Hi all,
I'm writing a blueprint in which a "leader" entity must be able to SSH
to a group of followers. I'm canvassing for opinions on a clean way to
express this.
At the moment I have:
services:
- id: leader
type: org.apache.brooklyn.entity.software.base.EmptySoftwareProcess
brooklyn.config:
preInstallCommand: |
test -f ~/.ssh/id_rsa.pub || (mkdir -p ~/.ssh ; ssh-keygen -t rsa
-b 4096 -f ~/.ssh/id_rsa -N '')
brooklyn.initializers:
- type: org.apache.brooklyn.core.sensor.ssh.SshCommandSensor
brooklyn.config:
name: ssh.publicKey
command: cat ~/.ssh/id_rsa.pub 2>/dev/null
period: 1m
- id: group
type: org.apache.brooklyn.entity.group.DynamicCluster
brooklyn.config:
initialSize: 1
memberSpec:
$brooklyn:entitySpec:
type: org.apache.brooklyn.entity.software.base.EmptySoftwareProcess
brooklyn.config:
# Allow SSH from leader.
preInstallCommand:
$brooklyn:formatString:
- "mkdir -p ~/.ssh && echo '%s' >> ~/.ssh/authorized_keys"
-
$brooklyn:component("leader").attributeWhenReady("ssh.publicKey")
This is more or less satisfactory but I don't like the repeated polling
for id_rsa.pub. Is there a case for a sensor that stops executing once
some condition is met? In the case above it would either be a zero exit
code or a non-empty stdout.
Sam
