docs/content/v2.0/operations/operation.md

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---
title: Operations
weight: 110
state: alpha
alphaVersion: 2.0
description: Run function pipelines once to completion
---
An `Operation` runs a function pipeline once to completion to perform operational
tasks that don't fit the typical resource creation pattern. Unlike compositions
that continuously reconcile desired state, Operations focus on tasks like
backups, rolling upgrades, configuration validation, and scheduled maintenance.
## How operations work
Operations are like Kubernetes Jobs - they run once to completion rather than
continuously reconciling. Like compositions, Operations use function pipelines
to implement their logic, but they're designed for operational workflows
instead of resource composition.
```yaml
apiVersion: ops.crossplane.io/v1alpha1
kind: Operation
metadata:
name: backup-database
spec:
mode: Pipeline
pipeline:
- step: create-backup
functionRef:
name: function-database-backup
input:
apiVersion: fn.crossplane.io/v1beta1
kind: DatabaseBackupInput
database: production-db
retentionDays: 30
```
When you create this Operation, Crossplane:
1. **Validates** the operation and its function dependencies
2. **Executes** the function pipeline step by step
3. **Applies** any resources the functions create or change
4. **Updates** the Operation status with results and completion state
{{<hint "important">}}
Operations are an alpha feature. You must enable them by adding
`--enable-operations` to Crossplane's arguments.
{{</hint>}}
## Key characteristics
- **Runs once to completion** (like Kubernetes Jobs)
- **Uses function pipelines** (like Compositions)
- **Can create or change any Kubernetes resources**
- **Provides detailed status and output from each step**
- **Supports retry on failure with configurable limits**
## Operation functions vs composition functions
Operations and compositions both use function pipelines, but with important
differences:
**Composition Functions:**
- **Purpose**: Create and maintain resources
- **Lifecycle**: Continuous reconciliation
- **Input**: Observed composite resources
- **Output**: Desired composed resources
- **Ownership**: Creates owner references
**Operation Functions:**
- **Purpose**: Perform operational tasks
- **Lifecycle**: Run once to completion
- **Input**: Required resources only
- **Output**: Any Kubernetes resources
- **Ownership**: Force applies without owners
Functions can support both modes by declaring the appropriate capabilities in
their package metadata. Function authors declare this in the `crossplane.yaml`
file when building the function package:
```yaml
apiVersion: meta.pkg.crossplane.io/v1
kind: Function
metadata:
name: my-function
spec:
capabilities:
- composition
- operation
```
This allows Crossplane to know which modes the function supports and avoid
trying to use a composition-only function for operations.
## Common use cases
{{<hint "note">}}
The following examples use hypothetical functions for illustration. At launch,
only function-python supports operations.
{{</hint>}}
### Rolling upgrades
Use Operations for controlled rolling upgrades:
```yaml
apiVersion: ops.crossplane.io/v1alpha1
kind: Operation
metadata:
name: cluster-upgrade
spec:
mode: Pipeline
pipeline:
- step: rolling-upgrade
functionRef:
name: function-cluster-upgrade
input:
apiVersion: fn.crossplane.io/v1beta1
kind: ClusterUpgradeInput
targetVersion: "1.28"
batches: [0.25, 0.5, 1.0] # 25%, 50%, then 100%
healthChecks: [Synced, Ready]
```
### One-time maintenance
Use Operations for specific maintenance tasks:
```yaml
apiVersion: ops.crossplane.io/v1alpha1
kind: Operation
metadata:
name: certificate-rotation
spec:
mode: Pipeline
pipeline:
- step: rotate-certificates
functionRef:
name: function-cert-rotation
input:
apiVersion: fn.crossplane.io/v1beta1
kind: CertRotationInput
targetCertificates:
matchLabels:
rotate: "true"
```
## Advanced configuration
### Retry behavior
Operations automatically retry when they fail. Configure the retry limit to
control how often attempts occur:
```yaml
apiVersion: ops.crossplane.io/v1alpha1
kind: Operation
metadata:
name: resilient-operation
spec:
retryLimit: 10 # Try up to 10 times before giving up (default: 5)
mode: Pipeline
pipeline:
- step: flaky-task
functionRef:
name: function-flaky-task
input:
apiVersion: fn.crossplane.io/v1beta1
kind: FlakyTaskInput
# Task that might fail due to temporary issues
timeout: "30s"
```
**Retry behavior:**
- Each retry resets the entire pipeline - if step 2 of 3 fails, the retry
starts from step 1
- Operations use exponential backoff: 1&nbsp;s, 2&nbsp;s, 4&nbsp;s, 8&nbsp;s, 16&nbsp;s, 32&nbsp;s, then 60&nbsp;s
max
- Operations track the number of failures in `status.failures`
- After reaching `retryLimit`, the Operation becomes
`Succeeded=False`
### Credentials
Operations can provide credentials to functions through Secrets:
```yaml
apiVersion: ops.crossplane.io/v1alpha1
kind: Operation
metadata:
name: secure-backup
spec:
mode: Pipeline
pipeline:
- step: backup-with-credentials
functionRef:
name: function-backup
credentials:
- name: backup-creds
source: Secret
secretRef:
namespace: crossplane-system
name: backup-credentials
key: api-key
- name: database-creds
source: Secret
secretRef:
namespace: crossplane-system
name: database-credentials
key: connection-string
input:
apiVersion: fn.crossplane.io/v1beta1
kind: BackupInput
destination: s3://my-backup-bucket
```
### Multiple pipeline steps
Complex operations can use multiple pipeline steps:
```yaml
apiVersion: ops.crossplane.io/v1alpha1
kind: Operation
metadata:
name: multi-step-deployment
spec:
mode: Pipeline
pipeline:
- step: validate-config
functionRef:
name: function-validator
input:
apiVersion: fn.crossplane.io/v1beta1
kind: ValidatorInput
configName: app-config
- step: backup-current
functionRef:
name: function-backup
input:
apiVersion: fn.crossplane.io/v1beta1
kind: BackupInput
target: current-deployment
- step: deploy-new-version
functionRef:
name: function-deploy
input:
apiVersion: fn.crossplane.io/v1beta1
kind: DeployInput
image: myapp:v2.0.0
strategy: rollingUpdate
- step: verify-health
functionRef:
name: function-health-check
input:
apiVersion: fn.crossplane.io/v1beta1
kind: HealthCheckInput
timeout: 300s
healthEndpoint: /health
```
### RBAC permissions
If your Operation needs to access resources that Crossplane doesn't have
permissions for by default, create a ClusterRole that aggregates to
Crossplane:
```yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
name: operation-additional-permissions
labels:
rbac.crossplane.io/aggregate-to-crossplane: "true"
rules:
# Additional permissions for Operations
- apiGroups: ["networking.k8s.io"]
resources: ["ingresses"]
verbs: ["get", "list", "patch", "update"]
- apiGroups: [""]
resources: ["persistentvolumes"]
verbs: ["get", "list"]
# Add other resources your Operations need to access
```
This ClusterRole is automatically aggregated to Crossplane's main
ClusterRole, giving the Crossplane service account the permissions needed
for your Operations.
{{<hint "note">}}
The [RBAC manager]({{<ref "../guides/pods#rbac-manager-pod">}}) automatically
grants Crossplane access to Crossplane resources (MRs, XRs, etc.). You
only need to create more ClusterRoles for other Kubernetes resources
that your Operations need to access.
For more details on RBAC configuration, see the
[Compositions RBAC documentation]({{<ref "../composition/compositions#grant-access-to-composed-resources">}}).
{{</hint>}}
### Function response cache
{{<hint "note" >}}
Function response caching is an alpha feature. Enable it by setting the
`--enable-function-response-cache` feature flag.
{{< /hint >}}
Operations can use function response caching to improve performance
for operations that:
- Call the same functions often with identical inputs
- Use functions that perform expensive computations or external API calls
- Run frequently through CronOperation or WatchOperation
The cache works the same way as for Compositions - function responses with
time to live values cache and reuse identical requests until
they expire.
Function response caching helps Operations that:
- Validate configurations using expensive checks
- Query external systems for status information
- Perform complex calculations that don't change frequently
For cache configuration details, see the
[Function response cache documentation]({{<ref "../composition/compositions#function-response-cache">}}).
### Required resources
Operations can preload resources for functions to access:
```yaml
apiVersion: ops.crossplane.io/v1alpha1
kind: Operation
metadata:
name: resource-aware-operation
spec:
mode: Pipeline
pipeline:
- step: process-deployment
functionRef:
name: function-processor
requirements:
requiredResources:
- requirementName: app-deployment
apiVersion: apps/v1
kind: Deployment
name: my-app
namespace: production
- requirementName: app-service
apiVersion: v1
kind: Service
name: my-app-service
namespace: production
input:
apiVersion: fn.crossplane.io/v1beta1
kind: ProcessorInput
action: upgrade
```
Functions access these resources through the standard request structure:
```python
from crossplane.function import request, response
def operate(req, rsp):
# Access required resources
deployment = request.get_required_resource(req, "app-deployment")
service = request.get_required_resource(req, "app-service")
if not deployment or not service:
response.set_output(rsp, {"error": "Required resources not found"})
return
# Process the resources
new_replicas = deployment["spec"]["replicas"] * 2
# Return updated resources with full GVK and metadata for server-side apply
rsp.desired.resources["app-deployment"].resource.update({
"apiVersion": "apps/v1",
"kind": "Deployment",
"metadata": {
"name": deployment["metadata"]["name"],
"namespace": deployment["metadata"]["namespace"]
},
"spec": {"replicas": new_replicas}
})
```
## Status and monitoring
Operations provide rich status information:
```yaml
status:
conditions:
- type: Synced
status: "True"
reason: ReconcileSuccess
- type: Succeeded
status: "True"
reason: PipelineSuccess
- type: ValidPipeline
status: "True"
reason: ValidPipeline
failures: 1 # Number of retry attempts
pipeline:
- step: create-backup
output:
backupId: "backup-20240115-103000"
size: "2.3GB"
appliedResourceRefs:
- apiVersion: "v1"
kind: "Secret"
namespace: "production"
name: "backup-secret"
- apiVersion: "apps/v1"
kind: "Deployment"
name: "updated-deployment"
```
**Key status fields:**
- **`conditions`**: Standard Crossplane conditions (Synced) and Operation-specific conditions:
- **`Succeeded`**: `True` when the operation completed successfully, `False` when it failed
- **`ValidPipeline`**: `True` when all functions have the required `operation` capability
- **`failures`**: Number of times the operation has failed and retried
- **`pipeline`**: Output from each function step for tracking progress
- **`appliedResourceRefs`**: References to all resources the Operation created or modified
### Events
Operations emit Kubernetes events for important activities:
- Function run results and warnings
- Resource apply failures
- Operation lifecycle events (creation, completion, failure)
### Troubleshooting operations
**Check operation status:**
```shell
kubectl get operation my-operation -o wide
```
**View detailed information:**
```shell
kubectl describe operation my-operation
```
**Common failure scenarios:**
1. **Operations do nothing** - Operations feature not enabled:
```yaml
# Operation exists but has no status conditions and never progresses
status: {}
```
*Solution*: enable Operations by adding `--enable-operations` to Crossplane's startup arguments.
2. **ValidPipeline condition is False** - Function doesn't support operations:
```yaml
conditions:
- type: ValidPipeline
status: "False"
reason: InvalidFunctionCapability
message: "Function function-name doesn't support operations"
```
*Solution*: use a function that declares `operation` capability.
3. **Succeeded condition is False** - Function run failed:
```yaml
conditions:
- type: Succeeded
status: "False"
reason: PipelineFailure
message: "Function returned error: connection timeout"
```
*Solution*: view function logs and fix the underlying issue.
4. **Resource apply failures** - View events for details:
```shell
kubectl get events --field-selector involvedObject.name=my-operation
```
**Debug function runs:**
```shell
# View function logs
kubectl logs -n crossplane-system deployment/function-python
# Check operation events
kubectl get events --field-selector involvedObject.kind=Operation
# Inspect operation status in detail
kubectl get operation my-operation -o jsonpath='{.status.pipeline}' | jq '.'
```
## Resource management
Operations can create or change any Kubernetes resources using server-side
apply with force ownership. This means:
**What Operations can do:**
- Create new resources of any kind
- Change existing resources by taking ownership of specific fields
- Apply changes that may conflict with other controllers
**What Operations can't do:**
- Delete resources (current limitation of alpha implementation)
- Establish owner references (resources aren't garbage collected)
- Continuously maintain desired state (they run once)
{{<hint "important">}}
Use caution with Operations that change resources managed by other controllers.
Operations force ownership when applying changes, which can cause conflicts.
{{</hint>}}
## Test an operation
You can preview the output of any Operation using the Crossplane CLI. You
don't need a Crossplane control plane to do this. The Crossplane CLI uses Docker
Engine to run functions.
{{<hint "tip">}}
See the [Crossplane CLI docs]({{<ref "../cli">}}) to
learn how to install and use the Crossplane CLI.
{{< /hint >}}
{{<hint "important">}}
Running `crossplane alpha render op` requires [Docker](https://www.docker.com).
{{< /hint >}}
Provide an operation, composition functions, and any required resources to render
the output locally.
```shell
crossplane alpha render op operation.yaml functions.yaml --required-resources=ingress.yaml
```
`crossplane alpha render op` prints the Operation status and any resources the
operation functions created or modified. It shows what would happen if you
applied the Operation to a cluster.
```yaml
---
# Operation status showing function results
apiVersion: ops.crossplane.io/v1alpha1
kind: Operation
metadata:
name: ingress-cert-monitor
status:
conditions:
- type: Succeeded
status: "True"
reason: PipelineSuccess
pipeline:
- step: check-ingress-certificate
output:
certificateExpires: "Sep 29 08:34:02 2025 GMT"
daysUntilExpiry: 53
hostname: google.com
ingressName: example-app
status: ok
---
# Modified Ingress resource with certificate annotations
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
annotations:
cert-monitor.crossplane.io/expires: Sep 29 08:34:02 2025 GMT
cert-monitor.crossplane.io/days-until-expiry: "53"
cert-monitor.crossplane.io/status: ok
name: example-app
namespace: default
spec:
# ... ingress spec unchanged
```
Use `--required-resources` to provide resources that your operation functions
need access to. You can specify multiple files or use glob patterns:
```shell
# Multiple specific files
crossplane alpha render op operation.yaml functions.yaml \
--required-resources=deployment.yaml,service.yaml,configmap.yaml
# Glob pattern for all YAML files in a directory
crossplane alpha render op operation.yaml functions.yaml \
--required-resources="resources/*.yaml"
```
{{<hint "tip">}}
Use the `crossplane alpha render op` command to test your Operations locally
before deploying them to a cluster. The command helps validate function logic
and required resource access patterns.
{{</hint>}}
## Best practices
### Operation-specific practices
1. **Plan for rollback** - Design operations to be reversible when possible,
because Operations don't auto rollback like Compositions
1. **Make operations idempotent** - Operations should be safe to retry if they
fail partway through
1. **Use required resources** - Prepopulate functions with needed resources for
efficiency rather than requesting them during running
### Function development
1. **Declare capabilities** - Explicitly declare `operation` capability in
function metadata to enable Operations support
1. **Return meaningful output** - Use the output field to track what the
operation accomplished for monitoring and debugging
## Next steps
- [Get started with Operations]({{<ref "../get-started/get-started-with-operations">}}) to create your first Operation
- Learn about [CronOperation]({{<ref "cronoperation">}}) for scheduled operations
- Learn about [WatchOperation]({{<ref "watchoperation">}}) for reactive operations