Exec Action

Exec action allows you to executes a command or a script file on the target host. The type of scripts executed include:

• Bash scripts
• Powershell scripts

scale-deployment.yaml
apiVersion: mission-control.flanksource.com/v1
kind: Playbook
metadata:
  name: scale-deployment
spec:
  description: Scale Deployment
  configs:
    - types:
        - Kubernetes::Deployment
  parameters:
    - name: replicas
      label: The new desired number of replicas.
  actions:
    - name: kubectl scale
      exec:
        script: |
          kubectl scale --replicas={{.params.replicas}} \
            --namespace={{.config.tags.namespace}} \
            deployment {{.config.name}}

Field	Description	Scheme
name*	Step Name	string
exec	Exec Action	Exec
delay	A delay before running the action e.g. 8h	Duration or CEL with Playbook Context
filter	Conditionally run an action	CEL with Playbook Context
runsOn	Which runner (agent) to run the action on	[]Agent
templatesOn	Where templating (and secret management) of actions should occur	host or agent
timeout	Timeout on this action.	Duration

Exec

Field	Description	Scheme
script*	The script to execute	string
artifacts	Artifacts produced by the action	Artifacts
checkout	Checkout a git repository before running the script	Checkout
connections	Connections used by the action	Connections
env	Environment variables to set during execution	[]EnvVar

Output

Field	Description	Scheme
args	Args for the command	[]string
exitCode	Exit code of command	int
path	Path for command context	string
stderr	Stderr of command	string
stdout	Stdout of command	string

Templating

Scripts are templatable with Go Templates

exec:
        script: kubectl rollout release deployment -n $(.config.tags.namespace) $(.conf

Shell Language

Use a shebang (#!) line to choose a different shell (python, bash and pwsh are included in the base image)

exec:
  script: |
    #! pwsh
    Get-Items | ConvertTo-JSON

Switching scripting language

Use a shebang (#!) line to choose a different shell (python, bash and pwsh are included in the base image)

exec:
  script: |
    #! pwsh
    Get-Items | ConvertTo-JSON

Escaping templates in Helm Charts

If you need to pass a template through a Helm Chart and prevent Helm from templating you need to escape it:

{{`{{ .secret }}`}}

Alternatively change the templating delimiters

Multiline handling with YAML

If you are using a YAML multiline string use | and not > which strips newlines.

Instead of:

exec:
  script: >
    #! pwsh
    Get-Items | ConvertTo-JSON

Do this:

exec:
  script: |
    #! pwsh
    Get-Items | ConvertTo-JSON

Changing templating delimiters

The template delimiters can be changed from the defaults of $() and {{}} with gotemplate comments

exec:
  script: |
    #! pwsh
    # gotemplate: left-delim=$[[ right-delim=]]
    $message = "$[[.config.name]]"
    Write-Host "{{  $message }}"
    Write-Host  @{ Number = 1; Shape = "Square"; Color = "Blue"} | ConvertTo-JSON

Connections

Exec connections allow you to specify credentials for a list of CLI tools that are needed by your scripts. Eg: You can specify the AWS connection name and the credential files along with the necessary environment variables will be setup on the host running the script.

Field	Description	Scheme
aws	AWS connection	AWSConnection
azure	Azure connection	AzureConnection
eksPodIdentity	EKSPodIdentity when enabled will allow access to AWS_* env vars	bool
fromConfigItem	Fetch connection from a Config item's scraper	uuid
gcp	GCP connection	GCPConnection
kubernetes	Kubernetes connection	KubernetesConnection
serviceAccount	ServiceAccount when enabled will allow access to KUBERNETES env vars	bool

Artifacts

exec-artifact.yaml
apiVersion: mission-control.flanksource.com/v1
kind: Playbook
metadata:
  name: exec-artifact
spec:
  description: Simple script to generate an artifact
  configs:
    - types: 
        - EC2 Instance
      labelSelector: "telemetry=enabled"
  actions:
    - name: 'Generate artifact'
      exec:
        script: echo "hello world" > /tmp/output.txt
        artifacts:
          - path: /tmp/output.txt
    

Field	Description	Type	Required
path	Path or glob.	string	true

Git Checkout

exec-checkout.yaml
apiVersion: mission-control.flanksource.com/v1
kind: Playbook
metadata:
  name: read-git-repository
spec:
  description: Clones the git repository and reads the first line of the file
  configs:
    - types:
        - AWS::EKS::Cluster
  actions:
    - name: Clone and read go.sum
      exec:
        script: head -n 1 $READ_FILE
        env:
          - name: READ_FILE
            value: go.sum
        checkout:
          url: https://github.com/flanksource/artifacts
          connection: connection://github/aditya-all-access

      
  

Field	Description	Scheme
destination	Destination is the full path to where the contents of the URL should be downloaded to. If left empty, the sha256 hash of the URL will be used as the dir name
connection	The connection url to use, mutually exclusive with username and password	Connection
url	If connection is specified and it also includes a url, this field will take precedence	string
certificate		EnvVar
username		EnvVar
password		EnvVar

Action Result

Field	Description	Schema
stdout		string
stderr		string
exitCode	Process exit code	int

Templating

CEL Expressions

The following variables can be used within the CEL expressions of filter, if, delays and parameters.default:

Field	Description	Schema
config	Config passed to the playbook	ConfigItem
component	Component passed to the playbook	Component
check	Canary Check passed to the playbook	Check
playbook	Playbook passed to the playbook	Playbook
run	Current run	Run
params	User provided parameters to the playbook	map[string]any
request	Webhook request	Webhook Request
env	Environment variables defined on the playbook	map[string]any
user.name	Name of the user who invoked the action	string
user.email	Email of the user who invoked the action	string
agent.id	ID of the agent the resource belongs to.	string
agent.name	Name of the agent the resource belongs to.	string

Conditionally Running Actions

Playbook actions can be selectively executed based on CEL expressions. These expressions must either return

• a boolean value (true indicating run the action & skip the action otherwise)
• or a special function among the ones listed below

Function	Description
always()	run no matter what; even if the playbook is cancelled/fails
failure()	run if any of the previous actions failed
skip()	skip running this action
success()	run only if all previous actions succeeded (default)
timeout()	run only if any of the previous actions timed out

delete-kubernetes-pod.yaml
---
apiVersion: mission-control.flanksource.com/v1
kind: Playbook
metadata:
  name: notify-send-with-filter
spec:
  parameters:
    - name: message
      label: The message for notification
      default: '{{.config.name}}'
  configs:
    - types: 
        - Kubernetes::Pod
  actions:
    - name: Send notification
      exec:
        script: notify-send "{{.config.name}} was created"
    - name: Bad script
      exec:
        script: deltaforce
    - name: Send all success notification
      if: success() # this filter practically skips this action as the second action above always fails
      exec:
        script: notify-send "Everything went successfully"
    - name: Send notification regardless
      if: always()
      exec:
        script: notify-send "a Pod config was created"

Defaulting Parameters

delete-kubernetes-pod.yaml
apiVersion:
  mission-control.flanksource.com/v1
  kind: Playbook
  metadata:
    name: edit
  spec:
    title: 'Edit Kustomize Resource'
    icon: flux
    parameters:
    - default: 'chore: update $(.config.type)/$(.config.name)'
      name: commit_message

Go Templating

When templating actions with Go Templates, the context variables are available as fields of the template's context object . eg .config, .user.email

Templating Actions

delete-kubernetes-pod.yaml
apiVersion: mission-control.flanksource.com/v1
kind: Playbook
metadata:
  name: scale-deployment
spec:
  description: Scale Deployment
  configs:
    - types:
        - Kubernetes::Deployment
  parameters:
    - name: replicas
      label: The new desired number of replicas.
  actions:
    - name: kubectl scale
      exec:
        script: |
          kubectl scale --replicas={{.params.replicas}} \
            --namespace={{.config.tags.namespace}} \
            deployment {{.config.name}}

Functions

Function	Description	Return
getLastAction()	Returns the result of the action that just run	Action Specific
getAction({action})	Return the result of a specific action	Action Specific

Printing out Results

Reusing Action Results

action-results.yaml
apiVersion: mission-control.flanksource.com/v1
kind: Playbook
metadata:
  name: use-previous-action-result
spec:
  description: Creates a file with the content of the config
  configs:
    - types:
        - Kubernetes::Pod
  actions:
    - name: Fetch all changes
      sql:
        query: SELECT id FROM config_changes WHERE config_id = '{{.config.id}}'
        driver: postgres
        connection: connection://postgres/local
    - name: Send notification
      if: 'last_result().count > 0'
      notification:
        title: 'Changes summary for {{.config.name}}'
        connection: connection://slack/flanksource
        message: |
          {{$rows:=index last_result "count"}}
          Found {{$rows}} changes