the dashboard doesn't require any config data from Terraform.