app-migration-execution

# Application migration execution <!-- Disabling markdownlint MD029 to provide explicit ordering to avoid confusing the LLM. --> <!-- markdownlint-disable MD029 --> <!-- Disabling markdownlint MD030 to allow the list overflowing to numbers >=10. --> <!-- markdownlint-disable MD030 --> ## Purpose Orchestrate the GKE deployment sequence for a translated Amazon Elastic Kubernetes Service (EKS) workload, enforcing verification gates, user approval steps, and utilizing local state persistence to enable recovery from execution failures. ## When to use this skill Trigger on: - "Deploy the translated manifests to GKE" - "Execute application migration execution phase" - "Run the deployment sequence on GKE" ## Prerequisites - `python3` version 3.10 or later - Install dependencies listed in `scripts/requirements.txt`: `pip install --require-hashes -r scripts/requirements.txt` - `kubectl` version 1.30 or later - Path to directory containing translated GKE manifests, for example `./translated-manifests/` - Active target GKE cluster context configured in `kubectl` ## Assets and references The following schema files under `assets/schemas/` define the JSON contracts used by this skill: - `workload-handoff.schema.json`: Schema for cluster-level workload handoff specifications. - `workload-handoff-namespace.schema.json`: Schema for namespace-level workload handoff specifications. - `platform-handoff.schema.json`: Schema for platform infrastructure handoffs. - `identity-map.schema.json`: Schema for ServiceAccount identity mappings. - `image-map.schema.json`: Schema for container image repository mappings. - `network-map.schema.json`: Schema for ingress and network policy mappings. - `observability-map.schema.json`: Schema for metrics and observability mappings. - `storage-map.schema.json`: Schema for StorageClass mappings. > [!NOTE] When executing `scripts/execute_migration.py`, the script > automatically scans the handoff directory and validates all present handoff > and mapping JSON specifications against the schemas above using Python > `jsonschema` prior to manifest deployment. ## Procedure ### Step 1 — Verify cluster connectivity Ensure the active `kubectl` context matches the target cluster. ### Step 2 — Run the deployment execution script Execute the orchestrator script to manage the multi-phase deployment sequence: ```bash python3 scripts/execute_migration.py \ --manifests-dir ./translated-manifests \ --namespace production-app \ --auto-approve ``` The script runs the sequence in 5 distinct Phases: - **Phase 1: Namespace and Identity:** Includes `Namespace`, `ServiceAccount`, `CustomResourceDefinition`, and RBAC resources. - **Phase 2: Storage and Data Sync:** Includes `StorageClass`, `PersistentVolumeClaim` (PVC), and `VolumeSnapshot` resources. - Provisions GKE target volumes by applying the translated PVC and StorageClass manifests. - **Approval Gate:** You MUST ask the user if they want to perform active data replication/sync. If approved, guide them through executing the replication using the strategies in [pvc_migration_strategies.md](../storage-translation/references/pvc_migration_strategies.md). If not, proceed to Phase 3 with empty target volumes. - **Phase 3: Workloads Deployment:** Includes `Deployment`, `StatefulSet`, `DaemonSet`, `Job`, and custom workload operator resources. - **Phase 4: Observability Integration:** Includes `PodMonitoring`, `ClusterPodMonitoring`, and `ServiceMonitor` resources. - **Phase 5: Network Exposure:** Includes `Gateway`, `HTTPRoute`, `Service`, `Ingress`, and `NetworkPolicy` resources. > [!NOTE] For any custom CRDs or third-party custom resources that fall outside > standard built-in kinds, evaluate their function and place or organize them > into the appropriate Phase directory or apply them during the relevant phase, > for example CRD definitions in Phase 1, custom workload CRs in Phase 3, or > custom network policies in Phase 5. ### Step 3 — State recovery If the migration script aborts or fails at any Phase: 1. Resolve the underlying error, such as target resource limits, quota, or Identity and Access Management (IAM) configuration issues. 2. Re-run the script with the same parameters. 3. The script will automatically detect `migration-execution-state.json` and prompt you to **Resume** (skip completed phases and verify dependencies) or **Start Fresh**.